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LTC1470/LTC1471 Single and Dual PCMCIA Protected 3.3V/5V VCC Switches
FEATURES
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DESCRIPTION
The LTC(R)1470 switches the VCC pins of a Personal Computer Memory Card International Association (PCMCIA) card slot between three operating states: OFF, 3.3V and 5V. Two low RDS(ON) N-channel power MOSFETs are driven by a built-in charge pump which generates a voltage higher than the supply voltage to fully enhance each switch when selected by the input control logic. The LTC1470 inputs are compatible with industry standard PCMCIA controllers. A built-in XOR ensures that both switches are never on at the same time. This function also makes the LTC1470 compatible with both active-low and active-high controllers (see Applications Information section). The switch rise times are controlled to eliminate power supply glitching. The LTC1470 features built-in SafeSlotTM current limit and thermal shutdown. The output is limited to 1A during short circuit to ground but 2A of peak operating current is allowed. The LTC1471 is a dual version of the LTC1470 and is available in a 16-pin SO package.
, LTC and LT are registered trademarks of Linear Technology Corporation. SafeSlot is a trademark of Linear Technology Corporation.
Single 3.3V/5V Switch in 8-Pin SO Package Dual 3.3V/5V Switch in 16-Pin SO Package Built-In Current Limit and Thermal Shutdown Built-In Charge Pumps (No 12V Required) Extremely Low RDS(ON) MOSFET Switches Output Current Capability: 1A Inrush Current Limited (Drives 150F Loads) Quiescent Current in Standby: 1A No Parasitic Body Diodes Built-In XOR Function Eliminates "Glue" Logic Break-Before-Make Switching Controlled Rise and Fall Times
APPLICATIONS
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Notebook Computers Palmtop Computers Pen-Based Computers Handi-Terminals PC Card Reader/Writers 3.3V/5V Power Supply Switch
TYPICAL APPLICATION
Dual Slot PCMCIA 3.3V/5V VCC Switch
5V 0.1F 5VIN 3VIN AOUT LTC1471 AEN1 PCMCIA CARD SLOT CONTROLLER AEN0 BEN1 (Hi-Z/3.3V/5V) BOUT VCC 10k
1470/71 TA01
Linear Technology PCMCIA Product Family
DEVICE DESCRIPTION Single PCMCIA VPP Driver/Regulator Dual PCMCIA VPP Driver/Regulator Single PCMCIA Switch Matrix Dual PCMCIA Switch Matrix Single Protected VCC 3.3V/5V Switch Matrix Dual Protected VCC 3.3V/5V Switch Matrix Protected VCC and VPP Switch Matrix PACKAGE 8-Pin SO 16-Pin SO* 14-Pin SO 24-Pin SSOP 8-Pin SO 16-Pin SO* 16-Pin SO*
3.3V 0.1F VCC (Hi-Z/3.3V/5V) VCC 10k VCC PCMCIA CARD SLOT PCMCIA CARD SLOT
LT (R)1312 LT1313 LTC1314 LTC1315 LTC1470 LTC1471 LTC1472
+
1F
BEN0 GND
+
1F
*Narrow Body
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LTC1470/LTC1471
ABSOLUTE MAXIMUM RATINGS
3.3V Supply Voltage (Note 1) .................................. 7V 5V Supply Voltage (Note1) ....................................... 7V Enable Input Voltage ........................ 7V to (GND - 0.3V) Output Voltage (OFF) (Note 1) ......... 7V to (GND - 0.3V) Output Short-Circuit Duration .......................... Indefinite Operating Temperature ............................... 0C to 70C Junction Temperature .......................................... 100C Storage Temperature Range ................ -65C to 150C Lead Temperature (Soldering, 10 sec)................. 300C
PACKAGE/ORDER INFORMATION
ORDER PART NUMBER
TOP VIEW OUT 1 5VIN 2 EN1 3 EN0 4 8 7 6 5 OUT 3VIN 3VIN GND
LTC1470CS8 S8 PART MARKING 1470
S8 PACKAGE 8-LEAD PLASTIC SO
TJMAX = 100C, JA = 150C/W
Consult factory for Industrial and Military grade parts.
