The TPS3513 is designed to optimize PC switching power supply system with minimum external components. It provides undervoltage lockout (UVLO), protection circuits, power good indicator, and on/off control.

UVLO thresholds are 4.45 V (on) and 3.65 V (off). Overcurrent protection (OCP) and overvoltage protection (OVP) monitor 3.3 V, 5 V, and 12 V. When an OC or OV condition is detected, the power-good output (PGO) is asserted low and the fault protection output (FPO) is latched high. PSON from low-to-high resets the latch. The OCP function will be enabled 75 ms after PSON goes low, and a debounce of typically 38 ms. A built-in 2.3-ms delay with 38-ms debounce from PSON to FPO output is enabled at turnoff.

An external resistor is connected between the RI pin and the GND pin. This will introduce an accurate I(ref) for OCP function. The I(ref) range is from 12.5 µA to 62.5 µA. The formula for choosing RI resistor is V(RI)/I(ref). Three OCP comparators and the I(ref) section are supplied by VS12. The current draw from the VS12 pin is less than 1 mA.

The power good feature monitors PGI, 3.3 V and 5 V, and issues a power good signal when the output is ready.

The TPS3513 is characterized for operation from –40°C to 85°C.

• Overvoltage Protection and Lockout for 12 V, 5 V, and 3.3 V
• Overcurrent Protection and Lockout for 12 V, 5 V, and 3.3 V
• Undervoltage Protection and Lockout for 12 V, and Undervoltage Detect for 5 V and 3.3 V
• Fault-Protection Output With Open Drain Output Stage
• Open-Drain, Power Good Output Signal for Power-Good Input, 3.3 V and 5 V
• 300-ms Power-Good Delay
• 75-ms Delay for 5-V and 3.3-V Power Supply Short-Circuit Turnon Protection
• 2.3 ms PSON Control to FPO Turnoff Delay
• 38 ms PSON Control Debounce
• Wide Supply Voltage Range From 4.5 V to 15 V