View MAX5481_146355.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

19-3708; Rev 3; 4/07
www..com
10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers
General Description
The MAX5481-MAX5484 10-bit (1024-tap) nonvolatile, linear-taper, programmable voltage-dividers and variable resistors perform the function of a mechanical potentiometer, but replace the mechanics with a pinconfigurable 3-wire serial SPITM-compatible interface or up/down digital interface. The MAX5481/MAX5482 are 3-terminal voltage-dividers and the MAX5483/MAX5484 are 2-terminal variable resistors. The MAX5481-MAX5484 feature an internal, nonvolatile, electrically erasable programmable read-only memory (EEPROM) that stores the wiper position for initialization during power-up. The 3-wire SPI-compatible serial interface allows communication at data rates up to 7MHz. A pin-selectable up/down digital interface is also available. The MAX5481-MAX5484 are ideal for applications requiring digitally controlled potentiometers. Two end-toend resistance values are available (10k and 50k) in a voltage-divider or a variable-resistor configuration (see the Selector Guide). The nominal resistor temperature coefficient is 35ppm/C end-to-end, and only 5ppm/C ratiometric, making these devices ideal for applications requiring low-temperature-coefficient voltage-dividers, such as low-drift, programmable gain-amplifiers. The MAX5481-MAX5484 operate with either a +2.7V to +5.25V single power supply or 2.5V dual power supplies. These devices consume 400A (max) of supply current when writing data to the nonvolatile memory and 1.0A (max) of standby supply current. The MAX5481-MAX5484 are available in a space-saving (3mm x 3mm), 16-pin TQFN, or a 14-pin TSSOP package and are specified over the extended (-40C to +85C) temperature range.
Features
1024 Tap Positions Power-On Recall of Wiper Position from Nonvolatile Memory 16-Pin (3mm x 3mm x 0.8mm) TQFN or 14-Pin TSSOP Package 35ppm/C End-to-End Resistance Temperature Coefficient 5ppm/C Ratiometric Temperature Coefficient 10k and 50k End-to-End Resistor Values Pin-Selectable SPI-Compatible Serial Interface or Up/Down Digital Interface 1A (max) Standby Current Single +2.7V to +5.25V Supply Operation Dual 2.5V Supply Operation
MAX5481-MAX5484
Pin Configurations
DIN(U/D) 10 TOP VIEW CS SCLK(INC) SPI/UD 9 8 7 VSS N.C. N.C. N.C.
12
GND
11
13 14 15 16 1 H
INTERFACE
VDD N.C.
VSS
MAX5481* MAX5482*
6 5
2 W
3 L DIN(U/D) 10
4 N.C. SPI/UD 9 8 7 VSS N.C. N.C. N.C.
TQFN
*SEE FUNCTIONAL DIAGRAM
Gain and Offset Adjustment LCD Contrast Adjustment Pressure Sensors
Low-Drift Programmable Gain Amplifiers Mechanical Potentiometer Replacement
GND
12 13 14 15 16 1 D.N.C.
11
INTERFACE
VDD
SCLK(INC)
Applications
CS
Ordering Information
PART MAX5481ETE MAX5481EUD PIN-PACKAGE 16 TQFN-EP* 14 TSSOP PKG CODE T1633F-3 U14-1 TOP MARK ACP --
N.C.
VSS
MAX5483 MAX5484
6 5
2 W
3 L
4 N.C.
TQFN
Note: All devices are specified over the -40C to +85C operating temperature range. *EP = Exposed pad. Ordering Information continued at end of data sheet.
Pin Configurations continued at end of data sheet. Selector Guide appears at end of data sheet. SPI is a trademark of Motorola, Inc. 1
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim's website at www.maxim-ic.com.
www..com
10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers MAX5481-MAX5484
ABSOLUTE MAXIMUM RATINGS
VDD to GND ...........................................................-0.3V to +6.0V VSS to GND............................................................-3.5V to +0.3V VDD to VSS .............................................................-0.3V to +6.0V H, L, W to VSS ..................................(VSS - 0.3V) to (VDD + 0.3V) CS, SCLK(INC), DIN(U/D), SPI/UD to GND ..-0.3V to (VDD + 0.3V) Maximum Continuous Current into H, L, and W MAX5481/MAX5483.........................................................5mA MAX5482/MAX5484......................................................1.0mA Maximum Current into Any Other Pin ...............................50mA Continuous Power Dissipation (TA = +70C) 16-Pin TQFN (derate 17.5mW/C above +70C) .....1398.6mW 14-Pin TSSOP (derate 9.1mW/C above +70C) ..........727mW Operating Temperature Range ...........................-40C to +85C Junction Temperature ......................................................+150C Storage Temperature Range .............................-60C to +150C Lead Temperature (soldering, 10s) .................................+300C
Stresses beyond those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(VDD = +2.7V to +5.25V, VSS = GND = 0, VH = VDD, VL = 0, TA = -40C to +85C, unless otherwise noted. Typical values are at VDD = +5.0V, TA = +25C, unless otherwise noted.) (Note 1)
