LTC1472 Protected PCMCIA VCC and VPP Switching Matrix U FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ DESCRIPTION Both VCC and VPP Switching in a Single Package Built-In Current Limit and Thermal Shutdown 16-Pin (Narrow) SOIC Package Inrush Current Limited (Drives 150µF Loads) Continuous 12V Power Not Required Extremely Low RDS(ON) NMOS Switches Guaranteed 1A VCC Current and 120mA VPP Current 1µA Quiescent Current in Standby No External Components Required Compatible with Industry Standard Controllers Break-Before-Make Switching Controlled Rise and Fall Times U APPLICATIONS ■ ■ ■ ■ ■ The LTC®1472 switching matrix routes power to both the VCC and VPP power supply pins of the PCMCIA compatible card socket. The VCC output of the LTC1472 is switched between three operating states: OFF, 3.3V, and 5V. The VPP output is switched between four operating states: 0V, VCC, 12V, and Hi-Z. The output voltages are selected by two sets of digital inputs which are compatible with industry standard PC Card controllers (see Truth Tables). The VCC output of the LTC1472 can supply up to 1A of current and the VPP output up to 120mA. Both switches have built-in SafeSlotTM current limiting and thermal shutdown to protect the card, socket and power supply against accidental short-circuit conditions. The LTC1472 is designed to conserve power by automatically dropping to 1µA standby current when the two outputs are switched OFF. A shutdown pin is provided which holds the external 12V regulator in standby mode except when required for VPP power. Notebook Computers Palmtop Computers Pen-Based Computers Handi-Terminals Bar-Code Readers The LTC1472 is available in 16-pin SO. , LTC and LT are registered trademarks of Linear Technology Corporation. SafeSlot is a trademark of Linear Technology Corporation. U TYPICAL APPLICATION Linear Technology PCMCIA Product Family Protected PCMCIA VCC and VPP Card Driver 12V 3.3V 3VIN VPPIN SHDN 5VIN 5V DEVICE 0.1µF 0.1µF 0.1µF VPPOUT LTC1472 ® VDD PCMCIA CARD SLOT CONTROLLER Single PCMCIA VPP Driver/Regulator 8-Pin SO LT1313 Dual PCMCIA VPP Driver/Regulator 16-Pin SO* VPP1 LTC1314 Single PCMCIA Switch Matrix 14-Pin SO VPP2 LTC1315 Dual PCMCIA Switch Matrix 24-Pin SSOP LTC1470 Protected VCC 5V/3.3V Switch Matrix 8-Pin SO VCC LTC1471 Dual Protected VCC 5V/3.3V Switch Matrix 16-Pin SO* VCC LTC1472 Protected VCC and VPP Switch Matrix 16-Pin SO* PCMCIA CARD SLOT VPP EN0 VPP EN1 VCC(IN) VCC EN0 VCC(OUT) VCC EN1 GND OFF, 3.3V, 5V + 10k 1µF PACKAGE LT 1312 TO 12V REGULATOR OV, VCC, 12V, Hi-Z 0.1µF DESCRIPTION LTC1472-TA01 *Narrow Body 1 LTC1472 W U U W W W 5VIN Supply Voltage ................................... – 0.3V to 7V 3VIN Supply Voltage ................................... – 0.3V to 7V VPPIN Supply Voltage ............................ – 0.3V to 13.2V VCC(IN) Supply Voltage ................................... – 0.3 to 7V VDD(IN) Supply Voltage ............................... – 0.3V to 7V VPPOUT (OFF) ........................................ – 0.3V to 13.2V VCC(OUT) (OFF) ............................................ – 0.3V to 7V Enable Inputs .............................................. – 0.3V to 7V VPPOUT Short-Circuit Duration ........................ Indefinite VCC(OUT) Short-Circuit Duration ....................... Indefinite Operating Temperature Range ..................... 0°C to 70°C Junction Temperature........................................... 100°C Storage Temperature Range ................. – 65°C to 150°C Lead Temperature (Soldering, 10 sec).................. 