ELECTRICAL CHARACTERISTICS
SYMBOL 3VIN 5VIN I3VIN PARAMETER 3.3V Supply Voltage Range 5V Supply Voltage Range 3.3V Supply Current
3VIN = 3.3V, 5VIN = 5V (Note 2), TA = 25C, unless otherwise noted.
MIN 2.70 4.75 TYP MAX 3.60 5.25 0.01 40 0.01 0.01 100 140 0.12 0.14
q
CONDITIONS
Program to Hi-Z (Note 3) Program to 3.3V, No Load (Note 3) Program to 5V, No Load (Note 3) Program to Hi-Z (Note 3) Program to 3.3V (Note 3) Program to 5V (Note 3) Program to 3.3V, IOUT = 500mA Program to 5V, IOUT = 500mA Program to Hi-Z, 0V VOUT 5V (Note 3) Program to 3.3V, VOUT = 0V (Note 4) Program to 5V, VOUT = 0V (Note 4)
I5VIN
5V Supply Current
RON ILKG ILIM3V ILIM5V VENH VENL IEN
3.3V Switch ON Resistance 5V Switch ON Resistance Output Leakage Current OFF 3.3V Current Limit 5V Current Limit Enable Input High Voltage Enable Input Low Voltage Enable Input Current
0V VEN 5V
2
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TOP VIEW AOUT 1 A5VIN 2 AEN1 3 AEN0 4 GND 5 B3VIN 6 B3VIN 7 BOUT 8 16 AOUT 15 A3VIN 14 A3VIN 13 GND 12 BEN0 11 BEN1 10 B5VIN 9 BOUT
ORDER PART NUMBER LTC1471CS
S PACKAGE 16-LEAD PLASTIC SO
TJMAX = 100C, JA = 100C/W
UNITS V V A A A A A A A A A V
q q q q q q
10 80 10 10 160 200 0.16 0.18 10
1 1
q q q
2.0 0.8 1
V A
LTC1470/LTC1471
ELECTRICAL CHARACTERISTICS
SYMBOL t0 to t3 t3 to t5 t0 to t5 PARAMETER Delay and Rise Time (Note 5) Delay and Rise Time (Note 5) Delay and Rise Time (Note 5)
3VIN = 3.3V, 5VIN = 5V (Note 2), TA = 25C, unless otherwise noted.
MIN 0.2 0.2 0.2 TYP 0.32 0.52 0.38 MAX 1.0 1.0 1.0 UNITS ms ms ms
CONDITIONS Transition from 0V to 3.3V, ROUT = 100, COUT = 1F Transition from 3.3V to 5V, ROUT = 100, COUT = 1F Transition from 0V to 5V, ROUT = 100, COUT = 1F
The q denotes the specifications which apply over the full operating temperature range. Note 1: For the LTC1470, the two output pins (1, 8) must be connected together and the two 3.3V supply input pins (6 , 7) must be connected together. For the LTC1471, the two AOUT pins (1, 16) must be connected together, the two BOUT pins (8, 9) must be connected together, the two A3VIN supply input pins (14, 15) must be connected together, the two B3VIN supply pins (6, 7) must be connected together and the two GND pins (5, 13) must be connected together.
Note 2: Power for the input logic and charge pump circuitry is derived from the 5VIN supply pin(s) which must be continuously powered. Note 3: Measured current is per channel with the other channel programmed off for the LTC1471. Note 4: The output is protected with foldback current limit which reduces the short-circuit (0V) currents below peak permissible current levels at higher output voltages. Note 5: To 90% of final value.