PARAMETER SYMBOL CONDITIONS MIN 10 2 2 1 1 35 5 FSE ZSE RH-L CW MAX5481 MAX5482 MAX5481 MAX5482 MAX5481 MAX5482 MAX5481 MAX5482 -4 -4 0 0 7.5 37.5 -2.5 -0.75 +3.3 +1.45 10 50 60 6.3 k 25 0 0 +5 +5 12.5 62.5 TYP MAX UNITS Bits LSB LSB ppm/C ppm/C LSB LSB k pF DC PERFORMANCE (MAX5481/MAX5482 programmable voltage-divider) Resolution N VDD = 2.7V Integral Nonlinearity (Note 2) INL VDD = 5V VDD = 2.7V Differential Nonlinearity (Note 2) DNL VDD = 5V End-to-End Resistance Temperature Coefficient Ratiometric Resistance Temperature Coefficient Full-Scale Error Zero-Scale Error End-to-End Resistance Wiper Capacitance TCR
W at code = 15, H and L shorted to VSS, measure Resistance from W to L and H resistance from W to H, Figures 1 and 2 DC PERFORMANCE (MAX5483/MAX5484 variable resistor) Resolution N VDD = 2.7V Integral Nonlinearity (Note 3) INL_R VDD = 3V VDD = 5V VDD = 2.7V Differential Nonlinearity (Note 3) DNL_R VDD = 3V VDD = 5V Variable-Resistor Temperature Coefficient TCVR
10 -4 -4 -1 -1 -1.6 -1.4 -1.3 +0.45 +0.4 +0.35 35 +4 +4 +1 +1
Bits LSB
LSB
VDD = 3V to 5.25V; code = 128 to 1024
ppm/C
2
_______________________________________________________________________________________
www..com
10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers
ELECTRICAL CHARACTERISTICS (continued)
(VDD = +2.7V to +5.25V, VSS = GND = 0, VH = VDD, VL = 0, TA = -40C to +85C, unless otherwise noted. Typical values are at VDD = +5.0V, TA = +25C, unless otherwise noted.) (Note 1)
PARAMETER Full-Scale Wiper-to-End Resistance Zero-Scale Resistor Error Wiper Resistance Wiper Capacitance SYMBOL RW-L RZ RW CW MAX5483 MAX5484 Code = 0 VDD 3V (Note 4) MAX5483 MAX5484 CONDITIONS MIN 7.5 37.5 TYP 10 50 70 110 50 60 MAX 12.5 62.5 UNITS k k pF
MAX5481-MAX5484
DIGITAL INPUTS (CS, SCLK(INC), DIN(U/D), SPI/UD) (Note 5) VDD = +3.6V to +5.25V VDD = +2.7V to +3.6V VDD = +2.5V, VSS = -2.5V VDD = +2.7V to +5.25V VDD = +2.5V, VSS = -2.5V 5 Wiper at code = 01111 01111, CLW = 10pF VDD = 3V, wiper at code = 01111 01111, 1VRMS at 10kHz is applied at H, 10pF load on W TA = +85C TA = +25C TA = +85C VDD VDD VSS IPG VSS = GND = 0 GND = 0 VDD - VSS 5.25V During nonvolatile write; digital inputs = VDD or GND During nonvolatile write only; digital inputs = VDD or GND IDD Digital inputs = VDD or GND, TA = +25C 2.70 2.50 -2.5 220 4 0.6 1 MAX5481 MAX5482 MAX5481 MAX5482 250 50 0.026 % 0.03 2.4 0.7 x VDD 2.0 0.8 V 0.6 1 A pF V
Single-supply operation Input-High Voltage VIH Dual-supply operation Single-supply operation Input-Low Voltage VIL Dual-supply operation Input Leakage Current Input Capacitance DYNAMIC CHARACTERISTICS Wiper -3dB Bandwidth IIN CIN
kHz
Total Harmonic Distortion
THD
NONVOLATILE MEMORY RELIABILITY Data Retention Endurance POWER SUPPLY Single-Supply Voltage Dual-Supply Voltage Average Programming Current Peak Programming Current Standby Current 5.25 5.25 -0.2 400 V V A mA A 50 200,000 50,000 Years Stores
_______________________________________________________________________________________
3
www..com
10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers MAX5481-MAX5484
TIMING CHARACTERISTICS
(VDD = +2.7V to +5.25V, VSS = GND = 0, VH = VDD, VL = 0, TA = -40C to +85C, unless otherwise noted. Typical values are at VDD = +5.0V, TA = +25C, unless otherwise noted.) (Note 1)
PARAMETER ANALOG SECTION Wiper Settling Time (Note 6) tS MAX5481 MAX5482 5 22 7 140 60 60 60 0 40 0 15 60 150 12 25 20 25 25 25 50 50 50 50 12 s SYMBOL CONDITIONS MIN TYP MAX UNITS
SPI-COMPATIBLE SERIAL INTERFACE (Figure 3) SCLK Frequency SCLK Clock Period SCLK Pulse-Width High SCLK Pulse-Width Low CS Fall to SCLK Rise Setup SCLK Rise to CS Rise Hold DIN to SCLK Setup DIN Hold after SCLK SCLK Rise to CS Fall Delay CS Rise to SCLK Rise Hold CS Pulse-Width High Write NV Register Busy Time CS to INC Setup INC High to U/D Change U/D to INC Setup INC Low Period INC High Period INC Inactive to CS Inactive CS Deselect Time (Store) INC Cycle Time INC Active to CS Inactive Wiper Store Cycle fSCLK tCP tCH tCL tCSS tCSH tDS tDH tCS0 tCS1 tCSW tBUSY tCI tID tDI tIL tIH tIC tCPH tCYC tIK tWSC MHz ns ns ns ns ns ns ns ns ns ns ms ns ns ns ns ns ns ns ns ns ms
UP/DOWN DIGITAL INTERFACE (Figure 8)
Note 1: 100% production tested at TA = +25C and TA = +85C. Guaranteed by design to TA = -40C. Note 2: The DNL and INL are measured with the device configured as a voltage-divider with H = VDD and L = VSS. The wiper terminal (W) is unloaded and measured with a high-input-impedance voltmeter. Note 3: The DNL_R and INL_R are measured with D.N.C. unconnected and L = VSS = 0. For VDD = 5V, the wiper terminal is driven with a source current of IW = 80A for the 50k device and 400A for the 10k device. For VDD = 3V, the wiper terminal is driven with a source current of 40A for the 50k device and 200A for the 10k device. Note 4: The wiper resistance is measured using the source currents given in Note 3. Note 5: The device draws higher supply current when the digital inputs are driven with voltages between (VDD - 0.5V) and (GND + 0.5V). See Supply Current vs. Digital Input Voltage in the Typical Operating Characteristics. Note 6: Wiper settling test condition uses the voltage-divider configuration with a 10pF load on W. Transition code from 00000 00000 to 01111 01111 and measure the time from CS going high to the wiper voltage settling to within 0.5% of its final value.
