The TPS776xx devices are designed to have a fast transient response and be stable with a 10-F low ESR capacitors. This combination provides high performance at a reasonable cost. Because the PMOS device behaves as a low-value resistor, the dropout voltage is very low (typically 169 mV at an output current of 500 mA for the TPS77633) and is directly proportional to the output current. Additionally, since the PMOS pass element is a voltage-driven device, the quiescent current is very low and independent of output loading (typically 85 A over the full range of output current, 0 mA to 500 mA). These two key specifications yield a significant improvement in operating life for battery-powered systems. This LDO family also features a sleep mode; applying a TTL high signal to EN (enable) shuts down the regulator, reducing the quiescent current to 1 A at TJ = 25C. Power good (PG) of the TPS776xx is an active high output, which can be used to implement a power-on reset or a low-battery indicator. |