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19-1438; Rev 0; 3/99
NUAL KIT MA T ATION A SHEE EVALU S DAT OLLOW F
Wireless and Satellite Handset Power-Management ICs
Features
o 90% Efficient, 500mA Step-Down Converter o Two 100mA DAC-Controlled LDOs One 200mA DAC-Controlled LDO One 20mA DAC-Controlled LDO o 3 to 6-Cell NiCd or NiMH Operation 1 or 2-Cell Li-Ion Operation o +2.7V to +12V Input Voltage Range o 250A Standby (PFM) Quiescent Current o 5A Shutdown Current o I2C-Compatible Serial Interface o Selectable 375kHz, 535kHz, 670kHz, 925kHz (or Synchronizable) Switching Frequency o Power-On Reset and Start-Up Timer o Thermal Overload Protection o Pushbutton On/Off Control o Space-Saving 32-Pin TQFP Package (7mm x 7mm)
General Description
The MAX886/MAX888 power-management ICs are complete power systems for wireless and satellite handsets. The devices operate from 3 to 6-cell NiCd/NiMH batteries or from 1 or 2-cell Li-Ion batteries. They incorporate a high-efficiency, step-down DC-DC converter, a regulated 5V charge pump, and four linear regulators. The regulators supply power to the SIM, LCD, BB, DSP, and RF sections of a cellular telephone handset. The step-down converter and linear regulator outputs are adjustable by internal 4-bit DACs, programmable through the I2CTMcompatible serial interface. A pushbutton on/off scheme activates a 5A low-power shutdown mode. The devices also feature a low-battery detector output and an internal start-up timer. The MAX886/MAX888 differ in output voltage range and power-on reset voltage. The MAX886 has a higher preset voltage range and is intended for 2-cell Li-Ion or 5/6-cell NiCd/NiMH batteries. The MAX888 has a lower preset voltage range and is intended for 1-cell Li-Ion or 3/4-cell NiCd/NiMH batteries. Both devices are available in a space-saving, 32-pin TQFP package.
MAX886/MAX888
Applications
Satellite Phones Wireless Handsets Private Mobile Radio (PMR) GSM Cellular/PCS Telephones
PART MAX886ECJ* MAX888ECJ
Ordering Information
TEMP. RANGE -40C to +85C -40C to +85C PIN-PACKAGE 32 TQFP 32 TQFP
Pin Configuration appears at end of data sheet.
* Future product--contact factory for availability.
Typical Operating Circuit
IN 2.7V TO 12V BATT LX PGND LOW-BATTERY DETECT I2C-COMPATIBLE SERIAL INTERFACE ON/OFF CONTROL (OPTIONAL) LBI LBO SCL SDA ON OFF SYNC C+ CGND OUT1 OUT2 RESET OUT3 OUT4 OUT5 ONSTAT Tx SECTION POWER (UP TO 100mA) DSP POWER (UP TO 200mA) POWER-ON RESET 3V/5V SIM CARD POWER (UP TO 20mA) LCD/VCO/TXCO POWER (UP TO 100mA) Rx SECTION POWER (UP TO 100mA) ON STATUS MAIN POWER (UP TO 500mA)
MAX886 MAX888
OUT0
I2C is a trademark of Philips Corp.
________________________________________________________________ Maxim Integrated Products 1
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800. For small orders, phone 1-800-835-8769.
Wireless and Satellite Handset Power-Management ICs MAX886/MAX888
ABSOLUTE MAXIMUM RATINGS
BATT, IN0, IN1 to GND...........................................-0.3V to +13V CVH to IN0................................................................-6V to +0.3V PGND, DGND to GND...........................................-0.3V to +0.3V ONSTAT to GND .....................................-0.3V to (VOUT2 + 0.3V) LX to PGND.............................................-0.3V to (VOUT0 + 0.3V) OUT1 to GND.............................................-0.3V to (VIN1 + 0.3V) OUT2 to GND.............................................-0.3V to (VIN2 + 0.3V) OUT3 to GND.............................................-0.3V to (VIN3 + 0.3V) OUT5 to GND.............................................-0.3V to (VIN5 + 0.3V) SYNC, RESET, SCL, SDA, CVL, LBI, LBHYS, OUT0 REF, LBO, C+, C-, OUT4, IN2, IN3, IN4, IN5, ON, OFF to GND ...................................................-0.3V to +6V Continuous Power Dissipation (TA = +70C) TQFP (derate 11.1mW/C above +70C) ......................889mW Operating Temperature Range. ......................... -40C to +85C Junction Temperature ......................................................+150C Storage Temperature Range .............................-65C to +150C Lead Temperature (soldering, 10sec) .............................+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