4
_______________________________________________________________________________________
www..com
10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers MAX5481-MAX5484
Typical Operating Characteristics
(VDD = 5.0V, VSS = 0, TA = +25C, unless otherwise noted.)
DNL vs. CODE (MAX5483)
MAX5481 toc01
DNL vs. CODE (MAX5483)
MAX5481 toc02
INL vs. CODE (MAX5483)
1.5 1.0 INL (LSB) 0.5 0 -0.5 -1.0 -1.5 -2.0 VDD = 2.7V
MAX5481 toc03 MAX5481 toc09 MAX5481 toc06
1.0 0.8 0.6 0.4 DNL (LSB) VDD = 2.7V
1.0 0.8 0.6 0.4 DNL (LSB) 0.2 0 -0.2 -0.4 -0.6 -0.8 -1.0 VDD = 5V
2.0
0.2 0 -0.2 -0.4 -0.6 -0.8 -1.0 0 128 256 384 512 640 768 896 1024 CODE
0
128 256 384 512 640 768 896 1024 CODE
0
128 256 384 512 640 768 896 1024 CODE
INL vs. CODE (MAX5483)
MAX5481 toc04
INL vs. CODE (MAX5483)
MAX5481 toc05
DNL vs. CODE (MAX5481)
1.0 0.8 0.6 0.4 DNL (LSB) VDD = 2.7V
2.0 1.5 1.0 INL (LSB) VDD = 3V
2.0 1.5 1.0 INL (LSB) 0.5 0 -0.5 -1.0 -1.5 -2.0 VDD = 5V
0.5 0 -0.5 -1.0 -1.5 -2.0 0 128 256 384 512 640 768 896 1024 CODE
0.2 0 -0.2 -0.4 -0.6 -0.8 -1.0
0
128 256 384 512 640 768 896 1024 CODE
0
128 256 384 512 640 768 896 1024 CODE
DNL vs. CODE (MAX5481)
MAX5481 toc07
INL vs. CODE (MAX5481)
0.8 0.6 0.4 INL (LSB) INL (LSB) 0.2 0 -0.2 -0.4 -0.6 -0.8 -1.0 VDD = 2.7V
MAX5481 toc08
INL vs. CODE (MAX5481)
1.0 0.8 0.6 0.4 0.2 0 -0.2 -0.4 -0.6 -0.8 -1.0 VDD = 5V
1.0 0.8 0.6 0.4 DNL (LSB) 0.2 0 -0.2 -0.4 -0.6 -0.8 -1.0 0 VDD = 5V
1.0
128 256 384 512 640 768 896 1024 CODE
0
128 256 384 512 640 768 896 1024 CODE
0
128 256 384 512 640 768 896 1024 CODE
_______________________________________________________________________________________
5
www..com
10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers MAX5481-MAX5484
Typical Operating Characteristics (continued)
(VDD = 5.0V, VSS = 0, TA = +25C, unless otherwise noted.)
DNL vs. CODE (MAX5484)
MAX5481 toc10
DNL vs. CODE (MAX5484)
MAX5481 toc11
INL vs. CODE (MAX5484)
0.8 0.6 0.4 INL (LSB) 0.2 0 -0.2 -0.4 -0.6 -0.8 -1.0 VDD = 2.7V
MAX5481 toc12 MAX5481 toc18 MAX5481 toc15
1.0 0.8 0.6 0.4 DNL (LSB) VDD = 2.7V
1.0 0.8 0.6 0.4 DNL (LSB) 0.2 0 -0.2 -0.4 -0.6 -0.8 -1.0 VDD = 5V
1.0
0.2 0 -0.2 -0.4 -0.6 -0.8 -1.0 0 128 256 384 512 640 768 896 1024 CODE
0
128 256 384 512 640 768 896 1024 CODE
0
128 256 384 512 640 768 896 1024 CODE
INL vs. CODE (MAX5484)
MAX5481 toc13
DNL vs. CODE (MAX5482)
0.8 0.6 0.4 DNL (LSB) DNL (LSB) 0.2 0 -0.2 -0.4 -0.6 -0.8 -1.0 VDD = 2.7V
MAX5481 toc14
DNL vs. CODE (MAX5482)
1.0 0.8 0.6 0.4 0.2 0 -0.2 -0.4 -0.6 -0.8 -1.0 VDD = 5V
1.0 0.8 0.6 0.4 INL (LSB) 0.2 0 -0.2 -0.4 -0.6 -0.8 -1.0 0 VDD = 5V
1.0
128 256 384 512 640 768 896 1024 CODE
0
128 256 384 512 640 768 896 1024 CODE
0
128 256 384 512 640 768 896 1024 CODE
INL vs. CODE (MAX5482)
MAX5481 toc16
INL vs. CODE (MAX5482)
0.8 0.6 0.4 INL (LSB) 0.2 0 -0.2 -0.4 -0.6 -0.8 -1.0 20 10 0 128 256 384 512 640 768 896 1024 CODE 0 0 RW () VDD = 5V
MAX5481 toc17
1.0 0.8 0.6 0.4 INL (LSB) 0.2 0 -0.2 -0.4 -0.6 -0.8 -1.0 0 VDD = 2.7V
1.0
WIPER RESISTANCE vs. CODE (VARIABLE RESISTOR, TA = -40C)
80 70 60 50 40 30
128 256 384 512 640 768 896 1024 CODE
128 256 384 512 640 768 896 1024 CODE
6
_______________________________________________________________________________________
www..com
10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers MAX5481-MAX5484
Typical Operating Characteristics (continued)
(VDD = 5.0V, VSS = 0, TA = +25C, unless otherwise noted.)