300°C U ABSOLUTE MAXIMUM RATINGS PACKAGE/ORDER INFORMATION ORDER PART NUMBER TOP VIEW VCC(OUT) 1 16 VCC(OUT) 5VIN 2 15 3VIN VCC EN1 3 14 3VIN VCC EN0 4 13 GND VPPIN 5 12 VCC(IN) SHDN 6 11 VPPOUT VPP EN0 7 10 GND VPP EN1 8 9 LTC1472CS VDD S PACKAGE 16-LEAD PLASTIC SO TJMAX = 100°C, θJA = 100°C/W Consult factory for Industrial and Military grade parts. ELECTRICAL CHARACTERISTICS (VCC Switch Section) 5VIN = 5V, 3VIN = 3.3V, VPP EN0 = VPP EN1 = OV, TA = 25°C, (Note 1) unless otherwise noted. SYMBOL PARAMETER CONDITIONS MIN 5VIN 5VIN Supply Voltage Range (Note 2) 4.75 3VIN 3VIN Supply Voltage Range (Note 3) 3.60 V I5VIN 5VIN Supply Current Program to Hi-Z Program to 5V, No Load Program to 3.3V, No Load ● ● ● 0.01 140 100 10 200 160 µA µA µA I3VIN 3VIN Supply Current Program to Hi-Z. Program to 5V, No Load Program to 3.3V, No Load ● ● ● 0.01 0.01 40 10 10 80 µA µA µA RON 5V Switch On Resistance 3.3V Switch On Resistance Program to 5V, IOUT = 500mA Program to 3.3V, IOUT = 500mA 0.14 0.12 0.18 0.16 Ω Ω ILKG Output Leakage Current OFF VCC EN0 = VCC EN1 = 0V or 5V, 0V ≤ VCC(OUT) ≤ 5V ±10 µA ILIM5V VCC(OUT) 5V Current Limit Program to 5V, VCC(OUT) = 0V (Note 4) 1 A ILIM3V VCC(OUT) 3.3V Current Limit Program to 3.3V, VCC(OUT) = 0V (Note 4) 1 A VCCENH VCC Enable Input High Voltage VCCENL VCC Enable Input Low Voltage IVCCEN VCC Enable Input Current 0V ≤ VCCEN ≤ 5V tVCC1 Delay + Rise Time From 0V to 3.3V, RLOAD = 100Ω, CLOAD = 1µF (Note 5) tVCC2 Delay + Rise Time From 3.3V to 5V, RLOAD = 100Ω, CLOAD = 1µF (Note 5) 0.2 0.52 1 ms tVCC3 Delay + Rise Time From 0V to 5V, RLOAD = 100Ω, CLOAD = 1µF (Note 5) 0.2 0.38 1 ms 2 TYP 0 ● ● MAX UNITS 5.25 V 2 V ● 0.8 V ● ±1 µA 1 ms 0.2 0.32 LTC1472 ELECTRICAL CHARACTERISTICS (VPP Switch Section) VDD = 5V, VCC(IN) = 5V, VPPIN = 12V, VCCEN0 = VCCEN1 = 0V, TA= 25°C, (Note 1), unless otherwise noted. SYMBOL PARAMETER CONDITIONS MIN MAX UNITS VCC(IN) VCC Input Voltage Range 3 5.5 V VPPIN VPP Input Voltage Range (Note 6) VDD Logic Supply Voltage Range (Note 7) ● 0 12.6 V ● 4.5 5.5 V ICCIN VCC(IN) Supply Current, No Load Program to VPPIN or VCC(IN) VPPIN = 12V Program to 0V or Hi-Z ● ● 35 0.01 60 10 µA µA IPPIN VPPIN Supply Current, No Load Program to VPPIN or VCC(IN) Program to 0V or Hi-Z ● ● 40 0.01 80 10 µA µA IDD VDD Supply Current, No Load Program to VPPIN Program to VCC(IN), VPPIN = 0V Program to VCC(IN), VPPIN = 12V Program to 0V or Hi-Z ● ● ● ● 70 85 40 0.01 120 150 80 10 µA µA µA µA IVPPOUT RON Hi-Z Output Leakage Current Program to Hi-Z, 0V < VPPOUT < 12V ● 0.01 10 µA On Resistance VPPOUT to VPPIN On Resistance VPPOUT to VCC(IN) On Resistance VPPOUT to GND VPPIN = 12V, ILOAD = 120mA VCC(IN) = 5V, ILOAD = 5mA VDD = 5V, ISINK = 1mA 0.50 1.70 100 1 5 250 Ω Ω Ω VPPENH VPP Enable Input High Voltage VDD = 5V ● VPPENL VPP Enable Input Low Voltage VDD = 5V ● 0.8 V IVPPEN VPP Enable Input Current 0V < VPP EN < VDD ● ±1 µA VSDH SHDN Output High Voltage Program to 0V, VCC(IN) or Hi-Z, ILOAD = 400µA ● VSDL SHDN Output Low Voltage Program to VPPIN, ISINK = 400µA ● ILIMVCC VPPOUT Current Limit, VCC(IN) Program to VCC(IN), VPPOUT = 0V (Note 4) ILIMVPP VPPOUT Current Limit, VPPIN Program to VPPIN, VPPOUT = 0V (Note 4) tVPP1 Delay and Rise Time From 0V to VCC(IN),VPPIN = 0V (Note 8) 5 15 50 µs tVPP2 Delay and Rise Time From 0V to VPPIN (Note 8) 25 85 250 µs tVPP3 Delay and Rise Time From VCC(IN) to VPPIN (Note 8) 30 100 300 µs tVPP4 Delay and Fall Time From VPPIN to VCC(IN) (Note 9) 5 15 50 µs tVPP5 Delay and Fall Time From VPPIN to 0V (Note 10) 10 35 100 µs tVPP6 Delay and Fall Time From VCC(IN) to 0V, VPPIN = 0V (Note 10) 10 30 100 µs tVPP7 Output Turn-On Delay From Hi-Z to VCC(IN) (Note 8) 5 15 50 µs tVPP8 Output Turn-On Delay From Hi-Z to VPPIN (Note 8) 25 85 250 µs ● The ● denotes the specifications which apply over the full operating temperature range. Note 1: VENH = 5V, VENL = 0V. See VCC and VPP Switch Truth Tables for programming enable inputs for desired output states. Note 2: Power for the VCC input logic and charge pump circuitry is derived from the 5VIN power supply which must be continuously powered. 