(VBATT = VIN0 = VIN1 = +5.5V, GND = PGND = DGND, V OFF = VSYNC = 2.8V, VIN2 = VIN3 = VIN4 = VIN5 = +3.8V, VOUT4 = +5.5V, TA = -40C to +85C, unless otherwise noted. Typical values are at TA = +25C.) (Note 1) PARAMETER BATT, IN0, IN1 Operating Voltage Range IN2, IN3, IN4, IN5 Operating Voltage Range Undervoltage Lockout Supply Current, PFM Mode SYMBOL VBATT, VIN0, VIN1 VIN2, VIN3, VIN4, VIN5 VUVLOF VUVLOR IBATTPFM VBATT falling VBATT rising SYNC = GND fOSC = 375kHz Supply Current, PWM Mode IBATTPWM fOSC = 535kHz fOSC = 670kHz fOSC = 925kHz Supply Current, Shutdown Mode REFERENCE Reference Output Voltage Reference Load Regulation Reference Supply Rejection DC-DC BUCK REGULATOR 0 (IN0, OUT0) Input Voltage Range Output Accuracy Nominal Output Adjustment Range Output Ready Threshold VOUT0 VIN0 IOUT0 = 0 MAX886 MAX888 VOUT0 = 3.75V (MAX886), VOUT0 = 2.027V (MAX888) 2.7 -3 2.625 1.527 -7.5 -5 12 3 3.750 3.027 -3 V % V % of VOUT0 VREF IREF = 0 1A < IREF < 100A 2.7V < VOUT0 < 3.75V TA = 0C to +85C TA = -40C to +85C 1.23 1.225 5 0.2 1.25 1.27 1.275 15 5 V mV mV ISTNBY OFF = GND TA = 0C to +85C TA = -40C to +85C CONDITIONS MIN 2.7 2.7 2.35 2.45 2.55 250 2 3 4 5.5 5 12 10 15 A mA 2.65 600 TYP MAX 12 5.5 UNITS V V V V A
2
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Wireless and Satellite Handset Power-Management ICs
ELECTRICAL CHARACTERISTICS (continued)
(VBATT = VIN0 = VIN1 = +5.5V, GND = PGND = DGND, V OFF = VSYNC = 2.8V, VIN2 = VIN3 = VIN4 = VIN5 = +3.8V, VOUT4 = +5.5V, TA = -40C to +85C, unless otherwise noted. Typical values are at TA = +25C.) (Note 1) PARAMETER Output Load Regulation Line Regulation Maximum Duty Cycle LX Leakage Current Internal Switch On-Resistance PFM to PWM Threshold Internal Switch Current Limit ILIMIT TA = 0C to +85C TA = -40C to +85C OSCILLATOR FREQUENCY (OUT0, OUT4) Oscillator Frequency Accuracy SYNC Range LDO REGULATOR 1 (IN1, OUT1) Input Voltage Range Output Accuracy Nominal Output Adjustment Range Dropout Voltage Output Load Regulation Line Regulation Current Limit LDO REGULATOR 2 (IN2, OUT2) Input Voltage Range Output Accuracy Nominal Output Adjustment Range Output Ready Threshold Dropout Voltage Output Load Regulation Line Regulation Current Limit LDO REGULATOR 3 (IN3, OUT3) Input Voltage Range Output Accuracy VIN3 IOUT3 = 0.1mA to 20mA 2.7 -3 5.5 3 V % VOUT2 VRDY2 VIN2 IOUT2 = 0.1mA to 200mA MAX886 MAX888 VOUT2 = 3.3V (MAX886), VOUT2 = 1.527V (MAX888) IOUT2 = 1mA IOUT2 = 200mA IOUT2 = 0.1mA to 200mA 2.7V < VIN2 < 3.8V, 0h code -0.005 -0.3 200 500 2.7 -3 2.175 1.527 -7.5 -5 1 90 200 0.002 0.3 5.5 3 3.30 3.027 -3 V % V % of VOUT2 mV %/mA %/V mA VOUT1 VIN1 IOUT1 = 0.1mA to 100mA MAX886 MAX888 IOUT1 = 1mA IOUT1 = 100mA IOUT1 = 0.1mA to 100mA 3V < VIN1 < 12V, 0h code -0.01 -0.1 100 0 250 2.7 -3 2.70 1.25 1 90 200 0.01 0.1 12 3 4.95 3.5 V % V mV %/mA %/V mA fOSC Table 4 -20 -23 0.8 * fOSC fOSC 20 23 1.2 * fOSC % kHz RON SYMBOL CONDITIONS IOUT0 = 0.1mA to 500mA 3V < VIN0 < 12V VLX = 12V VLX = 12V VIN0 = 3.8V IOUT0 63 0.6 -0.3 100 0.1 0.4 98 0.9 10 1 180 1.2 MIN TYP -1.5 0 0.3 MAX UNITS % % % A mA A
MAX886/MAX888
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Wireless and Satellite Handset Power-Management ICs MAX886/MAX888
ELECTRICAL CHARACTERISTICS (continued)
(VBATT = VIN0 = VIN1 = +5.5V, GND = PGND = DGND, V OFF = VSYNC = 2.8V, VIN2 = VIN3 = VIN4 = VIN5 = +3.8V, VOUT4 = +5.5V, TA = -40C to +85C, unless otherwise noted. Typical values are at TA = +25C.) (Note 1) PARAMETER SYMBOL VIN3 = 5.5V, Table 5 IOUT3 = 1mA IOUT3 = 20mA IOUT3 = 0.1mA to 20mA 3.8V < VIN3 < 5.5V, VOUT3 = 2.85V VOUT3 = 2.85V or 4.65V only -0.035 -0.3 20 50 fOSC / 2 VOUT4 No load IOUT4 = 50mA 2.7 IOUT5 = 0.1mA to 100mA VOUT5 MAX886 MAX888 IOUT5 = 1mA IOUT5 = 100mA IOUT5 = 0.1mA to 100mA 2.7V < VIN5 < 3.8V, 0h code -0.01 -0.3 100 VLBI = 1.23V -0.2 VREF 15mV VLBI = step from 1.23V to 1.27V V LBO = ILBHYS = 1mA, VLBI = VREF - 15mV V LBO = VLBHYS = 12V, VLBI = VREF + 15mV -0.2 VREF 10 0.5 0.2 250 0.2 VREF + 15mV -3 2.175 1.25 1 72 200 0.01 0.3 5.10 5.25 5.21 5.5 3 3.300 3.50 5.41 CONDITIONS MIN TYP 0 Nominal Output Voltage VOUT3 2.85 4.65 VOUT2 Dropout Voltage Output Load Regulation Line Regulation Current Limit CHARGE-PUMP REGULATOR 4 (IN4, OUT4) Switching Frequency Output Voltage LDO REGULATOR 5 (IN5, OUT5) Input Voltage Range Output Accuracy Nominal Output Adjustment Range Dropout Voltage Output Load Regulation Line Regulation Current Limit LOW-BATTERY COMPARATOR LBI Input Current LBI Threshold LBI Propagation Delay LBO/LBHYS Output Low Voltage LBO/LBHYS Leakage Current RESET AND START-UP TIMER Reset Timeout Period Start-Up Timeout Period LOGIC AND CONTROL INPUTS ON Input Voltage VIL VIH 1.2 0.4 V 56 28 75 37 94 47 ms ms A V s V A VIN5 V % V mV %/mA %/V mA kHz V 1 20 50 0.02 0.3 mV %/mA %/V mA V MAX UNITS