WIPER RESISTANCE vs. CODE (VARIABLE RESISTOR, TA = +25C)
MAX5481 toc19
WIPER RESISTANCE vs. CODE (VARIABLE RESISTOR, TA = +85C)
MAX5481 toc20
W-TO-L RESISTANCE vs. CODE (MAX5484)
MAX5481 toc21
80 70 60 50 RW () 40 30 20 10 0 0
80 70 60
70 60 50 RWL (k) 40 30 20 10 0
50 RW () 128 256 384 512 640 768 896 1024 CODE 40 30 20 10 0 0 128 256 384 512 640 768 896 1024 CODE
0
128 256 384 512 640 768 896 1024 CODE
W-TO-L RESISTANCE vs. CODE (MAX5483)
MAX5481 toc22
WIPER RESISTANCE vs. WIPER VOLTAGE (VARIABLE RESISTOR)
MAX5481 toc23
END-TO-END (RHL) % CHANGE vs. TEMPERATURE (VOLTAGE-DIVIDER)
END-TO-END RESISTANCE CHANGE (%) 1.5 1.0 0.5 0 -0.5 -1.0 -1.5 -2.0 -40 -15 10 35 60 85
MAX5481 toc24
14 12 10 RWL (k)
22.0 21.5 21.0 20.5 RW () 20.0 19.5 VDD = 5V CODE = 00 0000
2.0
8 6 4 2 0 0 128 256 384 512 640 768 896 1024 CODE
19.0 18.5 18.0 0 1 2 3 4 5 WIPER VOLTAGE (V)
TEMPERATURE (C)
WIPER-TO-END RESISTANCE (RWL) % CHANGE vs. TEMPERATURE (VARIABLE RESISTOR)
MAX5481 toc25
STANDBY SUPPLY CURRENT vs. TEMPERATURE
VDD = 5.25V 1.2
MAX5481 toc26
DIGITAL SUPPLY CURRENT vs. DIGITAL INPUT VOLTAGE
VDD = 5V 1000
MAX5481 toc27
2.0 WIPER-TO-END RESISTANCE CHANGE (%) CODE = 11 1111 1111 1.5 1.0
1.5
10,000
0 -0.5 -1.0 -1.5 -2.0 -40 -15 10 35 60 85 TEMPERATURE (C)
IDD (A)
IDD (A)
0.5
0.9
100
0.6
10
0.3
1
0 -40 -15 10 35 60 85 TEMPERATURE (C)
0.1 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 DIGITAL INPUT VOLTAGE (V)
_______________________________________________________________________________________
7
www..com
10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers MAX5481-MAX5484
Typical Operating Characteristics (continued)
(Circuit of Figure 1, TA = +25C, unless otherwise noted.)
TAP-TO-TAP SWITCHING TRANSIENT RESPONSE (MAX5481)
MAX5481 toc28
TAP-TO-TAP SWITCHING TRANSIENT RESPONSE (MAX5482)
MAX5481 toc29
CS 2V/div
CS 2V/div
VW (AC-COUPLED) 20mV/div H = VDD, L = GND CW = 10pF FROM CODE 01 1111 1111 TO CODE 10 0000 0000 1s/div H = VDD, L = GND CW = 10pF FROM CODE 01 1111 1111 TO CODE 10 0000 0000 4s/div
VW (AC-COUPLED) 20mV/div
WIPER RESPONSE vs. FREQUENCY (MAX5481)
MAX5481 toc30
WIPER RESPONSE vs. FREQUENCY (MAX5482)
MAX5481 toc31
THD+N vs. FREQUENCY (MAX5481)
CODE 01111 01111 CW = 10pF 1
MAX5481 toc32
0 CW = 10pF
0
10
-5
-5
CW = 10pF
GAIN (dB)
-10 CW = 30pF -15
CW = 30pF -15
THD+N (%) 1000
GAIN (dB)
-10
0.1
0.01
-20 CODE = 01111 01111 -25 0.1 1 10 FREQUENCY (kHz) 100 1000
-20 CODE = 01111 01111 -25 0.1 1 10 FREQUENCY (kHz) 100
0.001
0.0001 0.01 0.1 1 FREQUENCY (kHz) 10 100
THD+N vs. FREQUENCY (MAX5482)
MAX5481 toc33
RATIOMETRIC TEMPERATURE COEFFICIENT vs. CODE
MAX5481 toc34
VARIABLE-RESISTOR TEMPERATURE COEFFICIENT vs. CODE
VDD = +3V TA = -40C TO +85C
MAX5481 toc35
10 CODE 01111 01111 CW = 10pF 1
200 180 RATIOMETRIC TEMPCO (ppm) 160 140 120 100 80 60 40 20 50k 10k VOLTAGE-DIVIDER VDD = +3V TA = -40C TO +85C
700 600 500 TCVR (ppm) 400 300 200 50k 100 0 10k
THD+N (%)
0.1
0.01
0.001
0.0001 0.01 0.1 1 FREQUENCY (kHz) 10 100
0 0 128 256 384 512 640 768 896 1024 CODE
0
128 256 384 512 640 768 896 1024 CODE
8
_______________________________________________________________________________________
www..com
10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers
Pin Description
(MAX5481/MAX5482 Voltage-Dividers)
PIN TQFN 1 2 3 4-7, 15 8, 16 TSSOP 12 11 10 7, 8, 9, 13 14 NAME H W L N.C. VSS High Terminal Wiper Terminal Low Terminal No Connection. Not internally connected. Negative Power-Supply Input. For single-supply operation, connect VSS to GND. For dualsupply operation, -2.5V VSS -0.2V as long as (VDD - VSS) +5.25V. Bypass VSS to GND with a 0.1F ceramic capacitor as close to the device as possible. Interface-Mode Select. Select serial SPI interface when SPI/UD = 1. Select serial up/down interface when SPI/UD = 0. Serial SPI Interface Data Input (SPI/UD = 1) 10 5 DIN(U/D) Up/Down Control Input (SPI/UD = 0). With DIN(U/D) low, a high-to-low SCLK(INC) transition decrements the wiper position. With DIN(U/D) high, a high-to-low SCLK(INC) transition increments the wiper position. Serial SPI Interface Clock Input (SPI/UD = 1) 11 12 13 14 EP 4 3 2 1 -- SCLK(INC) CS GND VDD EP Wiper-Increment Control Input (SPI/UD = 0). With CS low, the wiper position moves in the direction determined by the state of DIN(U/D) on a high-to-low transition. Active-Low Digital Input Chip Select Ground Positive Power-Supply Input (+2.7V VDD +5.25V). Bypass VDD to GND with a 0.1F ceramic capacitor as close to the device as possible. Exposed Pad. Externally connect EP to VSS or leave unconnected. FUNCTION
MAX5481-MAX5484
9
6
SPI/UD
_______________________________________________________________________________________
9
www..com
10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers MAX5481-MAX5484
Pin Description (continued)
(MAX5483/MAX5484 Variable Resistors)