12V and 3.3V power is not required to control the NMOS VCC switches. (See Applications Information.) Note 3: The two 3VIN supply input pins (14 and 15) must be connected together and the two VCC(OUT) output pins (1 and 16) must be connected together. The 3VIN supply pins do not need to be continuously powered and may drop to 0V when not required. Note 4: The VCC and VPP output are protected with foldback current limit which reduces the short-circuit (0V) currents below peak permissible current levels at higher output voltages. TYP 2 V 3.5 V 0.4 60 V mA 100 mA Note 5: To 90% of final value. Note 6: 12V power is only required when VPPOUT is programmed to 12V. The external 12V regulator can be shutdown at all other times. Built-in charge pumps power the internal NMOS switches from the 5V VDD supply when 12V is not present. Note 7: Power for the VPP input logic and charge pump circuitry is derived from the VDD power supply which must be continuously powered. Note 8: To 90% of the final value, COUT = 0.1µF, ROUT = 2.9k. Note 9: To 10% of the final value, COUT = 0.1µF, ROUT = 2.9k. Note 10: To 50% of the initial value, COUT = 0.1µF, ROUT = 2.9k. 3 LTC1472 U W TYPICAL PERFORMANCE CHARACTERISTICS 5VIN Supply Current (5V ON) 5VIN Supply Current (OFF) 2 1 250 5VIN SUPPLY CURRENT (µA) 3 300 TA = 25°C VCC(OUT) PROGRAMMED TO 5V, NO LOAD 200 150 100 50 0 0 1 5 2 3 4 5VIN SUPPLY VOLTAGE (V) 6 0 1 5 2 3 4 5VIN SUPPLY VOLTAGE (V) 2 1 TA = 25°C VCC(OUT) PROGRAMMED TO 3.3V, NO LOAD 80 60 40 0.20 0.15 0.10 0 4 OUTPUT VOLTAGE (V) INRUSH CURRENT (A) 0.15 0.10 0.05 0 25 50 75 100 JUNCTION TEMPERATURE (°C) 125 LT1472 TPC07 Inrush Current (3.3V Switch) 3 2 TJ = 25°C CURRENT LIMITED 1 0 6 COUT = 150µF ROUT = 10Ω COUT = 15µF ROUT = 10Ω 4 2 0 – 0.2 0 0.2 0.4 0.6 0.8 TIME (ms) 125 25 50 75 100 JUNCTION TEMPERATURE (°C) LT1472 TPC06 Inrush Current (5V Switch) 0.20 0 0.25 LTC1472 TPC05 LTC1472 TPC04 VCC(OUT) PROGRAMMED TO 3.3V VCC(OUT) PROGRAMMED TO 5V 0 3 1 2 3VIN SUPPLY VOLTAGE (V) 0 3.3V Switch Resistance 6 0.05 0 4 0.30 5 2 3 4 5VIN SUPPLY VOLTAGE (V) 5V Switch Resistance 20 3 1 2 3VIN SUPPLY VOLTAGE (V) 1 LTC1472 TPC03 5V SWITCH RESISTANCE (Ω) 3VIN SUPPLY CURRENT (µA) 3VIN SUPPLY CURRENT (µA) 3 0 0.30 100 0 3.3V SWITCH RESISTANCE (Ω) 0 6 120 TA = 25°C OUTPUT PROGRAMMED TO OFF 0.25 100 3VIN Supply Current (3.3V ON) 5 0 150 LTC1472 TPC02 3VIN Supply Current (OFF) –1 200 50 LTC1472 TPC01 4 TA = 25°C VCC(OUT) PROGRAMMED TO 3.3V, NO LOAD 250 1.0 1.2 1.4 LTC1472 TPC08 OUTPUT VOLTAGE (V) INRUSH CURRENT (A) 4 5VIN SUPPLY CURRENT (µA) 5VIN SUPPLY CURRENT (µA) TA = 25°C VCC(OUT) PROGRAMMED TO OFF 0 4 5VIN Supply Current (3.3V ON) 300 5 –1 (VCC Section) VPP EN0 = VPP EN1 = 0V 3 TJ = 25°C 2 COUT = 150µF ROUT = 6.6Ω 1 0 6 COUT = 15µF ROUT = 6.6Ω 4 COUT = 150µF ROUT = 6.6Ω 2 0 – 0.2 0 0.2 0.4 0.6 0.8 TIME (ms) 1.0 1.2 1.4 LTC1472 TPC09 LTC1472 U W TYPICAL PERFORMANCE CHARACTERISTICS (VPP Section) VCC EN0 = VCC EN1 = 0V VCC(IN) Supply Current (No Load) VPPIN Supply Current (OFF) 100 60 VPPOUT PROGRAMMED TO VPPIN OR VCC(IN) 40 20 0 VPPOUT PROGRAMMED TO 0V OR Hi-Z 0 1 TA = 25°C VPPOUT PROGRAMMED TO 0V OR Hi-Z 4 3 2 1 0 –1 5 3 4 VCC(IN) SUPPLY VOLTAGE (V) 2 0 6 8 6 10 4 VPPIN SUPPLY VOLTAGE 2 VDD Supply Current (OFF) 1 TA = 25°C VPPOUT PROGRAMMED TO VPPIN, NO LOAD 8 6 10 4 VPPIN SUPPLY VOLTAGE 2 60 40 6 12 14 LTC1472 TPC12 TA = 25°C VPPOUT PROGRAMMED TO VPPIN, NO LOAD 100 80 0 2 3 4 5 VDD SUPPLY VOLTAGE (V) VPPOUT PROGRAMMED TO VCC(IN) 20 VDD Supply Current (ON) 20 0 80 VPPIN = 0V 60 40 VPPIN = 12V 20 0 1 5 2 3 4 VDD SUPPLY VOLTAGE (V) 6 LTC1472 TPC14 LTC1472 TPC13 0 0 1 2 3 4 5 VDD SUPPLY VOLTAGE (V) 6 LTC1472 TPC15 Switch Resistances 10 SWITCH RESISTANCE (Ω) 1 40 0 VDD SUPPLY CURRENT (µA) VDD SUPPLY CURRENT (µA) 2 VPPOUT PROGRAMMED TO VPPIN 60 120 100 3 0 80 VDD Supply Current (No