4
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Wireless and Satellite Handset Power-Management ICs
ELECTRICAL CHARACTERISTICS (continued)
(VBATT = VIN0 = VIN1 = +5.5V, GND = PGND = DGND, V OFF = VSYNC = 2.8V, VIN2 = VIN3 = VIN4 = VIN5 = +3.8V, VOUT4 = +5.5V, TA = -40C to +85C, unless otherwise noted. Typical values are at TA = +25C.) (Note 1) PARAMETER ON Input Current SYNC Input Voltage SYNC Input Current ONSTAT OUTPUT ONSTAT Output Voltage ONSTAT Output Voltage RESET OUTPUT Output Low Voltage Output High Voltage THERMAL SHUTDOWN Threshold Temperature I2C-COMPATIBLE SCL Low Period SCL High Period Data Set-Up Time Data Hold Time OFF, SDA, SCL Input Voltage OFF, SDA, SCL Input Current SDA Output Low Voltage LBO, LBHYS Leakage Current SERIAL INTERFACE fSCL tLOW tHIGH tDSU tDHOLD VIL VIH IILH 0 < VILH < VOUT2 ISDA = 3mA ISDA = 6mA V LBO = VLBHYST = 12V, VLBI = VREF + 15mV -0.2 1.4 1 0.4 0.6 0.2 1.3 0.6 100 0 0.9 0.6 400 kHz s s ns s V A V A SCL Clock Frequency 160 C V RESETL V RESETH I RESET = 1mA I RESET = 0, internal 10k pull-up resistor to OUT2 VOUT2 0.5 0.5 V V VONSTATL VONSTATH IONSTAT = 1mA IONSTAT = 0 VOUT2 0.5 0.5 V V SYMBOL IIL IIH VIL VIH ISYNC 0 < VSYNC < VOUT2 2.0 0.25 1 V ON = 0 1.2V < V ON < VOUT2 CONDITIONS MIN TYP -16 -5 MAX -40 -10 0.8 UNITS A V A
MAX886/MAX888
Note 1: Specifications to -40C are guaranteed by design, not production tested.
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Wireless and Satellite Handset Power-Management ICs MAX886/MAX888
Typical Operating Characteristics
(Circuit of Figure 2, REG0 to REG5 outputs at POR states, VOUT0 = 3.75V, VOUT4 = 5.25V, VOUT1 = VOUT2 = VOUT3 = VOUT5 = 3.3V, TA = +25C, unless otherwise noted.)
MAX886 REG0 EFFICIENCY vs. LOAD CURRENT (VBATT = 8.4V)
MAX886/88-01
MAX886 REG0 EFFICIENCY vs. LOAD CURRENT (VBATT = 5.4V)
PFM, 375kHz 90 EFFICIENCY (%) PFM, 925kHz PWM, 925kHz PWM, 375kHz
MAX886/88-02
MAX886 NO-LOAD BATTERY CURRENT vs. BATTERY VOLTAGE
9 8 BATTERY CURRENT (mA) 7 6 5 4 3 2 1 PFM MODE 2 3 4 5 6 7 8 9 10 11 12 PWM, 375kHz PWM, 925kHz
MAX886/88-03
100 PFM, 925kHz PFM, 375kHz EFFICIENCY (%) 80 PWM, 375kHz
100
10
90
80
70 PWM, 925kHz 60
70
60
50 1 10 100 1,000 LOAD CURRENT (mA)
50 1 10 100 1,000 LOAD CURRENT (mA)
0 BATTERY VOLTAGE (V)
MAX888 REG0 EFFICIENCY vs. LOAD CURRENT (VBATT = 4.2V)
MAX886/88-04
MAX888 REG0 EFFICIENCY vs. LOAD CURRENT (VBATT = 2.7V)
PFM, 925kHz PFM, 375kHz PWM, 375kHz 80 PWM, 925kHz 70
MAX886/88-05
MAX888 NO LOAD BATTERY CURRENT vs. BATTERY VOLTAGE
MAX886/88-06
100 PFM, 375kHz PFM, 925kHz EFFICIENCY (%) 80 PWM, 925kHz 70 PWM, 375kHz
100
7 6 BATTERY CURRENT (mA) 5 4 3 PWM, 375kHz 2 1 PFM MODE 2 3 4 BATTERY VOLTAGE (V) 5 6 PWM, 925kHz
90
90 EFFICIENCY (%)
60
60
50 1 10 100 1,000 LOAD CURRENT (mA)
50 1 10 100 1,000 LOAD CURRENT (mA)
0
DROPOUT VOLTAGE vs. LOAD CURRENT
VIN1 = VIN2 = VIN5 = 3.3V VIN3 = 2.85V REG1 REG5
MAX886/88-07
REG4 OUTPUT VOLTAGE vs. LOAD CURRENT
MAX886/88-08
SHUTDOWN CURRENT vs. BATTERY VOLTAGE
9 SHUTDOWN CURRENT (A) 8 7 6 5 4 3 2 1 0 R1, R2, R3 NOT CONNECTED
MAX886/88-09
140 120 DROPOUT VOLTAGE (mV) 100 80 60 40 20 0 0 REG3 REG2
5.28 5.26 OUTPUT VOLTAGE (V) 5.24 5.22 5.20 5.18 5.16 5.14 5.12 VIN4 = 3.75V
10
20 40 60 80 100 120 140 160 180 200 LOAD CURRENT (mA)
0
20
40
60
80
100
2
3
4
5
6
7
8
9
10 11 12
LOAD CURRENT (mA)
BATTERY VOLTAGE (V)
6
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Wireless and Satellite Handset Power-Management ICs
Typical Operating Characteristics (continued)
(Circuit of Figure 2, REG0 to REG5 outputs at POR states, VOUT0 = 3.75V, VOUT4 = 5.25V, VOUT1 = VOUT2 = VOUT3 = VOUT5 = 3.3V, TA = +25C, unless otherwise noted.)
