Overview of Texas Instruments TPS70102PWP

The TPS70102PWP is a dual-output low-dropout (LDO) voltage regulator with integrated supervisory and power-on-reset (POR) functions, designed by Texas Instruments. It is intended for high-performance applications that require tight regulation, sequencing capabilities, and system monitoring in a compact form. With both fixed and adjustable output rails, this device is especially suitable for powering DSPs, microcontrollers, FPGAs, and mixed-voltage digital/analog systems.

Core Functionality

The TPS70102PWP integrates two LDO regulators—one with a fixed output and one adjustable—alongside supervisory circuitry, watchdog timers, and enable pins for power sequencing. It allows for independent or synchronized power-up/down control of dual voltage rails, making it ideal for complex multi-rail systems.

* LDO1: Adjustable output voltage regulator
* LDO2: Fixed output voltage regulator (set to 1.2 V in the TPS70102 variant)
* Supervisory Function: Built-in Power-On Reset (POR) and watchdog timer for system reliability
* Sequencing: Start-up sequencing and output voltage monitoring

Electrical Characteristics

* Input Voltage Range: 2.7 V to 6.5 V
* Output Voltage 1 (Adjustable): 1.5 V to 5.5 V via external resistor divider
* Output Voltage 2 (Fixed): 1.2 V nominal (TPS70102 version)
* Maximum Output Current:

* LDO1: Up to 500 mA
* LDO2: Up to 250 mA
* Dropout Voltage: Typically 200 mV at 250 mA, ensuring good regulation close to V\_IN
* Accuracy:

* ±2% over line, load, and temperature for both outputs
* Quiescent Current: Typically 170 µA per regulator when enabled
* Shutdown Current: Less than 1 µA when both regulators are disabled

Supervisory and Watchdog Features

* Power-On Reset (POR): Monitors LDO output voltages and asserts RESET when they fall below threshold
* Reset Delay Time: Programmable using an external capacitor (typically in the range of tens to hundreds of milliseconds)
* Watchdog Timer: Monitors system activity and triggers a reset if software fails to respond within a preset time window
* Manual Reset Input (MR): Provides user-initiated reset functionality
* Logic-compatible Enable Pins: Allow individual control over each LDO regulator

Thermal and Packaging

* Thermal Shutdown: Protects the device from overheating by disabling the regulators
* Current Limit Protection: Built-in protection to guard against short circuits or overloads
* Package Type: HTSSOP-20 (PWP)
* Thermal Performance: Exposed pad for efficient heat dissipation
* Operating Temperature Range: –40°C to +125°C (automotive and industrial grade)

Pin Configuration and Functionality

The TPS70102PWP is packaged in a 20-pin HTSSOP layout, with the following key functions assigned to pins:

* VIN (supply input), VOUT1 (adjustable), VOUT2 (fixed 1.2V)
* EN1, EN2: Enable pins for regulators
* RESET, MR: Reset output and manual reset input
* WDI: Watchdog input
* GND, PGND: Ground and power ground
* VBIAS: Separate bias voltage input for low quiescent operation
* Capacitor pins for soft-start and delay timing (CT, Cdly)

Applications

The TPS70102PWP is ideally suited for systems requiring both power regulation and supervisory control, such as:

* DSPs and FPGAs requiring dual-voltage power rails
* Embedded controllers and processors in industrial and automotive environments
* Telecom equipment, baseband processors, and memory power supplies
* Portable and battery-powered devices needing reliable start-up and reset logic

Summary of Key Specifications

| Feature | Specification |
| ------------------------------ | ------------------------------------ |
| Input Voltage Range | 2.7 V – 6.5 V |
| Output Voltage 1 (Adjustable) | 1.5 V – 5.5 V |
| Output Voltage 2 (Fixed) | 1.2 V (TPS70102 version) |
| Max Output Current (LDO1/LDO2) | 500 mA / 250 mA |
| Dropout Voltage @250mA | ~200 mV (typical) |
| Output Accuracy | ±2% |
| Quiescent Current (Active) | 170 µA per LDO |
| Shutdown Current | < 1 µA |
| POR Threshold Accuracy | ±2% |
| Reset Delay | Programmable via external capacitor |
| Watchdog Timeout | Programmable |
| Package | 20-pin HTSSOP (PWP) with exposed pad |
| Temperature Range | –40°C to +125°C |

Conclusion

The TPS70102PWP from Texas Instruments is a highly integrated dual LDO regulator designed to simplify power sequencing and system supervision in modern embedded designs. With its flexible power architecture, watchdog and reset functions, and precise voltage regulation, it meets the needs of high-reliability systems where power integrity and fault tolerance are critical. Its compact package with good thermal properties makes it ideal for space-constrained and thermally demanding environments.