TPS9125

The TPS9125 SIM supply and level shifter integrates a programmable 3-V or 5-V SIM supply, conformable to the (GSM) test specification 11.10, together with either a 3-V or 5-V level shifter, conformable to the GSM specification 11.11 and 11.12.

A charge pump of TPS9125, utilizing two external capacitors, is configured as voltage doubler to generate a 5-V supply rail from VDD. Dependent on the SIM card used, a control signal coming from the SIM card controller is applied on the MODE terminal to switch between a 3-V or 5-V supply on the SIMVCC output terminal.

A 3-V/5-V bidirectional level shifter TPS9125 translates the 3-V compatible logic signal on DATA terminal into a 5-V compatible logic signal SIMDATA terminal, and vice versa. RST and CLK are unidirectional level shifters, providing a 5-V SIMRST and SIMCLK signal from the microcontroller to the SIM card.

The SIM supply of TPS9125 is operating provided SIMPWR = 1 and VDD is sufficient (> 2.7 V). Under this condition, SIMVCC voltage is generated by the SIM supply charge pump.

A RESET terminal of TPS9125 is provided for security reasons to switch off the SIM supply and interface if the SIM card is disconnected or removed by accident.

The TPS9125 is packaged in TI's thin shrink small-outline package (PW).