REG1 POWER-SUPPLY REJECTION RATIO vs. FREQUENCY
MAX886/88-10
MAX886/MAX888
REG2 POWER-SUPPLY REJECTION RATIO vs. FREQUENCY
VOUT2 = 3.3V IOUT2 = 20mA COUT2 = 2.2F
MAX886/88-11
REG0 TURN-ON DELAY
MAX886/88-12
70 60 50 PSRR (dB) 40 30 20 10 0 0.01 0.1 1 10 100 VOUT1 = 3.3V IOUT1 = 10mA COUT1 = 2.2F
70 60 50 PSRR (dB) 40 30 20 10 0
VON (2V/div)
VOUT0 (2V/div)
1,000
0.01
0.1
1
10
100
1,000 IOUT0 = 20mA
400s/div
FREQUENCY (kHz)
FREQUENCY (kHz)
REG0 LINE-TRANSIENT RESPONSE (PWM MODE)
MAX886/88-13
REG0 LINE-TRANSIENT RESPONSE (PFM MODE)
MAX886/88-14
REG2 LINE-TRANSIENT RESPONSE (IN2 CONNECTED TO OUT0)
MAX886/88-15
VBATT (500mV/div)
VBATT (500mV/div)
VBATT (500mV/div)
VOUT0 (100mV/div)
VOUT0 (100mV/div)
VOUT2 (100mV/div)
400s/div VBATT = 7V TO 8V, IOUT0 = 500mA, VOUT0 = 3.75V, AC-COUPLED
400s/div VBATT = 7V TO 8V, IOUT0 = 5mA, VOUT0 = 3.75V, AC-COUPLED
400s/div VBATT = 7V TO 8V, IOUT2 = 5mA, VOUT2 = 3.3V, AC-COUPLED
REG0 LOAD-TRANSIENT RESPONSE (PWM MODE)
MAX886/88-16
REG0 LOAD-TRANSIENT RESPONSE (PFM MODE)
MAX886/88-17
REG2 LOAD-TRANSIENT RESPONSE (IN2 CONNECTED TO BATT)
MAX886/88-18
IOUT0 (200mA/div)
IOUT0 (200mA/div)
IOUT2 (200mA/div)
VOUT0 (100mV/div)
VOUT0 (100mV/div)
VOUT2 (100mV/div)
400s/div VBATT = 5.4V, IOUT0 = 0 TO 500mA, VOUT0 = 3.75V, AC-COUPLED
400s/div VBATT = 5.4V, IOUT0 = 0 TO 500mA, VOUT0 = 3.75V, AC-COUPLED
400s/div VBATT = VIN2 = 5.4V, IOUT2 = 0 TO 200mA, VOUT2 = 3.3V, AC-COUPLED
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Wireless and Satellite Handset Power-Management ICs MAX886/MAX888
Pin Description
PIN 1 2 3 4 5 6 7 8 9 10 11 12 13 NAME LX PGND OUT0 CVL REF GND BATT OUT4 C+ IN4 CDGND LBI FUNCTION Inductor Input. Drain of the internal p-channel MOSFET. Power Ground Switching Regulator 0 Output. Bypass with a 10F, low-ESR capacitor to PGND. Up to 500mA is available from OUT0. Low-Side Drive Bypass. Bypass with a 1F capacitor to GND. Reference Output. Bypass with a 0.22F capacitor to GND. REF can source up to 100A. Ground Supply Voltage Input. Bypass with a 0.1F and a 10F capacitor to PGND as close to BATT as possible. Charge-Pump Regulator 4 Output. Bypass with a 10F, low-ESR capacitor to DGND. Charge-Pump Capacitor Positive Connection Regulator 4 Power-Supply Input Charge-Pump Capacitor Negative Connection Digital Ground Low-Battery Detector Input. LBO goes low when VLBI drops below VREF. Connect LBI to the center of a resistor voltage divider between BATT and GND. Low-Battery Detector Hysteresis Control. An open-drain output to set the hysteresis of the Low-Battery Detector Comparator. Low-Battery Output. Open-drain output of the Low-Battery Detector Comparator. LBO is high impedance when device is shutdown or VLBI > VREF. V LBO is low when VLBI < VREF. Typically, connect a 200k pullup resistor between LBO and OUT2. Reset Output. RESET remains low during initial power-up for 75ms after OUT2 is ready. RESET has an internal 10k pull-up resistor connected to OUT2. RESET is valid for VBATT down to 1V. Linear Regulator 2 Power-Supply Input Linear Regulator 2 Output. Bypass with a 2.2F, low-ESR capacitor to GND. Up to 200mA is available from OUT2. The reset circuit monitors this voltage. Linear Regulator 3 Output. Bypass with a 1F, low-ESR capacitor to GND. Up to 20mA is available from OUT3. Regulator 3 Power-Supply Input Regulator 5 Power-Supply Input Linear Regulator 5 Output. Bypass with a 1F, low-ESR capacitor to GND. Up to 100mA is available from OUT5. Regulator 1 Power-Supply Input
14
LBHYS
15
LBO
16 17 18
RESET IN2 OUT2
19 20 21 22 23
OUT3 IN3 IN5 OUT5 IN1
8
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Wireless and Satellite Handset Power-Management ICs
Pin Description (continued)
PIN 24 NAME OUT1 FUNCTION Linear Regulator 1 Output. Bypass with a 2.2F, low-ESR capacitor to GND. Up to 100mA is available from OUT1. Power-Off Input. Drive OFF high before the start-up timer has expired in order to keep the IC powered on. Drive OFF low to shut down the IC. OFF has an internal 100k pull-down resistor to GND. Power-On Input. Pulse the ON pin low to turn on the IC. ON has an internal 16A pull-up. ON Status Output. Push/pull logic output indicating the state of the ON input. The logic state of this pin follows the logic state of the ON pin. The logic high output voltage is the output voltage of OUT2. Serial Interface Data Input Serial Interface Clock Input Sync Input. Drive SYNC with a logic-level square wave to synchronize the internal oscillator. The capture range for external clock is 20% of the selected internal oscillator frequency. Drive SYNC low for more than 10s to force low-power PFM mode (standby mode). Drive SYNC high to force PWM mode. High-Side Drive Bypass Input. Bypass CVH with a 0.1F capacitor connected to IN0. Regulator 0 Power-Supply Input. Connect to BATT. Source of the internal p-channel MOSFET.