TYPICAL PERFORMANCE CHARACTERISTICS
3VIN Supply Current (OFF)
5 4 3 2 1 0 -1 0 TA = 25C PROGRAMMED TO OFF 120 100 80 60 40 20 0 4
1470/71 G04
3VIN SUPPLY CURRENT (A)
3VIN SUPPLY CURRENT (A)
5VIN SUPPLY CURRENT (A)
3 1 2 3VIN SUPPLY VOLTAGE (V)
5VIN Supply Current (3.3V ON)
300 250 200 150 100 50 0 TA = 25C PROGRAMMED TO 3.3V, NO LOAD
3.3V SWITCH RESISTANCE ()
5VIN SUPPLY CURRENT (A)
5VIN SUPPLY CURRENT (A)
0
1
2 3 4 5 5VIN SUPPLY VOLTAGE (V)
UW
6
1470/71 G03
(LTC1470 or 1/2 LTC1471) 5VIN Supply Current (OFF)
5 4 3 2 1 0 -1 TA = 25C PROGRAMMED TO OFF
3VIN Supply Current (3.3V ON)
TA = 25C PROGRAMMED TO 3.3V, NO LOAD
0
3 1 2 3VIN SUPPLY VOLTAGE (V)
4
1470/71 G05
0
1
2 3 4 5 5VIN SUPPLY VOLTAGE (V)
6
1470/71 G01
5VIN Supply Current (5V ON)
300 250 200 150 100 50 0 TA = 25C PROGRAMMED TO 5V, NO LOAD
0.30 0.25 0.20 0.15 0.10 0.05 0
3.3V Switch Resistance
PROGRAMMED TO 3.3V
0
1
5 2 3 4 5VIN SUPPLY VOLTAGE (V)
6
0
25 50 75 100 JUNCTION TEMPERATURE (C)
125
1470/71 G07
1470/71 G02
3
LTC1470/LTC1471
TYPICAL PERFORMANCE CHARACTERISTICS
5V Switch Resistance
OUTPUT VOLTAGE (V) INRUSH CURRENT (A)
OUTPUT VOLTAGE (V) INRUSH CURRENT (A)
0.30 0.25 0.20 0.15 0.10 0.05 0 0 25 50 75 100 JUNCTION TEMPERATURE (C) 125
1470/71 G06
PROGRAMMED TO 5V
5V SWITCH RESISTANCE ()
PIN FUNCTIONS
LTC1470
OUT (Pins 1, 8): Output Pins. The outputs of the LTC1470 are switched between three operating states: OFF, 3.3V and 5V. These pins are protected against accidental short circuits to ground by SafeSlot current limit circuitry which protects the socket, the card, and the system power supplies against damage. A second level of protection is provided by thermal shutdown circuitry which protects both switches against over-temperature conditions. 5VIN (Pin 2): 5V Input Supply Pin. The 5VIN supply pin serves two purposes. The first purpose is as the power supply input for the 5V NMOS switch. The second purpose is to provide power for the input, gate drive, and protection circuitry for both the 3.3V and 5V VCC switches. This pin must therefore be continuously powered. EN1, EN0 (Pins 3, 4): Enable Inputs. The two VCC Enable inputs are designed to interface directly with industry standard PCMCIA controllers and are high impedance CMOS gates with ESD protection diodes to ground, and should not be forced below ground. Both inputs have about 100mV of built-in hysteresis to ensure clean switching between operating modes. The LTC1470 is designed to operate without 12V power. The gates of the VCC NMOS switches are powered by charge pumps from the 5VIN supply pins (see Applications Information section for more detail). The Enable inputs should be turned off (both asserted high or both asserted low) at least 100s before the 5VIN power is removed to ensure that both VCC NMOS switch gates are fully discharged and both switches are in the high impedance mode. GND (Pin 5): Ground Connection. 3VIN (Pins 6, 7): 3V Input Supply Pins. The 3VIN supply pins serve as the power supply input for the 3.3V switches. These pins do not provide any power to the internal control circuitry and therefore do not consume any power when unloaded or turned off.