Load) TA = 25°C VPPOUT PROGRAMMED TO 0V OR Hi-Z 4 100 0 14 120 5 VDD SUPPLY CURRENT (µA) 12 TA = 25°C VPPIN = 12V NO LOAD LTC1472 TPC11 LTC1472 TPC10 –1 VPPIN SUPPLY CURRENT (µA) 80 VPPIN SUPPLY CURRENT (µA) VCC(IN) SUPPLY CURRENT (µA) TA = 25°C –20 VPPIN Supply Current (No Load) 120 5 VCCIN TO VPPOUT 1 VPPIN TO VPPOUT 0.1 0 20 40 60 TEMPERATURE (°C) 80 100 LTC1472 TPC16 5 LTC1472 U U U PIN FUNCTIONS Enable Input (Pins 3,4,7,8) VCC(IN) Supply (Pin 12) The two VCC and two VPP Enable inputs are designed to interface directly with industry standard PCMCIA controllers. They are high impedance CMOS gates with ESD protection diodes to ground, and should not be forced below ground. Both sets of inputs have about 100mV of built-in hysteresis to ensure clean switching between operating modes. The VCC(IN) supply pin is typically connected directly to the VCC(OUT) pin from the VCC switch section of the LTC1472. It can also be connected directly to a 3.3V or 5V power supply if desired. This supply pin does not provide any power to the internal control circuitry and is simply the input to the VCC(IN)-VPPOUT switch and therefore does not consume any power when unloaded or turned off. Shutdown Output (Pin 6) 5VIN Supply (Pin 2) The LTC1472 is designed to operate without continuous 12V power. The gates of the VCC NMOS switches are powered by charge pumps from the 5VIN supply, and the gates of the VPP NMOS switches are powered by charge pumps powered from the VDD supply when 12V is not present at the VPPIN pin (see Application Information for more details). Therefore, the external 12V regulator can be shut down most of the time, and only turned on when programming the socket VPP pin to 12V. 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 be continuously powered. The shutdown output is active high; i.e. the system 12V regulator is shut down when this output is held high and turned on when this output is held low. VPPIN Supply (Pin 5) The VPPIN supply pin serves two purposes. The first purpose is to provide power and gate drive for the VPPINVPPOUT switch. The second purpose is to provide optional 12V gate drive for the VCC(IN)-VPPOUT switch. If, however, this 12V power is not available, gate drive is obtained automatically from the 5V VDD supply by an internal 5V to 12V charge pump converter. VDD Supply (Pin 9) The VDD pin provides power for the input, charge pump and control circuitry for the VPP section of the LTC1472 and therefore must be continuously powered. The standby quiescent current is typically 0.1µA when the VPPOUT pin is programmed to 0V or Hi-Z and only rises to micropower levels when the VPP switches are active. 6 The enable inputs should be turned off (both asserted high or both asserted low) at least 100µs 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. 3VIN Supply (Pins 14,15) The 3VIN supply pin serves as the power supply input for the 3.3V switch. This pin does not provide any power to the internal control circuitry and therefore does not consume any power when unloaded or turned off. VCC(OUT) and VPPOUT Output (Pins 1,11,16) The VCC output of the LTC1472 is switched between the three operating states: OFF, 3.3V, and 5V. The VPP output is switched between four operating states: 0, VCC, 12V and Hi-Z. Both pins are protected against accidental shortcircuit conditions to ground by independent SafeSlot foldback current-limit circuitry which protects the socket, card and the system power supplies against damage. A second level of protection is provided by independent thermal shut down circuitry which protects each switch against overtemperature conditions. LTC1472 W BLOCK DIAGRAM 5VIN GATE CHARGE AND DISCHARGE CONTROL LOGIC VCC EN0 VCC EN1 TTL-TO-CMOS CONVERTER BREAK-BEFOREMAKE SWITCH AND CONTROL OSCILLATOR AND BIAS TTL-TO-CMOS CONVERTER CHARGE