MAX886/MAX888
25 26 27 28 29 30 31 32
OFF ON ONSTAT SDA SCL SYNC CVH IN0
A
tLOW
B
tHIGH
C
D
E
F
G
H
I
J
K
L
M
SCL
SDA
tSU:STA
tHD:STA
tSU:DAT
tHD:DAT F = ACKNOWLEDGE BIT CLOCKED INTO MASTER G = MSB OF DATA CLOCKED INTO SLAVE (OP/SUS BIT) H = LSB OF DATA CLOCKED INTO SLAVE I = SLAVE PULLS SMBDATA LINE LOW
tSU:STO tBUF J = ACKNOWLEDGE CLOCKED INTO MASTER K = ACKNOWLEDGE CLOCK PULSE L = STOP CONDITION, DATA EXECUTED BY SLAVE M = NEW START CONDITION
A = START CONDITION B = MSB OF ADDRESS CLOCKED INTO SLAVE C = LSB OF ADDRESS CLOCKED INTO SLAVE D = R/W BIT CLOCKED INTO SLAVE E = SLAVE PULLS SMBDATA LINE LOW
Figure 1. I2C-Compatible Serial-Interface Timing Diagram
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Wireless and Satellite Handset Power-Management ICs MAX886/MAX888
IN 4V TO 12V L1 10H C1 10F C2 0.1F BATT LX PGND OUT0 IN2 IN4 D1 MBR0520L C11 10F OUT0 UP TO 500mA
IN0 R1 1.1M C4 0.1F IN1 CVH LBI R2 562k LBHYS R3 23.3k GND
MAX886
IN5 OUT1 OUT1 C7 UP TO 100mA 2.2F OUT2 C8 UP TO 200mA 2.2F
OUT2 R5 200k LBO
C5 0.22F
REF
C3 1F
CVL
RESET
C+ C6 0.22F C-
OUT3
OUT3 C9 UP TO 20mA 1F OUT4 C12 5.25V UP TO 100mA 10F
OUT4 SCL IN3 SDA OUT5
ON OFF
OUT5 C10 UP TO 100mA 1F
SYNC DGND
ONSTAT
Figure 2a. Typical 2 Li+ or 5 to 6 Ni-Cell Application Circuit (MAX886)
10
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Wireless and Satellite Handset Power-Management ICs MAX886/MAX888
IN 2.7V TO 5.5V L1 10H C1 10F C2 0.1F BATT LX PGND OUT0 IN2 IN4 D1 MBR0520L C11 10F OUT0 UP TO 500mA
IN0 R1 619k C4 0.1F IN1 CVH LBI R2 562k LBHYS R3 47.6k GND
MAX888
IN5 OUT1 OUT1 C7 UP TO 100mA 2.2F OUT2 C8 UP TO 200mA 2.2F
OUT2 R5 200k LBO
C5 0.22F
REF
C3 1F
CVL
RESET
C+ C6 0.22F C-
OUT3
OUT3 C9 UP TO 20mA 1F OUT4 C12 5.25V UP TO 100mA 10F
OUT4 SCL IN3 SDA OUT5
ON OFF
OUT5 C10 UP TO 100mA 1F
SYNC DGND
ONSTAT
Figure 2b. Typical 1 Li+ or 3 to 4 Ni-Cell Application Circuit (MAX888)
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Wireless and Satellite Handset Power-Management ICs MAX886/MAX888
Detailed Description
The MAX886/MAX888 contain one high-efficiency, stepdown DC-DC converter, four low-dropout linear regulators, and one regulated charge pump. The output voltages of the switching regulator and the linear regulators are software-programmable through the serial interface. The regulated charge-pump output is factory set at 5.25V. The devices also include reset and start-up timers and a low-battery detect comparator (Figure 3).
5 ON1 SDA SCL DAC1 LOGIC DECODER DAC2 ON2 ON2 DAC3 LINEAR REG1 LINEAR REG2 LINEAR REG3 LINEAR REG5 IN1 OUT1
500mA DC-DC Buck Regulator 0
Regulator 0 is a low-noise, step-down, synchronous DC-DC converter that can source a minimum of 500mA. High operating frequency (up to 925kHz) minimizes output voltage ripple and reduces the size and cost of external components. Guaranteed 100% dutycycle operation provides the lowest possible dropout voltage, extending the useful life of the battery supply.