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(LTC1470 or 1/2 LTC1471) Inrush Current (5V Switch)
3 2 1 0 COUT = 150F ROUT = 10 6 4 2 0 - 0.2 0 0.2 0.4 0.6 0.8 TIME (ms) 1.0 1.2 1.4
1470/71 G08
Inrush Current (3.3V Switch)
3 2 1 0 COUT = 15F ROUT = 6.6 6 4 2 0 - 0.2 0 0.2 COUT = 150F ROUT = 6.6 0.4 0.6 0.8 TIME (ms) 1.0 1.2 1.4
1470/71 G09
TJ = 25C
COUT = 150F ROUT = 6.6
CURRENT LIMITED
TJ = 25C
COUT = 15F ROUT = 10
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LTC1470/LTC1471
PIN FUNCTIONS
LTC1471
AOUT, BOUT(Pins 1, 16, 8, 9): Output Pins. The outputs of the LTC1471 are switched between three operating states: OFF, 3.3V and 5V. These pins are protected against accidental short circuits to ground by SafeSlot current limit circuitry which protects the socket, the card, and the system power supplies against damage. A second level of protection is provided by thermal shutdown circuitry. 5VIN (Pins 2, 10): 5V Input Supply Pins. The 5VIN supply pins serve two purposes. The first purpose is as the power supply input for the 5V NMOS switches. The second purpose is to provide power for the input, gate drive, and protection circuitry. These pins must therefore be continuously powered. EN1, EN0 (Pins 3, 4, 11, 12): Enable Inputs. The enable inputs are designed to interface directly with industry standard PCMCIA controllers and are high impedance CMOS gates with ESD protection diodes to ground, and should not be forced below ground. All four inputs have about 100mV of built-in hysteresis to ensure clean switching between operating modes. The LTC1471 is designed to operate without 12V power. The gates of the VCC NMOS switches are powered by charge pumps from the 5VIN supply pins (see Applications Information section for more detail). The enable inputs should be turned off at least 100s before the 5VIN power is removed to ensure that all NMOS switch gates are fully discharged and are in the high impedance mode. GND (Pins 5, 13): Ground Connections. 3VIN (Pins 6, 7, 14, 15): 3V Input Supply Pins. The 3VIN supply pins serve as the power supply input for the 3.3V switches. These pins do not not provide any power to the internal control circuitry, and therefore, do not consume any power when unloaded or turned off.
BLOCK DIAGRAM
EN0
TTL-TO-CMOS CONVERTER
EN1
TTL-TO-CMOS CONVERTER
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(LTC1470 or 1/2 LTC1471)
5VIN GATE CHARGE AND DISCHARGE CONTROL LOGIC
0.14
BREAK-BEFOREMAKE SWITCH AND CONTROL
OSCILLATOR AND BIAS
CHARGE PUMP
CURRENT LIMIT AND THERMAL SHUTDOWN
OUTPUT
GATE CHARGE AND DISCHARGE CONTROL LOGIC
0.12
3VIN
LTC1470-BD01
5
LTC1470/LTC1471
OPERATION
The LTC1470 (or 1/2 of the LTC1471) consists of the following functional blocks: Input TTL/CMOS Converters The enable inputs are designed to accommodate a wide range of 3V and 5V logic families. The input threshold voltage is approximately 1.4V with approximately 100mV of hysteresis. The inputs enable the bias generator, the gate charge pumps and the protection circuity which are powered from the 5V supply. Therefore, when the inputs are turned off, the entire circuit is powered down and the 5V supply current drops below 1A. XOR Input Circuitry By employing an XOR function, which locks out the 3.3V switch when the 5V switch is turned on and locks out the 5V switch when the 3.3V switch is turned on, there is no danger of both switches being on at the same time. This XOR function also makes it possible to work with either active -low or active-high PCMCIA VCC switch control logic (see Applications Information section for further details). Break-Before-Make Switch Control Built-in delays are provided to ensure that the 3.3V and 5V switches are non-overlapping. Further, the gate charge pump includes circuitry which ramps the NMOS switches on slowly (400s typical rise time) but turns them off much more quickly (typically 10s). Bias, Oscillator and Gate Charge Pump When either the 3.3V or 5V switch is enabled, a bias current generator and high frequency oscillator are turned on. The on-chip capacitive charge pump generates approximately 12V of gate drive for the internal low RDS(ON) NMOS VCC switches from the 5VIN power supply. Therefore, an external 12V supply is not required to switch the VCC output. The 5VIN supply current drops below 1A when both switches are turned off. Gate Charge and Discharge Control All switches are designed to ramp on slowly (400s typical rise time). Turn-off time is much quicker (typically 10s). To ensure that both VCC NMOS switch gates are fully discharged, program the switch to the high impedance mode at least 100s before turning off the 5V power supply. Switch Protection Both switches are protected against accidental short circuits with SafeSlot foldback current limit circuits which limit the output current to typically 1A when the output is shorted to ground. Both switches also have thermal shutdown which limits the power dissipation to safe levels.