PIN TQFN 4-7, 15 1 2 3 8, 16 TSSOP 7, 8, 9, 13 12 11 10 14 N.C. D.N.C. W L VSS No Connection. Not internally connected. Do Not Connect. Leave unconnected for proper operation. Wiper Terminal Low Terminal Negative Power-Supply Input. For single-supply operation, connect VSS to GND. For dualsupply operation, -2.5V VSS -0.2V as long as (VDD - VSS) 5.25V. Bypass VSS to GND with a 0.1F ceramic capacitor as close to the device as possible. Interface-Mode Select. Select serial SPI interface when SPI/UD = 1. Select serial up/down interface when SPI/UD = 0. Serial SPI Interface Data Input (SPI/UD = 1) 10 5 DIN(U/D) Up/Down Control Input (SPI/UD = 0). With DIN(U/D) low, a high-to-low SCLK(INC) transition decrements the wiper position. With DIN(U/D) high, a high-to-low SCLK(INC) transition increments the wiper position. Serial SPI Interface Clock Input (SPI/UD = 1) 11 12 13 14 EP 4 3 2 1 -- SCLK(INC) CS GND VDD EP Wiper Increment Control Input (SPI/UD = 0). With CS low, the wiper position moves in the direction determined by the state of DIN(U/D) on a high-to-low transition. Active-Low Digital Input Chip Select Ground Positive Power-Supply Input (+2.7V VDD +5.25V). Bypass VDD to GND with a 0.1F ceramic capacitor as close to the device as possible. Exposed Pad. Externally connect EP to VSS or leave unconnected. NAME FUNCTION
9
6
SPI/UD
10
______________________________________________________________________________________
www..com
10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers
Functional Diagrams
MAX5481-MAX5484
VDD GND VSS 10-BIT NV MEMORY 10-BIT LATCH 10 DECODER 10
H
W
CS POR SCLK(INC) DIN(U/D) SPI INTERFACE L
MUX
UP/DOWN INTERFACE
SPI/UD
MAX5481 MAX5482
NOTE: THE MAX5481/MAX5482 ARE NOT INTENDED FOR CURRENT TO FLOW THROUGH THE WIPER (SEE THE MAX5481/MAX5482 PROGRAMMABLE VOLTAGE-DIVIDER SECTION).
______________________________________________________________________________________
11
www..com
10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers MAX5481-MAX5484
Functional Diagrams (continued)
VDD GND VSS 10-BIT NV MEMORY 10-BIT LATCH 10 DECODER 10 H
L
CS POR SCLK(INC) DIN(U/D) SPI INTERFACE
MUX
UP/DOWN INTERFACE
SPI/UD
MAX5483 MAX5484
Detailed Description
The MAX5481/MAX5482 linear programmable voltagedividers and the MAX5483/MAX5484 variable resistors feature 1024 tap points (10-bit resolution) (see the Functional Diagrams). These devices consist of multiple strings of equal resistor segments with a wiper contact that moves among the 1024 points through a pin-selectable 3-wire SPI-compatible serial interface or up/down interface. The MAX5481/MAX5483 provide a total end-to-end resistance of 10k, and the MAX5482/MAX5484 have an end-to-end resistance of 50k. The MAX5481/MAX5482 allow access to the high, low, and wiper terminals for a standard voltagedivider configuration.
MAX5481/MAX5482 Programmable Voltage-Dividers
The MAX5481/MAX5482 programmable voltagedividers provide a weighted average of the voltage between the H and L inputs at the W output. Both devices feature 10-bit resolution and provide up to 1024 tap points between the H and L voltages. Ideally, the VL voltage occurs at the wiper terminal (W) when all data bits are zero and the VH voltage occurs at the wiper terminal when all data bits are one. The step size (1 LSB) voltage is equal to the voltage applied across terminals H and L divided by 210. Calculate the wiper voltage VW as follows: V V + ZSE V HL - FSE + V + VW (D) = D VZSE L 1023
(
)
12
______________________________________________________________________________________
www..com
10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers MAX5481-MAX5484
18 16 14 12 RW-H (k) RW-L (k) 10 8 6 4 2 0 0 128 256 384 512 640 768 896 1024 CODE (DECIMAL) 50k DEVICE SCALES BY A FACTOR OF FIVE 18 16 14 12 10 8 6 4 2 0 0 128 256 384 512 640 768 896 1024 CODE (DECIMAL) 50k DEVICE SCALES BY A FACTOR OF FIVE
Figure 1. Resistance from W to H vs. Code (10k Voltage-Divider)
Figure 2. Resistance from W to L vs. Code (10k Voltage-Divider)
where D is the decimal equivalent of the 10 data bits written (0 to 1023), VHL is the voltage difference between the H and L terminals: V VFSE = FSE HL ,and 1024 V VZSE = ZSE HL 1024 The MAX5481 includes a total end-to-end resistance value of 10k while the MAX5482 features an end-toend resistance value of 50k. These devices are not intended to be used as a variable resistor. Wiper current creates a nonlinear voltage drop in series with the wiper. To ensure temperature drift remains within specifications, do not pull current through the voltage-divider wiper. Connect the wiper to a high-impedance node. Figures 1 and 2 show the behavior of the MAX5481's resistance from W to H and from W to L. This does not apply to the variable-resistor devices
Table 1. RWL at Selected Codes
CODE (DECIMAL) 0 1 512 1023 MAX5483 (10k DEVICE) RWL () 70 80 5070 10,070 MAX5484 (50k DEVICE) RWL () 110 160 25,110 50,110
The 10-bit data in the 10-bit latch register selects a wiper position from the 1024 possible positions, resulting in 1024 values for the resistance from W to L. Calculate the resistance from W to L (RWL) by using the following formula: RWL (D) = D x RW-L + RZ 1023
MAX5483/MAX5484 Variable Resistors
The MAX5483/MAX5484 provide a programmable resistance between W and L. The MAX5483 features a total end-to-end resistance value of 10k, while the MAX5484 provides an end-to-end resistance value of 50k. The programmable resolution of this resistance is equal to the nominal end-to-end resistance divided by 1024 (10-bit resolution). For example, each nominal segment resistance is 9.8 and 48.8 for the MAX5483 and the MAX5484, respectively.