PUMP 0.14Ω CURRENT LIMIT AND THERMAL SHUTDOWN GATE CHARGE AND DISCHARGE CONTROL LOGIC VCC(OUT) 0.12Ω 3VIN VDD VPPIN SHDN VPP EN0 TTL-TO-CMOS CONVERTER BREAK-BEFOREMAKE SWITCH VPP EN1 TTL-TO-CMOS CONVERTER GATE CHARGE AND DISCHARGE CONTROL LOGIC OSCILLATOR AND BIAS CHARGE PUMP 0.5Ω CURRENT LIMIT AND THERMAL SHUTDOWN VCC(IN) VPPIN + 10V GATE CHARGE AND DISCHARGE CONTROL LOGIC CHARGE PUMP 1.7Ω – VPPOUT 100Ω LTC1470-BD01 U OPERATION The LTC1472 protected switch matrix is designed to be a complete single slot solution for VCC and VPP switching in a PCMCIA compatible card system. The LTC1472 consists of two independent functional sections: the VCC switching section, and the VPP switching section. THE VCC SWITCHING SECTION The VCC switching section of the LTC1472 consist of the following functional blocks: VCC Switch Input TTL-CMOS Converters The LTC1472 VCC 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 5VIN supply. Therefore, when the inputs are turned off, the entire circuit is powered down and the 5VIN supply current drops below 1µA. 7 LTC1472 U OPERATION VCC XOR Input Circuitry The LTC1472 ensures that the 3.3V and 5V switches are never turned on at the same time 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. This XOR function also makes it possible for the LTC1472 to work with either active-low or active-high PCMCIA VCC switch control logic (see Applications Information for further details). to ground. Both switches also have independent thermal shutdown which limits the power dissipation to safe levels. VCC Switch Truth Table VCC EN0 VCC EN1 VCC(OUT) 0 0 OFF 1 0 5V 0 1 3.3V 1 1 OFF VCC Break-Before-Make Switch Control THE VPP SWITCHING SECTION The LTC1472 has built-in delays to ensure that the 3.3V and 5V switch are non-overlapping. Further, the gate charge pumps include circuity which ramps the NMOS switches on slowly (400µs typical rise time) but turn off much more quickly (typically 10µs). The VPP switching section of the LTC1472 consists of the following functional blocks: VCC 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. An 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 1µA when both switches are turned off. VCC Gate Charge and Discharge Control Both VCC switches are designed to ramp on slowly (400µs typical rise time). Turn off time is much quicker (typically 10µs). To ensure that both VCC NMOS switch gates are fully discharged, program the switch to the high impedance mode at least 100µs before turning off the 5VIN power supply. VCC Switch Protection Two levels of protection are designed into each of the power switches in the LTC1472. Both VCC switches are protected against accidental short circuits with SafeSlot fold-back current limit circuits which limit the output current to typically 1A when the VCC(OUT) output is shorted 8 VPP Switch Input TTL-CMOS Converters The VPP inputs are designed to accommodate a wide range of 3V and 5V logic families. The input threshold voltage is 1.4V with ≈ 100mV of hysteresis. The inputs enable the bias generator, the gate charge pumps and the protection circuitry. When the inputs are turned off, the entire circuit is powered down and the VDD and VPPIN supply currents drop below 1µA. VPP Break-Before-Make Switch Control The VPP input section has built-in delays to ensure that the VPP switchs are non-overlapping. Further, the gate charge pumps include circuitry which ramps the NMOS switches on slowly but turns them off quickly. VPP Bias, Oscillator and Gate Charge Pump When either the VPPIN-VPPOUT or VCC(IN)-VPPOUT switch is enabled, a bias current generator and high frequency oscillator are turned on. An on-chip capacitive charge pump generates approximately 23V of gate drive for the internal low RDS(ON) NMOS VPPIN-VPPOUT switch from the VPPIN power supply. The gate of the