5

LTC1470/LTC1471

TTL-TO-CMOS

CONVERTER

OSCILLATOR

AND BIAS

GATE CHARGE

AND

DISCHARGE

CONTROL LOGIC

CHARGE

PUMP

GATE CHARGE

AND

DISCHARGE

CONTROL LOGIC

CURRENT LIMIT

AND THERMAL

SHUTDOWN

0.14

Ω

0.12

Ω

OUTPUT

BREAK-BEFORE-

MAKE SWITCH

AND CONTROL

TTL-TO-CMOS

CONVERTER

EN0

EN1

LTC1470-BD01

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.

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 con-

tinuously 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 switch-

ing between operating modes. The LTC1471 is designed

to operate

supply pins (see Applications Information section for

more detail). The enable inputs should be turned off at

least 100

that all NMOS switch gates are fully discharged and are in

the high impedance mode.

GND (Pins 5, 13): Ground Connections.

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.

(LTC1470 or 1/2 LTC1471)