APPLICATIONS INFORMATION
The LTC1470/LTC1471 are designed to interface directly with industry standard PCMCIA card controllers. Interfacing with the CL-PD6710 Figure 1 is a schematic diagram showing the LTC1470 interfaced with a standard PCMCIA slot controller. The LTC1470 accepts logic control directly from the CL-PD6710. The XOR input function allows the LTC1470 to interface directly to the active-low VCC control outputs of the CLPD6710 for 3.3V/5V voltage selection (see the following Switch Truth Table). Therefore, no "glue" logic is required to interface to this PCMCIA compatible card controller.
3.3V 0.1F 3VIN 5V 0.1F CL-PD6710 VCC _3 VCC _5 LTC1470 EN0 EN1 GND OUT OUT (OFF/3.3V/5V) 5VIN 3VIN
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1F TANT
TO CARD VCC PINS
10k
1470/71 F01
Figure 1. Direct Interface to CL-PD6710 PCMCIA Controller
LTC1470/LTC1471
APPLICATIONS INFORMATION
Truth Table for CL-PD6710 Controller
A_VCC _3 EN0 0 0 1 1 A_VCC _5 EN1 0 1 0 1 OUT Hi-Z 3.3V 5V Hi-Z
Interfacing with "365" Type Controllers The LTC1470 also interfaces directly with "365" type controllers as shown in Figure 2. Note that the VCC Enable inputs are connected differently than to the CL-PD6710 controller because the "365" type controllers use activehigh logic control of the VCC switches (see the following Switch Truth Table). No "glue" logic is required to interface to this type of PCMCIA compatible controller.
3.3V 0.1F 3VIN 5V 0.1F "365" TYPE CONTROLLER A_VCC _EN0 A_VCC _EN1 LTC1470 EN0 EN1 GND OUT OUT (OFF/3.3V/5V) 5VIN 3VIN
+
1F TANT
10k
1470/71 F02
Figure 2. Direct Interface with "365" Type PCMCIA Controller Truth Table for "365" Type Controller
A_VCC _EN0 EN0 0 0 1 1 A_VCC_EN1 EN1 0 1 0 1 OUT Hi-Z 3.3V 5V Hi-Z
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Supply Bypassing For best results bypass the supply input pins with 1F capacitors as close as possible to the LTC1470. Sometimes much larger capacitors are already available at the outputs of the 3.3V and 5V power supply. In this case it is still good practice to use 0.1F capacitors as close as possible to the device, especially if the power supply output capacitors are more than 2" away on the printed circuit board. Output Capacitors and Pull-Down Resistor The output pin is designed to ramp on slowly, typically 400s rise time. Therefore, capacitors as large as 150F can be driven without producing voltage spikes on the 3VIN or 5VIN supply pins (see graphs in Typical Performance Characteristics section). The output pin should have a 0.1F to 1F capacitor for noise reduction and smoothing. A 10k pull-down resistor is recommended at the output to ensure that the output capacitor is fully discharged when the output is switched OFF. This resistor also ensures that the output is discharged between the 3.3V and 5V transition. Supply Sequencing
TO CARD VCC PINS
Because the 5V supply is the source of power for both of the switch control circuits, it is best to sequence the power supplies such that the 5V supply is powered before, or simultaneous to, the application of 3.3V. It is interesting to note, however, that the switches are NMOS transistors which require charge pumps to generate gate voltages higher than the supply rails for full enhancement. Because the gate voltages start at 0V when the supplies are first activated, the switches always start in the off state and do not produce glitches at the outputs when powered. If the 5V supply must be turned off, it is important to program all switches to the Hi-Z or 0V state at least 100s before the 5V power is removed to ensure that the NMOS switch gates are fully discharged to 0V. Whenever possible, however, it is best to leave the 5VIN pin(s) continuously powered. The LTC1470/LTC1471 quiescent current drops to <1A with all the switches turned off and therefore no 5V power is consumed in the standby mode.