where D is decimal equivalent of the 10 data bits written, RW-L is the nominal end-to-end resistance, and RZ is the zero-scale error. Table 1 shows the values of RWL at selected codes for the MAX5483/MAX5484.
Digital Interface
Configure the MAX5481-MAX5484 by a pin-selectable, 3-wire, SPI-compatible serial data interface or an up/down interface. Drive SPI/UD high to select the 3wire SPI-compatible interface. Pull SPI/UD low to select the up/down interface.
______________________________________________________________________________________
13
www..com
10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers MAX5481-MAX5484
Table 2. Command Decoding*
CLOCK EDGE Bit Name Write Wiper Register Copy Wiper Register to NV Register Copy NV Register to Wiper Register 1 -- 0 0 0 2 -- 0 0 0 3 C1 0 1 1 4 C0 0 0 1 5 -- 0 0 0 6 -- 0 0 0 7 -- 0 0 0 8 -- 0 0 0 9 D9 D9 -- -- 10 D8 D8 -- -- 11 D7 D7 -- -- 12 D6 D6 -- -- 13 D5 D5 -- -- 14 D4 D4 -- -- 15 D3 D3 -- -- 16 D2 D2 -- -- 17 D1 D1 -- -- 18 D0 D0 -- -- 19 -- X -- -- ... ... ... ... ... 24 -- X -- --
*D9 is the MSB and D0 is the LSB. X = Don't care.
CS tCSS tCSO SCLK(INC) tCL tCH tCP tCSH
tCSW tCS1
tDS DIN(U/D)
tDH
Figure 3. SPI-Compatible Serial-Interface Timing Diagram (SPI/UD = 1)
SPI-Compatible Serial Interface
Drive SPI/UD high to enable the 3-wire SPI-compatible serial interface (see Figure 3). This write-only interface contains three inputs: chip select (CS), data in (DIN(U/D)), and data clock (SCLK(INC)). Drive CS low to load the data at DIN(U/D) synchronously into the shift register on each SCLK(INC) rising edge. The WRITE command (C1, C0 = 00) requires 24 clock cycles to transfer the command and data (Figure 4a). The COPY commands (C1, C0 = 10 or 11) use either eight clock cycles to transfer the command bits (Figure 4b) or 24 clock cycles with the last 16 data bits disregarded by the device. After loading the data into the shift register, drive CS high to latch the data into the appropriate control register. Keep CS low during the entire serial data stream to avoid corruption of the data. Table 2 shows the command decoding.
Write Wiper Register Data written to this register (C1, C0 = 00) controls the wiper position. The 10 data bits (D9-D0) indicate the position of the wiper. For example, if DIN(U/D) = 00 0000 0000, the wiper moves to the position closest to L. If DIN(U/D) = 11 1111 1111, the wiper moves closest to H. This command writes data to the volatile random access memory (RAM), leaving the NV register unchanged. When the device powers up, the data stored in the NV register transfers to the wiper register, moving the wiper to the stored position. Figure 5 shows how to write data to the wiper register.
14
______________________________________________________________________________________
www..com
10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers MAX5481-MAX5484
a) 24-BIT COMMAND/DATA WORD CS
SCLK(INC) 1 DIN(U/D) 2 3 4 5 6 7 8 9 D9 10 D8 11 D7 12 D6 13 D5 14 D4 15 D3 16 D2 17 D1 18 D0 19 20 21 22 23 24
C1 C0
b) 8-BIT COMMAND WORD CS
SCLK(INC) 1 DIN(U/D) 2 3 4 5 6 7 8
C1 C0
Figure 4. Serial SPI-Compatible Interface Format
CS
1 SCLK(INC)
2
3
4
5
6
7
8
9
10
11 12 13 14
15
16
17
18
19 20 21 22
23
24
C1 C0 DIN(U/D) 0 0 0 0 0 0 0 0 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 X X X X X X
ACTION
WIPER REGISTER UPDATED
Figure 5. Write Wiper Register Operation
______________________________________________________________________________________
15
www..com
10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers MAX5481-MAX5484
Table 3. Truth Table
CS L L L H DIN(U/D) L H X X X X X SCLK(INC) X X L H W Decrement Increment No Change No Change No Change Position Not Stored Position Stored
DIN(U/D) SCLK(INC) C1 0 0 1 C0 0 0 0 0 0 1 2 3 4 5 6 7 8 CS
tBUSY WRITE NV REGISTER (DEVICE IS BUSY)
= High-to-low transition. = Low-to-high transition. X = Don't care.