VCC(IN)-VPPOUT NMOS switch is either powered by the external 12V regulator (if left on) or automatically from a built-in charge pump powered from the VDD supply when the external 12V supply drops below 10V. The VDD supply current drops below 1µA when switched to either the 0V or Hi-Z mode. LTC1472 U OPERATION VPP Gate Charge and Discharge Control The VPP switches are designed to ramp slowly (typically tens of µs) between output modes to reduce supply glitching when powering large capacitive loads. cally 100mA when protecting the 12V VPPIN supply and 60mA when protecting the VCC(IN) supply. (Higher operating currents are allowed at higher output voltages). Both switches also have thermal shutdown. VPP Switch Truth Table VPP Switch Protection VPP EN0 VPP EN1 0 0 0V 0 1 VCC(IN) 1 0 VPPIN 1 1 Hi-Z Both VPP power switches are protected against accidental short circuits with SafeSlot fold-back current limit circuits which limit the short-circuit (0V) output current to typi- VPPOUT U W U U APPLICATIONS INFORMATION The LTC1472 is a complete single slot VCC and VPP power supply switch matrix with SafeSlot current limit protection on both outputs. It is designed to interface directly with industry standard PCMCIA card controllers and to industry standard 12V regulators. 10µH COILCRAFT DO1608-103 5V 100µF 10V + 2 Interfacing to the CL-PD6710 and the LT®1301 Figure 1 shows the LTC1472 interfaced to a standard PCMCIA slot controller and an LT1301 step-up switching regulator. The LTC1472 accepts logic control directly from the CL-PD6710 and in turn, controls the LT1301 to provide clean 12V VPP programming power when required. The LT1301 is then shutdown (10µA standby current) at all other times to conserve power. The XOR VCC input function allows the LTC1472 to interface directly to the active-low VCC control outputs of the CL-PD6710 for 3.3V/5V voltage selection (see the VCC Switch Truth Table). Therefore, no “glue” logic is required to interface to this PCMCIA compatible controller. The LTC1472 provides SafeSlot current-limit protection for the LT1301 step-up regulator, the system 3.3V and 5V regulators, the socket and the card. Further, depending upon the system regulator’s own current limits, it may allow the system power supplies to continue operation during a card/slot short circuit without losing data, etc. 6 MBRS130LT3 (12V) 7 VIN SW SENSE SEL LT1301 3 ILIM SHDN PGND GND 8 1 4 + 0.1µF 5 NC 47µF 16V TANT 0.1µF 3.3V 10k 0.1µF 3VIN 5V SHDN 3VIN 0V, VCC, 12V, Hi-Z VPPIN 5VIN 0.1µF VPPOUT VCC(IN) 0.1µF VPP1 VPP2 LTC1472 CL-PD6710 PCMCIA CARD SLOT VDD VPP_PGM VPP EN0 VPP_VCC VPP EN1 VCC(OUT) VCC _3 VCC EN0 VCC(OUT) VCC _5 VCC EN1 GND OFF, 3.3V, 5V 10k GND + VCC VCC 1µF TANT LTC1472-F01 Figure 1. Direct Interface to Industry Standard PCMCIA Controller and LT1301 Step-Up Switching Regulator 9 LTC1472 U W U U APPLICATIONS INFORMATION Interfacing to “365” Type Controllers at the VDD and 5VIN supply pins for proper operation and should always be present when a card is powered (whether it is a 5V or 3.3V only card). The LTC1472 also interfaces directly with “365” type controllers as shown in Figure 2. The VCC Enable inputs are connected differently than to the CL-PD6710 controller because the “365” type controllers use active-high logic control of the VCC switches (see the VCC Switch Truth Table). No “glue logic” is required to interface to this type of PCMCIA compatible controller. If the 5V power must be turned off, for example, to enter a 3.3V only full system “sleep” mode, the 5V supply must be turned off at least 100µs after the VCC and VPP switches have been programmed to the Hi-Z or 0V states. This ensures that the gates of the NMOS switches are completely discharged. 