IN2 OUT2 IN3 OUT3 IN5 OUT5 CVH CVL IN0 BATT
DAC5 ON5
LX DAC0 SYNC OUT2 OSCILLATOR 10k RESET ON OFF LBI LBO REF LBHYS REF RESET AND START UP TIMER ON4 REG4 CHARGE PUMP REGULATOR ON0 + SWITCHING REGULATOR PGND IN4 OUT4 C+ COUT0
ONSTAT
DGND GND
Figure 3. Functional Diagram
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Wireless and Satellite Handset Power-Management ICs
The serial interface programs V OUT0 from 2.625V to 3.75V in 75mV steps for the MAX886 (Tables 1 and 2), or from 1.527V to 3.027V in 100mV steps for the MAX888 (Tables 1 and 3). Regulator 0 operates in one of four preset frequencies, from 375kHz to 925kHz, programmable through the serial interface (Table 4). For the device to power up properly, VIN0 must be high enough for REG0 to get into regulation. For the MAX886, Regulator 0's default voltage is 3.75V. Since the rest of the regulators do not power up until Regulator 0 is ready, VIN0 must be greater than approximately 4V for the device to power up properly. The Regulator 0 default voltage for the MAX888 is 2.027V, so the minimum VIN0 required to start up is limited by the minimum operating voltage range (2.7V). After power-up, the device operates until VBATT drops below V UVLOF (undervoltage lockout falling threshold). zero. In PFM mode, the inductor current does not go negative to discharge the output. At no-load there is a long period between pulses of inductor current. As the load current increases, the period between pulses becomes shorter until the pulses become continuous. At load currents above this point, Regulator 0 automatically switches to PWM mode, and the VLX waveform looks like a square wave whose duty cycle depends on the input and output voltages. As the input voltage approaches the same level as the output voltage, the P-channel switch stays on 100% of the time, providing the lowest possible dropout. It is typically more efficient to use the PFM mode when the load current is less than 100mA.
MAX886/MAX888
100mA LDO Regulator 1
Regulator 1, a low-dropout linear regulator, sources a minimum of 100mA and operates from voltages at IN1 of up to 12V. The serial interface programs VOUT1 from 2.7V to 4.95V in 75mV steps for the MAX886 (Tables 1 and 2), or from 1.25V to 3.50V in 150mV steps for the MAX888 (Tables 1 and 3). IN1 may be powered from the battery, OUT0, or any other voltage source.
Sync Mode The SYNC input allows the MAX886/MAX888 to synchronize with an external clock applied to SYNC, ensuring that switching harmonics are kept away from sensitive IF bands. The SYNC detector triggers on SYNC's falling edge. PWM Mode Regulator 0 is in PWM mode when SYNC is connected to CVL or driven to a logic-high voltage. Two internal switches operate at a preset frequency even when there is no load. The P-channel MOSFET turns on to charge the inductor until the error comparator or current-limit comparator turns it off. The N-channel MOSFET then turns on to discharge the inductor. To prevent the output from soaring with no load in PWM mode, the N-channel switch stays on long enough to allow the inductor current to go negative. Once the N-channel switch turns off, the voltage at LX rises (rings) until the next cycle when the P-channel switch turns on again. As the load increases and the inductor enters continuous conduction, ringing is no longer present and the LX waveform looks like a square wave whose duty cycle depends on the input and output voltages. As the input voltage approaches the same level as the output voltage, the P-channel switch stays on 100% of the time, providing the lowest possible dropout. PFM Mode Regulator 0 operates in PFM mode when SYNC is driven to a logic low voltage or connected to GND. When V OUT0 drops below the regulation threshold, the Pchannel switch turns on to charge the inductor until the error comparator or current-limit comparator turns it off. At light loads, the N-channel then turns on to discharge the inductor until the current in the inductor reaches
200mA LDO Regulator 2
Regulator 2, a low-dropout linear regulator, sources a minimum of 200mA. The serial interface programs VOUT2 from 2.175V to 3.3V in 75mV steps for the MAX886 (Tables 1 and 2), or from 1.527V to 3.027V in 100mV steps for the MAX888 (Tables 1 and 3). IN2 may be powered from the battery, OUT0, or any other voltage source less than 5.5V.
20mA LDO Regulator 3
Regulator 3, a low-dropout linear regulator, sources a minimum of 20mA. The serial interface programs VOUT3 to one of four different output voltages: 0V, 2.85V, 4.65V, or VOUT2 (Tables 1 and 5). Although this is a generalpurpose output, OUT3 is intended for the SIM supply. IN3 may be powered from OUT4 or from any regulated 5V supply. When programmed to 0V or VOUT2, OUT3 is either actively discharged to GND (for 0V mode) or connected to OUT2 (for VOUT2), and Regulator 3 is disabled to conserve power.
100mA Charge-Pump Regulator 4
Regulator 4, a regulated charge pump, generates 5.25V and delivers up to 100mA. An oscillator synchronized to the PWM clock regulates OUT4 to minimize noise. It operates at one-half the frequency of the PWM oscillator to ensure 50% duty-cycle outputs. IN4 may be powered from the battery, OUT0, or any other voltage source less than 5.5V. To save space and cost, use a small ceramic flying capacitor. See Table 6 for recommended flying capacitor values.