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LTC1470/LTC1471
APPLICATIONS INFORMATION
TOTAL SYSTEM COST CONSIDERATIONS The cost of an additional step-up switching regulator, inductor, rectifier and capacitors to produce 12V for VPP can be eliminated by using an auxiliary winding on either the 3.3V or 5V output of the system switching regulator to produce an auxiliary 15V supply for VPP power. And, because the LTC1470/LTC1471 do not require 12V power to operate (only 5V), the 12V VPP regulation and switching may be operated separately from the 3.3V/5V VCC switching. This increases system configuration flexibility and reduces total system cost by eliminating the need for a third regulator for 12V power.
VIN 6.5V TO 18V VIN 10 D1 MBRS140
+
9 Q1
C1 68F
PDRIVE
1/2 LTC1142HV (5V REG)
NDRIVE
20
Q2
SENSE +
15 C2 1000pF
D3 MBRS130T3 T1* R1 30H 100
SENSE -
14 R3 18k
R2 100
R5 0.033
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Q3 2N7002 AVPPEN0 BVPPEN0
Q4 2N7002 3.3V 0.1F A3VIN A3VIN B3VIN B3VIN
* LPE-6562-A026 DALE (605) 665-9301
Figure 3. Cost Effective Complete SafeSlot Dual PCMCIA Power Management System (with 15V Auxiliary Supply from LTC1142HV 5V Regulator Inductor)
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LTC1142HV Auxiliary Winding Power Supply Figure 3 is a schematic diagram which describes how a loosely regulated 15V power supply is created by adding an auxiliary winding to the 5V inductor in a split 3.3V/5V LTC1142HV power supply system. An LT1313, dual VPP regulator/driver with SafeSlot protection, produces "clean" 3.3V, 5V and 12V power from this loosely regulated 15V output for the PC card slot VPP pins. (See LT1312 and LT1313 data sheets for further detail.) A turns ratio of 1:1.8 is used for transformer T1 to ensure that the input voltage to the LT1313 falls between 13V and 20V under all load conditions. The 9V output from this additional
(15V)
R4 22
C4 1000pF AVPPEN0 AVPPEN1 D2 MBRS140 AVALID
VS AEN0 AEN1 AVALID
VS AVPPOUT
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1F
TO "A" SLOT VPP PINS
1.8:1
+
LT1313 C5 22F BVPPEN0 BVPPEN1 5V OUTPUT BVALID BEN0 BEN1 BVALID BSENSE GND ASENSE BVPPOUT FROM "A" VCC PINS
+
1F
TO "B" SLOT VPP PINS
C3 220F
FROM "B" VCC PINS
GND
5V 0.1F
A5VIN B5VIN LTC1471 AVCCEN0 AVCCEN1 BVCCEN0 BVCCEN1 AEN0 AEN1 BEN0 BEN1 GND GND
BOUT BOUT
+
1F TANT
TO "A" SLOT VCC PINS 10k
AOUT AOUT
+
1F TANT
10k
TO "B" SLOT VCC PINS
1470/71 F03
LTC1470/LTC1471
APPLICATIONS INFORMATION
winding is rectified by diode D2, added to the main 5V output and applied to the input of the LT1313. (Note that the auxiliary winding must be phased properly as shown in Figure 3.) When the 12V output is activated by a TTL high on either VPP enable lines, the 5V section of the LTC1142HV is forced into continuous mode operation. A resistor divider composed of R2, R3 and switch Q3 forces an offset which is subtracted from the internal offset at the Sense- input (pin 14) of the LTC1142HV. When this external offset cancels the built-in 25mV offset, Burst ModeTM operation is inhibited and the LTC1142HV is forced into continuous mode operation. (See LTC1142HV data sheet for further detail.) In this mode, the 15V auxiliary supply can be loaded without regard to the loading on the 5V output of the LTC1142HV. Continuous mode operation is only invoked when the LT1313 is programmed to 12V. If the LT1313 is programmed to 0V, 3.3V or 5V, power is obtained directly from the main power source (battery pack) through diode D1. Again, the LT1313 output can be loaded without regard to the loading of the main 5V output.
