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MAX3243E: "Ioff" support for RS232 transceivers

Part Number: MAX3243E

For a new development I require a single-supply (3V3) RS232 transceiver (3x Drivers, 5x Receivers e.g. typical PC). Previous designs have used the MAX3243E device.

For this new design it is possible for the RS232 transceiver to be completely powered off (i.e. Vcc = 0V), but for its logic inputs (i.e. DIN1, DIN2, DIN3 in the case of the MAX3243E) to still be driven (i.e. 3V3).

In this situation I am concerned with device latch-up, and back-driving through DIN1..3 inputs to the transceiver's supply pin.

The MAX3243E's datasheet specifies pin states and leakage currents whilst in a 'power-down' state (i.e. /FORCEOFF = 0V), but this is specified for normal Vcc operating voltages. It makes no mention of leakage currents whilst Vcc=0V.

For TI devices, I would normally be looking for an 'Ioff' specification in the datasheet.

Is the MAX3243E suitable for this scenario? If not can anybody recommend an RS232 transceiver with Ioff protection? Or, do I need to add an isolating buffer (with Ioff specified) in between the RS232 transceiver and my 3V3 logic drivers?