12V Power Requirements Also, the VCC switches cannot be operated properly without 5V power. They must be programmed to the off state at least 100µs prior to turning the 5V supply off, or they may be left in an indeterminate state. Note that in Figure 2, a “local” 5V to 12V converter is not used. The LTC1472 works equally well with or without continuous 12V power. If the main power supply system has 12V continuously available, simply connect it to the VPPIN pin. Internal circuitry automatically senses its presence and uses it to switch the internal VPP switches. Supply Bypassing For best results, bypass the supply input pins with 1µF capacitors as close as possible to the LTC1472. Sometimes, much larger capacitors are already available at the outputs of the 3.3V, 5V and 12V power supply. In this case, it is still good practice to use 0.1µF capacitors as close as possible to the LTC1472, especially if the power supply output capacitors are more than 2" away on the printed circuit board. The 12V shutdown output can be used to shut down the system 12V power supply (if not required for any purpose other than VPP programming). 5V Power Requirements The LTC1472 has been designed to operate without continuous 12V power, but continuous 5V power is required 12V 12V SHUTDOWN (OPTIONAL) 10k 3.3V 0.1µF 3VIN 5V SHDN 3VIN VPPIN 5VIN 0.1µF (0V, VCC, 12V, Hi-Z) VPPOUT 0.1µF VCC(IN) LTC1472 “365”TYPE CONTROLLER VPP EN0 A_VPP_EN1 VPP EN1 A_VCC _EN0 VCC EN0 A_VCC _EN1 VCC EN1 GND VCC(OUT) (OFF, 3.3V, 5V) VCC(OUT) 10k GND VPP2 PCMCIA CARD SLOT VDD A_VPP_EN0 VPP1 + 1µF TANT VCC VCC LTC1472-F02 Figure 2. Direct Interface to Industry Standard PCMCIA Controller and LT1301 Step-Up Switching Regulator 10 LTC1472 U W U U APPLICATIONS INFORMATION Output Capacitors The VCC(OUT) pin is designed to ramp on slowly, typically 400µs rise time. Therefore, capacitors as large as 150µF can be driven without producing voltage spikes on the 5VIN or 3VIN supply pins (see graphs in Typical Performance Characteristics). The VCC(OUT) pin should have a 0.1µF to 1µF capacitor for noise reduction and smoothing. The VPPOUT pin should have a 0.01µF to 0.1µF capacitor for noise reduction. The VPPIN capacitors should be at least equal to the VPPOUT capacitors to ensure smooth transitions between output voltages without creating spikes on the system power supply lines. Supply Sequencing Because the 5V supply is the source of power for both the VCC and VPP switch control logic, it is best to sequence the power supplies such that the 5V supply is powered before or simultaneous to the application of 3.3V or 12V power. It is interesting to note however, that all of the switches in the LTC1472 are NMOS transistors which require charge pumps to generate gate voltages higher than the supply rails for full enhancement. Because the gate voltages start a 0V when the supplies are first activated, the switches always start in the off state and do not produce glitches at the output when powered. Some PCMCIA switch matrix products employ PMOS switches for 12V VPP control and great care must be taken to ensure that the 5V control logic is powered before the 12V supply is turned on. If this sequence is not followed, the PMOS VPP switch gate may start at ground potential and the VPP output may be inadvertently forced to 12V. Although, not advisable, it is possible to power the 12V VPPIN supply pin of the LTC1472 prior to application of 5V power. Only about 50µA flows to the VPPOUT pin under these conditions. If the 5V supply must be turned off, it is important to program all switches to the Hi-Z or 0V state at least 100µs before the 5V power is removed to ensure that all NMOS switch gates are fully discharged to 0V. Whenever possible however, it is best to leave the 5VIN and VDD pins continuously powered. The LTC1472 quiescent current drops to < 1µA with all the switches turned off and therefore no 5V power is