60-nA quiescent current boost converter with supercap management

The TPS61094 is

a 60-nA IQ boost converter with supercap management. The device provides

a power supply solution for smart meter and super capacitor backup power

applications.

The TPS61094 has a wide input voltage

range and output voltage up to 5.5 V. When the TPS61094 works in buck mode and

charges the supercap, the charging current and the termination voltage are

programmable with two external resistors. When the TPS61094 works in boost mode, the

output voltage is programmable with an external resistor.

During automatic buck or boost mode

(EN = 1, MODE = 1), when the input power supply is applied, the device bypasses the

input voltage to the output while it is capable of charging a backup supercap. When

the input power supply is disconnected or lower than the output target voltage, the

TPS61094 enters boost mode and regulates output voltage from a backup supercap. The

TPS61094 consumes 60-nA quiescent current in this mode.

The TPS61094 supports true shutdown

mode (EN = 0, MODE = 1) and the forced bypass mode (EN = 0, MODE = 0). In true

shutdown mode, the TPS61094 completely disconnects the load from the input supply.

When supporting forced bypass mode, the TPS61094 connects the load to the input

voltage directly through a bypass switch and only consumes 4-nA current to achieve

long battery life.