ACTION
Copy Wiper Register to NV Register The copy wiper register to NV register command (C1, C0 = 10) stores the current position of the wiper to the NV register for use at power-up. Figure 6 shows how to copy data from wiper register to NV register. The operation takes up to 12ms (max) after CS goes high to complete and no other operation should be performed until completion. Copy NV Register to Wiper Register The copy NV register to wiper register (C1, C0 = 11) restores the wiper position to the current value stored in the NV register. Figure 7 shows how to copy data from the NV register to the wiper register.
Figure 6. Copy Wiper Register to NV Register Operation
CS
1 SCLK(INC)
2
3
4
5
6
7
8
C1 DIN(U/D) 0 0 1
C0 1 0 0 0 0
Digital Up/Down Interface
Figure 8 illustrates an up/down serial-interface timing diagram. In digital up/down interface mode (SPI/UD = 0), the logic inputs CS, DIN(U/D), and SCLK(INC) control the wiper position and store it in nonvolatile memory (see Table 3). The chip-select (CS) input enables the serial interface when low and disables the interface when high. The position of the wiper is stored in the nonvolatile register when CS transitions from low to high while SCLK(INC) is high. When the serial interface is active (CS low), a high-tolow (falling edge) transition on SCLK(INC) increments or decrements the internal 10-bit counter depending on the state of DIN(U/D). If DIN(U/D) is high, the wiper increments. If DIN(U/D) is low, the wiper decrements. The device stores the value of the wiper position in the nonvolatile memory when CS transitions from low to high while SCLK(INC) is high. The host system can disable
WIPER REGISTER UPDATED
ACTION
Figure 7. Copy NV Register to Wiper Register Operation
the serial interface and deselect the device without storing the latest wiper position in the nonvolatile memory by keeping SCLK(INC) low while taking CS high. Upon power-up, the MAX5481-MAX5484 load the value of nonvolatile memory into the wiper register, and set the wiper position to the value last stored.
16
______________________________________________________________________________________
www..com
10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers
Standby Mode
The MAX5481-MAX5484 feature a low-power standby mode. When the device is not being programmed, it enters into standby mode and supply current drops to 0.5A (typ).
Applications Information
The MAX5481-MAX5484 are ideal for circuits requiring digitally controlled adjustable resistance, such as LCD contrast control (where voltage biasing adjusts the display contrast), or programmable filters with adjustable gain and/or cutoff frequency. Figures 9 and 10 show an application where a voltagedivider or a variable resistor is used to make an adjustable, positive LCD-bias voltage. The op amp provides buffering and gain to the voltage-divider network made by the programmable voltage-divider (Figure 9) or to a fixed resistor and a variable resistor (see Figure 10).
MAX5481-MAX5484
Nonvolatile Memory
The internal EEPROM consists of a nonvolatile register that retains the last value stored prior to power-down. The nonvolatile register is programmed to midscale at the factory. The nonvolatile memory is guaranteed for 50 years of wiper data retention and up to 200,000 wiper write cycles.
Positive LCD Bias Control
Power-Up
Upon power-up, the MAX5481-MAX5484 load the data stored in the nonvolatile wiper register into the volatile wiper register, updating the wiper position with the data stored in the nonvolatile wiper register.
Programmable Gain and Offset Adjustment
Figure 11 shows an application where a voltage-divider and a variable resistor are used to make a programmable gain and offset adjustment.
WIPER POSITION STORED CS
WIPER POSITION NOT STORED
tCI tIL SCLK(INC)
tCYC tIH
tIC
tCPH
tIK
tID
tDI
tWSC
DIN(U/D) tS
VW NOTES: VW IS NOT A DIGITAL SIGNAL. IT REPRESENTS A WIPER TRANSITION. SCLK(INC) MUST BE AT LOGIC HIGH WHEN DIN(U/D) CHANGES STATE.
Figure 8. Up/Down Serial-Interface Timing Diagram (SPI/UD = 0)
______________________________________________________________________________________
17
www..com
10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers MAX5481-MAX5484
5V H 30V MAX5481 MAX5482 L W MAX480 MAX5481 MAX5482 VOUT L W VOUT VREF H
MAX5483 MAX5484 L
W VIN
Figure 9. Positive LCD Bias Control Using a Voltage-Divider
Figure 11. Programmable Gain/Offset Adjustment
5V VIN 30V MAX5483 MAX5484
C VOUT R3 W L R1
MAX480 MAX5483 MAX5484 L
VOUT
W MAX5483 MAX5484 L R2 W
Figure 10. Positive LCD Bias Control Using a Variable Resistor
Figure 12. Programmable Filter
Programmable Filter
Figure 12 shows the configuration for a 1st-order programmable filter using two variable resistors. Adjust R2 for the gain and adjust R3 for the cutoff frequency. Use the following equations to estimate the gain (G) and the 3dB cutoff frequency (fC):
R1 G = 1+ R2 fC = 1 2 x R3 x C
18
______________________________________________________________________________________
www..com
10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers
Selector Guide
PART MAX5481ETE MAX5481EUD MAX5482ETE MAX5482EUD MAX5483ETE MAX5483EUD MAX5484ETE MAX5484EUD CONFIGURATION Voltage-divider Voltage-divider Voltage-divider Voltage-divider Variable resistor Variable resistor Variable resistor Variable resistor END-TO-END RESISTANCE (k) 10 10 50 50 10 10 50 50
Ordering Information (continued)
PART MAX5482ETE MAX5482EUD MAX5483ETE MAX5483EUD MAX5484ETE MAX5484EUD PIN-PACKAGE 16 TQFN-EP* 14 TSSOP 16 TQFN-EP* 14 TSSOP 16 TQFN-EP* 14 TSSOP PKG CODE T1633F-3 U14-1 T1633F-3 U14-1 T1633F-3 U14-1 TOP MARK ACQ -- ACR -- ACS --
MAX5481-MAX5484
Note: All devices are specified over the -40C to +85C operating temperature range. *EP = Exposed pad.