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Wireless and Satellite Handset Power-Management ICs MAX886/MAX888
100mA LDO Regulator 5
Regulator 5, a low-dropout linear regulator, can source a minimum of 100mA. The output voltage is programmable from 2.175V to 3.3V in 75mV steps for the MAX886 (Tables 1 and 2), or 1.25V to 3.50V in 150mV steps for the MAX888 (Tables 1 and 3). IN5 may be powered from the battery, OUT0, or any other voltage source less than 5.5V.
Control Data Byte
The control byte is eight bits long (four address bits, four data bits). Each regulator has a DAC that sets the output regulation voltage. Control codes are summarized in Table 1.
Table 1. Control Data Byte
ADDRESS FUNCTION OUT0 Output Voltage OUT1 Output Voltage OUT2 Output Voltage OUT3 Output Voltage, fOSC OUT5 Output Voltage OUT1, 2, 4, 5 On/Off Control OUT0 On/Off Control Not Available Not Available A3 MSB 0 0 0 0 0 0 0 0 1 A2 0 0 0 0 1 1 1 1 X A1 0 0 1 1 0 0 1 1 X A0 0 1 0 1 0 1 0 1 X ON5 X X X X X X DAC3 DAC5 ON4 ON2 X X X ON1 ON0 X X D3 D2 DAC0 DAC1 DAC2 fOSC DATA D1 D0 LSB
Table 2. MAX886 Output Voltage Settings
REGULATOR OUTPUT VOLTAGE (V) OUT5 2.175 2.250 2.325 2.400 2.475 2.550 2.625 2.700 2.775 2.850 2.925 3.000 3.075 3.150 3.225 3.300 OUT2 2.175 2.250 2.325 2.400 2.475 2.550 2.625 2.700 2.775 2.850 2.925 3.000 3.075 3.150 3.225 3.300 OUT1 2.70 2.85 3.00 3.15 3.30 3.45 3.60 3.75 3.90 4.05 4.20 4.35 4.50 4.65 4.80 4.95 OUT0 2.625 2.700 2.775 2.850 2.925 3.000 3.075 3.150 3.225 3.300 3.375 3.450 3.525 3.600 3.675 3.750 D3 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 D2 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 DACX DATA D1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 D0 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1
Note: The output voltage of each regulator can be set independently. The POR states are in boldface.
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Wireless and Satellite Handset Power-Management ICs MAX886/MAX888
Table 3. MAX888 Output Voltage Settings
REGULATOR OUTPUT VOLTAGE (V) OUT5 1.25 1.40 1.55 1.70 1.85 2.00 2.15 2.30 2.45 2.60 2.75 2.90 3.05 3.20 3.35 3.50 OUT2 1.527 1.627 1.727 1.827 1.927 2.027 2.127 2.227 2.327 2.427 2.527 2.627 2.727 2.827 2.927 3.027 OUT1 1.25 1.40 1.55 1.70 1.85 2.00 2.15 2.30 2.45 2.60 2.75 2.90 3.05 3.20 3.35 3.50 OUT0 1.527 1.627 1.727 1.827 1.927 2.027 2.127 2.227 2.327 2.427 2.527 2.627 2.727 2.827 2.927 3.027 D3 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 D2 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 DACX DATA D1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 D0 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1
Note: The output voltage of each regulator can be set independently. The POR states are in boldface.
Table 4. Oscillator Frequency Setting
ADDRESS 03h DATA fOSC (kHz) 375 535 670 925 D3 X X X X D2 X X X X D1 0 0 1 1 D0 0 1 0 1
Low-Battery Detector
A low-battery comparator detects low-battery conditions. The trip threshold is internally set to VREF (1.25V typ). LBHYS sets the hysteresis with external resistors. LBO and LBHYS have open-drain outputs. The externally set low-battery threshold must be higher than the UVLOF threshold (2.45V typical). Set the threshold and hysteresis by connecting resistors R1 (between BATT and LBI), R2 (between LBI and LBHYS), and R3 (LBHYS and GND) (Figure 2). After choosing the upper and lower thresholds, calculate the resistor values as follows: 1) Choose a value for R1. Typical values range from 500k to 1.5M. 2) Calculate R2: R2 = R1 VTHR - 1 VREF
Note: The POR states are in boldface.
Table 5. OUT3 Output Voltage Setting
ADDRESS 03h DATA 0V (REG3 Off) 2.85V 4.65V VOUT2 (REG3 Off) D3 0 0 1 1 D2 0 1 0 1 D1 X X X X D0 X X X X
3) Calculate R3: R3 =
R2 VTHF - VREF
(
)
- R1
VREF
Note: The POR states are in boldface.
VREF - VTHF
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Wireless and Satellite Handset Power-Management ICs MAX886/MAX888
For example: VREF = 1.25V VTHF = falling threshold = 2.52V VHYS = hysteresis = 0.1V VTHR = rising threshold = VTHF + VHYS = 2.62V R1 = 619k (1%) R2 = 562k (1%) R3 = 47.6k (1%)
ONSTAT Output
ONSTAT is a logic output that follows ON. Connect ONSTAT to the external logic or controller to sense when the ON pin has been brought low to request shutdown. This allows easy implementation of a one-button on/off control scheme (Figure 4).
Thermal Overload Protection
An internal thermal sensor shuts the MAX886/MAX888 down when the maximum temperature limit is exceeded (160C typical).
Power-On Sequence (Including RESET and Start-Up Timers)
Drive ON low to begin the power-up sequence. To reduce overall system cost and complexity, the MAX886/MAX888 incorporate RESET and start-up timers with the power-on sequence. The MAX886/MAX888 turn on the reference when ON goes low. Once the reference is fully powered up, if the input voltage exceeds the internal undervoltage-lockout threshold (UVLOR), Regulator 0 turns on. Once OUT0 is in regulation, OUT2 and OUT4 turn on. Once OUT2 is in regulation, OUT1 and OUT5 turn on and the 75ms reset timer begins. RESET remains low from the time OUT2 is valid until the reset timer times out. After the reset period expires, a 50ms start-up timer begins. The MAX886/MAX888 shut down if the external logic or controller fails to drive OFF high before the start-up timer expires. Drive OFF high to continue operation. Driving OFF low turns off the IC. There is no required sequence to power off any regulator after the device has turned on. Regulators can be powered off selectively by sending the correct code through the serial interface (Table 1).