consumed in the standby mode. 11 LTC1472 U TYPICAL APPLICATIONS Dual Protected PCMCIA Power Management System 33µH* COILCRAFT DO3316-333 3.3V or 5V + 100µF 10V 6 2 3 MBRS130LT3 12V 7 VIN SW SENSE SEL LT1301 ILIM SHDN PGND GND 8 1 4 + 0.1µF 5 NC 47µF 16V TANT 0.1µF 3.3V 10k 0.1µF 3VIN SHDN 3VIN VPPIN 5VIN 5V 0.1µF 0V, VCC, 12V, Hi-Z VPPOUT VCC(IN) 0.1µF VPP1 VPP2 LTC1472 PCMCIA CARD SLOT VDD A_VPP_PGM VPP EN0 A_VPP_VCC VPP EN1 VCC(OUT) A_VCC_3 VCC EN0 VCC(OUT) A_VCC_5 VCC EN1 GND OFF, 3.3V, 5V 10k + GND 3.3V 10k VCC VCC 1µF TANT 0.1µF 0.1µF CL-PD6720 3VIN SHDN 3VIN 5VIN 5V VPPIN 0.1µF 0V, VCC, 12V, Hi-Z VPPOUT VCC(IN) 0.1µF VPP1 VPP2 LTC1472 PCMCIA CARD SLOT VDD B_VPP_PGM VPP EN0 B_VPP_VCC VPP EN1 VCC(OUT) B_VCC _3 VCC EN0 VCC(OUT) B_VCC _5 VCC EN1 GND GND OFF, 3.3V, 5V 10k + *FOR 5V TO 12V CONVERSION USE 10µH, COILCRAFT DO1608-103. SEE LT1301 DATA SHEET FOR MORE DETAILED INFORMATION ON INDUCTOR AND CAPACITOR SELECTION. 12 1µF TANT VCC VCC LTC1472-TA02 LTC1472 U TYPICAL APPLICATIONS Single Protected PCMCIA Power Management System Using the LT1301 Powered from 3.3V or 5V 33µH* COILCRAFT DO3316-333 3.3V OR 5V + 100µF 10V 2 MBRS130LT3 6 7 VIN SW SEL SENSE LT1301 3 ILIM SHDN PGND GND 8 1 12V 4 + 0.1µF 5 NC 47µF 16V TANT 0.1µF 3.3V 10k 0.1µF 3VIN 5V SHDN 3VIN VPPIN 5VIN 0.1µF 0V, VCC, 12V, Hi-Z VPPOUT VCC(IN) 0.1µF LTC1472 CL-PD6710 VPP EN0 VPP_VCC VPP EN1 VCC(OUT) VCC _3 VCC EN0 VCC(OUT) VCC _5 GND OFF, 3.3V, 5V 10k VCC EN1 GND VPP2 PCMCIA CARD SLOT VDD VPP_PGM VPP1 + 1µF TANT VCC VCC LTC1472 TA03 *FOR 5V TO 12V CONVERSION USE 10µH, COILCRAFT D01608-103. SEE LT1301 DATA SHEET FOR MORE DETAILED INFORMATION ON INDUCTION AND CAPACITOR SELECTION. 13 LTC1472 U TYPICAL APPLICATIONS Single Protected PCMCIA Power Management System Using the LT1121 Powered from an Auxiliary Winding for 12V VPP Power *13V TO 20V (MAY BE FROM AUXILIARY WINDING) + 8 10µF 10V IN 5V OUT 100k 12V 1 200pF LT1121CS8 5 SHDN ADJ PGND 121k 2 GND + 1µF TANT 56.2k 3 6, 7 2N7002 3.3V 0.1µF 0.1µF 3VIN 5V SHDN 3VIN VPPIN 5VIN 0.1µF 0V, VCC, 12V, Hi-Z VPPOUT VCC(IN) 0.1µF VPP1 VPP2 LTC1472 CL-PD6710 PCMCIA CARD SLOT VDD VPP_PGM VPP EN0 VPP_VCC VPP EN1 VCC(OUT) VCC _3 VCC EN0 VCC(OUT) VCC _5 VCC EN1 GND OFF, 3.3V, 5V 10k GND + 1µF TANT VCC VCC LTC1472 TA04 *SEE THE LTC1142 DATA SHEET FOR AN EXAMPLE OF A 3.3V/5V DUAL REGULATOR WITH AUXILIARY WINDING 15V OUTPUT 14 LTC1472 U TYPICAL APPLICATIONS Dual Protected PCMCIA Power Management System Powered by System 12V Supply 12V 0.1µF 3.3V NC 0.1µF 3VIN 5V SHDN 3VIN VPPIN 5VIN 0.1µF 0V, VCC, 12V, Hi-Z VPPOUT 0.1µF VCC(IN) VPP1 VPP2 LTC1472 PCMCIA CARD SLOT VDD A_VPP_PGM VPP EN0 A_VPP_VCC VPP EN1 VCC(OUT) A_VCC _3 VCC EN0 VCC(OUT) A_VCC _5 VCC EN1 GND OFF, 3.3V, 5V 10k + GND VCC VCC 1µF TANT 12V 0.1µF CL-PD6720 3.3V NC 0.1µF 3VIN 5V SHDN 3VIN VPPIN 5VIN 0.1µF 0V, VCC, 12V, Hi-Z VPPOUT 0.1µF VCC(IN) VPP1 VPP2 LTC1472 PCMCIA CARD SLOT VDD B_VPP_PGM VPP EN0 B_VPP_VCC VPP EN1 VCC(OUT) B_VCC _3 VCC EN0 VCC(OUT) B_VCC _5 VCC EN1 GND OFF, 3.3V, 5V 10k GND + 1µF TANT 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. VCC VCC LTC1472 TA05 15 LTC1472 U PACKAGE DESCRIPTION Dimensions in inches (millimeters) unless otherwise noted. S-Package 16-lead Plastic SOIC 0.386 – 0.394* (9.804 – 10.008) 16 15 14 13 12 11 10 9 0.150 – 0.157* (3.810 – 3.988) 0.228 – 0.244 (5.791 – 6.197) 1 0.010 – 0.020 × 45° (0.254 – 0.508) 0.008 – 0.010 (0.203 – 0.254) 2 3 4 5 0.053 – 0.069 (1.346 – 1.752) 0.014 – 0.019 (0.355 – 0.483) 7 8 0.004 – 0.010 (0.101 – 0.254) 0° – 8° TYP 0.016 – 0.050 0.406 – 1.270 6 0.050 (1.270) TYP SO16 0893 *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 sheet. 16 Linear Technology Corporation LT/GP 0395 10K • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7487 (408) 432-1900 ● FAX: (408) 434-0507 ● TELEX: 499-3977 LINEAR TECHNOLOGY CORPORATION 1995