VIN 5.4V TO 11V VIN 24
PDRIVE
23
Q1
1/2 LTC1142 (3.3V REG)
NDRIVE
6
Q2
1 SENSE + C2 1000pF SENSE - 28 R3 12k HC86 AENVPP0 AENVPP1 HC86 BENVPP0 BENVPP1 Q3 2N7002
Figure 4. Deriving 15V from the 3.3V Output of the LTC1142 for VPP Power
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R4 and C4 absorb transient voltage spikes associated with the leakage inductance inherent in T1's secondary winding and ensure that the auxiliary supply does not exceed 20V. Auxiliary Power from the LTC1142 3.3V Output For low-battery count applications (< 6.5V) it is necessary to modify the circuit of Figure 3. As the input voltage falls, the 5V duty cycle increases to the point where there is simply not enough time to transfer energy from the 5V primary winding to the auxiliary winding. For applications where 12V load currents exist in conjunction with these low input voltages, use the circuit shown in Figure 4. In this circuit, the auxiliary 15V supply is generated from an overwinding on the 3.3V inductor of the LTC1142 regulator output. In Figure 3, power is drawn directly from the batteries through D1 when the regulator is in Burst Mode operation and the VPP pins require 3.3V or 5V. In this circuit, however, Q3 and Q4 force the LTC1142 3.3V regulator into continuous mode operation whenever 3.3V, 5V or 12V is programmed at the VPPOUT pins of the LT1313. (See the LT1312 and LT1313 data sheets for further detail.)
Burst Mode is a trademark of Linear Technology Corporation.
+
C1 68F D2 MBRS1100 15V AUX SUPPLY D3 MBRS130T3 T1* 15H R1 100 R4 0.033 3.37:1 D4 18V
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C5 68F
R2 100
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3.3V OUTPUT C3 220F
Q4 2N7002 *CTX02-12753 COILTRONICS (407) 241-7876
1470/71 F04
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LTC1470/LTC1471
TYPICAL APPLICATIONS
Dual Slot 3.3V/5V PCMCIA Controller with SafeSlot Current Limit (Systems with No 12V Power Requirements)
3.3V 0.1F A3VIN A3VIN B3VIN B3VIN 5V 0.1F CL-PD6710 A_VCC _3 A_VCC _5 B_VCC _3 B_VCC _5 AEN0 AEN1 BEN0 BEN1 GND GND AOUT (OFF/3.3V/5V) AOUT VCC VCC PCMCIA CARD SLOT A5VIN B5VIN LTC1471 BOUT (OFF/3.3V/5V) BOUT VCC VCC PCMCIA CARD SLOT
Single Slot PCMCIA Controller with SafeSlot Current Limit Protection Using LT1312 Single VPP Regulator/Driver
VLOGIC 13V TO 20V* VCC VPP_PGM VPP_VCC VPP_VALID 51k EN0 EN1 VALID GND VS VPPOUT LT1312 SENSE VPP1
CIRRUS LOGIC CL-PD6710
VCC _5 VCC _3
* FROM OVERWINDING ON 3.3V OR 5V INDUCTOR IN SYSTEM POWER SUPPLY. SEE FIGURES 3, 4 FOR FURTHER DETAIL