I2C-Compatible Serial Interface
Use an serial interface to turn the MAX886/MAX888 on and off, as well as control each regulator's output voltage and program the DC-DC converter and charge pump's oscillator frequency. Use standard I2C-compatible receive-byte commands to program the IC. This part is always a slave to the bus master. The chip address is 1001 111. I 2 C-compatible
POR State
The power-on reset state of all the DAC and frequency registers is 0Fh, except for DAC1 which is 04h. The power-on reset state of the ONX bits is 1 (Table 1). The power-on voltage for each regulator is shown in bold in Tables 2, 3, and 5.
Applications Information
Inductor Selection
The essential parameters for inductor selection are inductance and current rating. The MAX886/MAX888 operate with a wide range of inductance values. In many applications, values between 10H and 68H take best advantage of the controller's high switching frequency. Calculate the minimum inductance value using the simplified equation:
L MIN =
MAX886 MAX888
10k
OUT2
()
(I
4 VBATT MAX - VOUT0
PEAK
fOSC
()
VBATT / VOUT0
)
RESET ON ONSTAT C
OFF
where IPEAK is the peak inductor current (0.9A) and fOSC is the switching frequency. For example, for a 6V battery voltage, a desired VOUT0 is 3.3V, the oscillator frequency is 375kHz, and 15H is the minimum inductance required.
Diode Selection
The MAX886/MAX888's high switching frequency demands a high-speed rectifier. Schottky diodes, such as the 1N5817-1N5822 family or surface-mount MBR0520L series are recommended. Ultra-high-speed rectifiers with reverse recovery times around 50ns or
Figure 4. One-Button On/Off Control with ONSTAT
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Wireless and Satellite Handset Power-Management ICs
faster, such as the MUR series, are acceptable. Ensure that the diode's peak current rating exceeds the peak current (1A), and that its breakdown voltage exceeds VBATT. Schottky diodes are preferred for heavy loads due to their low forward voltage, especially in low-voltage applications.
Table 7. Component Suppliers
COMPANY AVX Coilcraft Coiltronics Dale Internal Rectifier Motorola Sanyo Sprague Sumida PHONE 803-946-0690 847-639-6400 516-241-7876 605-668-4131 310-322-3331 602-303-5454 619-661-6835 408-988-8000 847-956-0666 FAX 803-626-3123 847-639-1469 516-241-9339 605-665-1627 310-322-3332 602-994-6430 619-661-1055 408-970-3950 847-956-0702
MAX886/MAX888
Capacitor Selection
Choose filter capacitors to service input and output peak currents with acceptable voltage ripple. The capacitor's equivalent series resistance (ESR) is a major contributor to ripple; therefore, low-ESR capacitors are recommended for OUT1-OUT5. A tantalum capacitor is recommended for OUT0 (refer to Figures 2a and 2b, and Table 6). The input filter capacitor reduces peak currents drawn from the power source, and reduces noise and voltage ripple on the input, which are caused by the circuit's switching action. Since the current from the battery is interrupted each time the PMOS switch opens, pay special attention to the ripple current rating of the input filter capacitor and use a low-ESR capacitor. Choose input capacitors with working voltage ratings higher than the maximum input voltage. Input capacitors prevent spikes and ringing on the power source from obscuring the current-feedback signal and causing jitter. Bypass REF with 0.22F to GND. The capacitor should be placed within 0.2 inches of the IC, next to REF, with a direct trace to GND.
Layout Considerations
High-frequency switching regulators are sensitive to PC board layout. Poor layout introduces switching noise into the current and voltage-feedback signals, resulting in jitter, instability, or degraded performance. Place the anode of the Schottky diode and the ground pins of the input and output capacitors close together, and route them to a common "star-ground" point. Place components and route ground paths so as to prevent high currents from causing large voltage gradients between the ground pin of the output filter capacitor, the controller IC, and the reference bypass capacitor. Keep the extra copper on the component and solder sides of the PC board rather than etching it away, and connect it to ground for use as a pseudo-ground plane. Refer to the MAX886/MAX888 evaluation kit for a two-layer PC board layout example.
Table 6. OUT0 and OUT4 Regulator Component Recommendations
fOSC (kHz) 925 670 535 375 C11 (F) 10 15 22 33 L1 (H) 10 15 22 33 C6 (F) 0.22 0.33 0.47 1 C12 (F) 10 15 22 33
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Wireless and Satellite Handset Power-Management ICs MAX886/MAX888
Pin Configuration
SYNC
TOP VIEW
CVH IN0 32 LX PGND OUT0 CVL REF GND BATT OUT4 1 2 3 4 5 6 7 8 9 C+ 10 IN4 31
ONSTAT
SDA
SCL
30
29
28
27
26
OFF 25 24 OUT1 23 IN1 22 OUT5 21 IN5 20 IN3 19 OUT3 18 OUT2 17 IN2 16 RESET
MAX886 MAX888
11 C-
12 DGND
13 LBI
14 LBHYS
15 LBO
ON
Chip Information
TRANSISTOR COUNT: 2042
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Wireless and Satellite Handset Power-Management ICs
Package Information
TQFPPO.EPS
MAX886/MAX888
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Wireless and Satellite Handset Power-Management ICs MAX886/MAX888
NOTES
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