The TPS789xx family of low-dropout (LDO) voltage regulators offers the benefits of low-dropout voltage, ultralow-power operation,
low-output noise, and miniaturized packaging. These regulators feature low-dropout voltages and ultralow quiescent current compared to
conventional LDO regulators. An internal resistor, in conjunction with an external bypass capacitor, creates a low-pass filter to reduce the noise. The
TPS78930 exhibits only 56 uVRMS of output voltage noise using 0.01 uF bypass and 10 uF output capacitors. Offered in a 5-terminal small
outline integrated-circuit SOT-23 package, the TPS789xx series devices are ideal for micropower operations, low output noise, and
where board space is limited.
The usual PNP pass transistor has been replaced by a PMOS pass element. Because the PMOS pass element behaves as a low-value resistor, the
dropout voltage is very low, typically 115 mV at 100 mA of load current (TPS78930), and is directly proportional to the load current. The
quiescent current is ultralow (17 uA typically) and is stable over the entire range of output load current (0 mA to 100 mA). Intended for use in
portable systems such as laptops and cellular phones, the ultralow-dropout voltage feature and ultralow-power operation result in a significant
increase in system battery operating life.
The TPS789xx also features a logic-enabled sleep mode to shut down the regulator, reducing quiescent current
to 1 uA typical at TJ = 25°C. The TPS789xx is offered in 1.5 V, 1.8 V, 2.5 V, 2.8 V, and 3.0 V.