LDO Integrates Switch With Dual Current Limiting

Billed as the industry's first family of ICs combining a low-dropout (LDO) regulator and a single switch with a dual current limit for power management in USB applications, the TPS2140/41/50/51 are compliant with both the USB 1.0 and 2.0 specifications. The integrated MOSFET switch features two current limits. At power-up, output current is limited to 100 mA, allowing peripherals to employ high-value capacitance to stabilize the voltage from the bus. Once the output voltage is established, the current limit increases to 800 mA minimum, providing short circuit protection. The integrated, 250-mA LDO with enable and current limit functions regulates a 2.7V to 5.5V input down to an adjustable 0.9V to 3.3V output. Both the switch and the LDO power supplies feature undervoltage lockout and power-good functions. The devices typically draw 85 µA of supply current. Available in a 14-pin HTSSOPs with 3.3V or 5V switches and active high or low states, the TPS2140, TPS2141, TPS2150 and TPS2151 are priced at $1.05 each/1,000. TEXAS INSTRUMENTS INC., Santa Clarita, CA. (800) 477-8924, ext. 4500.