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1F TANT
10k
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1F TANT
10k
1470/71 TA02
+
1F
VPP2 VCC
PCMCIA CARD SLOT
3.3V 0.1F 3VIN 5VIN 0.1F LTC1470 EN0 EN1 GND 0UT 0UT 3VIN 10k
5V
+
1F TANT
1470/71 TA03
LTC1470/LTC1471
TYPICAL APPLICATIONS
Dual Slot PCMCIA Controller with SafeSlot Current Limit Protection Using LT1313 Dual VPP Regulator/Driver
VLOGIC
A_VPP_PGM A_VPP_VCC
B_VPP_PGM B_VPP_VCC VPP_VALID
CL-PD6720 3.3V 0.1F A3VIN A3VIN B3VIN B3VIN 5V 0.1F A5VIN B5VIN LTC1471 A_VCC _3V A_VCC _5V B_VCC _3V B_VCC _5V AEN0 AEN1 BEN0 BEN1 GND GND AOUT (OFF/3.3V/5V) AOUT BOUT (OFF/3.3V/5V) BOUT
* FROM OVERWINDING ON 3.3V OR 5V INDUCTOR IN SYSTEM POWER SUPPLY. SEE FIGURES 3, 4 FOR FURTHER DETAILS
Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of circuits as described herein will not infringe on existing patent rights.
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13V TO 20V* 0.1F 51k AEN0 AEN1 AVALID LT1313 BEN0 BEN1 BVALID GND BSENSE GND BVPPOUT ASENSE AVS BVS AVPPOUT VPP1 VPP2
+
1F VCC VPP1 VPP2
PCMCIA CARD SLOT #1
+
1F VCC
PCMCIA CARD SLOT #2
+
1F TANT
10k
+
1F TANT
10k
1470/71 TA04
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LTC1470/LTC1471
PACKAGE DESCRIPTION
0.010 - 0.020 x 45 (0.254 - 0.508) 0.008 - 0.010 (0.203 - 0.254) 0- 8 TYP
0.016 - 0.050 0.406 - 1.270
*THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.006 INCH (0.15mm).
0.010 - 0.020 x 45 (0.254 - 0.508) 0.008 - 0.010 (0.203 - 0.254) 0 - 8 TYP
0.016 - 0.050 0.406 - 1.270
*THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.006 INCH (0.15mm).
RELATED PARTS
See PCMCIA Product Family table on the first page of this data.
12
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7487
(408) 432-1900 q FAX: (408) 434-0507 q TELEX: 499-3977
U
Dimensions in inches (millimeters) unless otherwise noted. S8 Package 8-Lead Plastic SOIC
0.189 - 0.197* (4.801 - 5.004) 8 7 6 5
0.053 - 0.069 (1.346 - 1.752)
0.004 - 0.010 (0.101 - 0.254) 0.228 - 0.244 (5.791 - 6.197) 0.150 - 0.157* (3.810 - 3.988)
0.014 - 0.019 (0.355 - 0.483)
0.050 (1.270) BSC
1
2
3
4
SO8 0294
S Package 16-Lead Plastic SOIC
0.386 - 0.394* (9.804 - 10.008) 16 15 14 13 12 11 10 9
0.228 - 0.244 (5.791 - 6.197)
0.150 - 0.157* (3.810 - 3.988)
1 0.053 - 0.069 (1.346 - 1.752)
2
3
4
5
6
7
8
0.004 - 0.010 (0.101 - 0.254)
0.014 - 0.019 (0.355 - 0.483)
0.050 (1.270) TYP
SO16 0893
LT/GP 0495 10K * PRINTED IN USA
(c) LINEAR TECHNOLOGY CORPORATION 1995

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