Chip Information
TRANSISTOR COUNT: 20,029 PROCESS: BiCMOS
Pin Configurations (continued)
TOP VIEW
VDD 1 GND CS 2 3 14 VSS 13 N.C. 12 H VDD 1 GND CS 2 3 14 VSS 13 N.C. 12 D.N.C.
SCLK(INC) 4 DIN(U/D) 5 SPI/UD 6 N.C. 7
MAX5481* MAX5482*
11 W 10 L 9 8 N.C. N.C.
SCLK(INC) 4 DIN(U/D) 5 SPI/UD 6 N.C. 7
MAX5483 MAX5484
11 W 10 L 9 8 N.C. N.C.
TSSOP
*SEE FUNCTIONAL DIAGRAM
TSSOP
______________________________________________________________________________________
19
www..com
10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers MAX5481-MAX5484
Package Information
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information, go to www.maxim-ic.com/packages.)
12x16L QFN THIN.EPS
L
MARKING
E E/2
(ND - 1) X e
(NE - 1) X e
D2/2
D/2 D
AAAA
C L
e D2
k
b E2/2
0.10 M C A B
C L
L
E2
0.10 C
0.08 C A A2 A1 L
C L
C L
e
e
PACKAGE OUTLINE 8, 12, 16L THIN QFN, 3x3x0.8mm
21-0136
I
1 2
PKG REF. A b D E e L N ND NE A1 A2 k 0.25 0 0.35
8L 3x3 MIN. NOM. MAX. 0.70 0.25 2.90 2.90 0.75 0.30 3.00 3.00 0.55 8 2 2 0.02 0.20 REF 0.25 0.05 0 0.80 0.35 3.10 3.10 0.75
12L 3x3 MIN. NOM. MAX. 0.70 0.20 2.90 2.90 0.45 0.75 0.25 3.00 3.00 0.55 12 3 3 0.02 0.20 REF 0.25 0.05 0 0.80 0.30 3.10 3.10 0.65
16L 3x3 MIN. NOM. MAX. 0.70 0.20 2.90 2.90 0.30 0.75 0.25 3.00 3.00 0.40 16 4 4 0.02 0.20 REF 0.05 0.80 0.30 3.10 3.10 0.50 PKG. CODES TQ833-1 T1233-1 T1233-3 T1233-4 T1633-2 T1633F-3 T1633FH-3 T1633-4 T1633-5
EXPOSED PAD VARIATIONS
D2 MIN. 0.25 0.95 0.95 0.95 0.95 0.65 0.65 0.95 0.95 NOM. 0.70 1.10 1.10 1.10 1.10 0.80 0.80 1.10 1.10 MAX. 1.25 1.25 1.25 1.25 1.25 0.95 0.95 1.25 1.25 MIN. 0.25 0.95 0.95 0.95 0.95 0.65 0.65 0.95 0.95 E2 NOM. 0.70 1.10 1.10 1.10 1.10 0.80 0.80 1.10 1.10 MAX. 1.25 1.25 1.25 1.25 1.25 0.95 0.95 1.25 1.25 PIN ID 0.35 x 45 0.35 x 45 0.35 x 45 0.35 x 45 0.35 x 45 0.225 x 45 0.225 x 45 0.35 x 45 0.35 x 45 JEDEC WEEC WEED-1 WEED-1 WEED-1 WEED-2 WEED-2 WEED-2 WEED-2 WEED-2
0.65 BSC.
0.50 BSC.
0.50 BSC.
NOTES: 1. 2. 3. 4. DIMENSIONING & TOLERANCING CONFORM TO ASME Y14.5M-1994. ALL DIMENSIONS ARE IN MILLIMETERS. ANGLES ARE IN DEGREES. N IS THE TOTAL NUMBER OF TERMINALS. THE TERMINAL #1 IDENTIFIER AND TERMINAL NUMBERING CONVENTION SHALL CONFORM TO JESD 95-1 SPP-012. DETAILS OF TERMINAL #1 IDENTIFIER ARE OPTIONAL, BUT MUST BE LOCATED WITHIN THE ZONE INDICATED. THE TERMINAL #1 IDENTIFIER MAY BE EITHER A MOLD OR MARKED FEATURE. DIMENSION b APPLIES TO METALLIZED TERMINAL AND IS MEASURED BETWEEN 0.20 mm AND 0.25 mm FROM TERMINAL TIP. ND AND NE REFER TO THE NUMBER OF TERMINALS ON EACH D AND E SIDE RESPECTIVELY. DEPOPULATION IS POSSIBLE IN A SYMMETRICAL FASHION. COPLANARITY APPLIES TO THE EXPOSED HEAT SINK SLUG AS WELL AS THE TERMINALS. DRAWING CONFORMS TO JEDEC MO220 REVISION C. MARKING IS FOR PACKAGE ORIENTATION REFERENCE ONLY. NUMBER OF LEADS SHOWN ARE FOR REFERENCE ONLY. WARPAGE NOT TO EXCEED 0.10mm.
5. 6. 7. 8. 9. 10. 11. 12.
PACKAGE OUTLINE 8, 12, 16L THIN QFN, 3x3x0.8mm
21-0136
I
2 2
20
______________________________________________________________________________________
www..com
10-Bit, Nonvolatile, Linear-Taper Digital Potentiometers
Package Information (continued)
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information, go to www.maxim-ic.com/packages.)
TSSOP4.40mm.EPS
PACKAGE OUTLINE, TSSOP 4.40mm BODY
MAX5481-MAX5484 MAX5481-MAX5484
21-0066
I
1 1
Revision History
Pages changed at Rev 3: 1, 11, 19, 20, 21
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 21 (c) 2007 Maxim Integrated Products is a registered trademark of Maxim Integrated Products, Inc.

▲Up To Search▲

Price & Availability of MAX5481

	To Download MAX5481 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .