Microchip Technology TC1303B-PF0EUN

Overview

TC1303B-PF0EUN from Microchip Technology is a dual-output power management IC integrating a 500 mA synchronous buck regulator and a 300 mA low-dropout linear regulator (LDO), with the power-good (PG) output monitoring only the LDO output (VOUT2). It delivers 1.8 V at 500 mA and 3.3 V at 300 mA, features 2.0 MHz fixed-frequency PWM operation, 65 µA typical quiescent current, and operates across –40°C to +125°C junction temperature. It targets battery-powered portable electronics requiring tightly regulated dual-rail supplies.

For engineers reviewing the TC1303B-PF0EUN datasheet, TC1303B-PF0EUN pinout, TC1303B-PF0EUN application, or TC1303B-PF0EUN equivalent, key selection criteria include LDO-monitored PG behavior, independent SHDN2 control for the LDO, 137 mV dropout at 200 mA, DFN/MSOP package compatibility, and thermal shutdown at 165°C - all critical for compact, low-power embedded designs.

Technical Context

The TC1303B-PF0EUN implements a synchronous buck stage with P- and N-channel MOSFETs (R_DS(on) = 450 mΩ each), fixed 2.0 MHz switching frequency under heavy load, and automatic transition to PFM mode at light loads to maintain ultra-low IQ. Its LDO stage uses internal compensation and achieves ±0.3% output voltage tolerance with 25 ppm/°C temperature coefficient.

Power-good logic is configured exclusively for VOUT2 regulation (94% threshold, 300 ms delay), and PG is implemented as a push-pull output - distinguishing it from TC1303A/C and TC1304 variants. Shutdown is independently controlled via SHDN1 (buck) and SHDN2 (LDO), enabling flexible power sequencing in multi-rail systems.

Key Specifications

Pinout & Package

TC1303B-PF0EUN is housed in a 10-pin 3×3 mm DFN package with exposed thermal pad (EP), pin-compatible with the MSOP variant. The EP must be connected to AGND for thermal performance and noise immunity.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-output PMIC applications.

Compared with TC1303C-PF0EUN and TPS65023RGZR, TC1303B-PF0EUN provides the most direct solution for cost-sensitive, space-constrained applications requiring LDO-only PG monitoring and minimal external components - with no compromise on thermal robustness or load transient response.

Availability

TC1303B-PF0EUN is available at Aetrix Electronics and suitable for wearable health monitors, USB-C powered IoT hubs, and industrial handheld scanners requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for TC1303B-PF0EUN includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Microchip Technology is a U.S.-based semiconductor company specializing in microcontrollers, analog devices, and power management ICs, with vertical integration from design to wafer fabrication and test.

The TC1303 family was designed specifically for portable and battery-operated applications demanding high efficiency, ultra-low quiescent current, and dual-rail flexibility in minimal PCB area - targeting medical, consumer, and industrial edge devices.

FAQ

What output voltages does the TC1303B-PF0EUN provide?

The TC1303B-PF0EUN provides fixed 1.8 V from its buck regulator (VOUT1) and fixed 3.3 V from its LDO (VOUT2), as indicated by the "PF0EUN" suffix per Microchip's part numbering scheme. Both outputs are internally set and require no external resistive dividers. The 1.8 V rail supports low-voltage digital cores, while the 3.3 V rail powers analog circuitry, interfaces, and peripherals - making TC1303B-PF0EUN ideal for mixed-signal portable systems.

How does the power-good (PG) function operate in the TC1303B-PF0EUN?

In the TC1303B-PF0EUN, the PG output is a push-pull signal that asserts high only when the LDO output (VOUT2) reaches and maintains ≥94% of its nominal 3.3 V value, with a built-in 300 ms delay to prevent false resets during startup. This differs from TC1303A (PG monitors buck only) and TC1303C (PG monitors both rails). The PG pin directly drives processor RESET lines without external pull-ups, simplifying system-level reset architecture for TC1303B-PF0EUN designs.

What package options are available for the TC1303B-PF0EUN?

The TC1303B-PF0EUN is offered in a 10-pin 3×3 mm DFN package with exposed thermal pad (EP), designated by the "EUN" suffix. It is pin-compatible with the 10-lead MSOP variant, allowing layout reuse across form factors. The DFN package provides superior thermal performance (θ_JA = 41°C/W on 4-layer board) versus MSOP (113°C/W), making it preferred for thermally constrained applications - and the EP must be soldered to AGND for optimal junction temperature control in TC1303B-PF0EUN deployments.

Does the TC1303B-PF0EUN support independent enable control for each regulator?

Yes, the TC1303B-PF0EUN provides fully independent shutdown control: SHDN1 enables/disables the buck regulator (VOUT1), and SHDN2 enables/disables the LDO (VOUT2). Both inputs are active-high logic-level signals (VIH > 45% VIN, VIL < 15% VIN) with ±0.01 µA leakage. This allows precise power sequencing - for example, enabling the LDO first to power bias circuitry before enabling the buck for digital core - a capability confirmed in the functional block diagram and electrical characteristics table of the TC1303B-PF0EUN datasheet.

What protection features are integrated into the TC1303B-PF0EUN?

The TC1303B-PF0EUN integrates undervoltage lockout (UVLO) triggering at 2.55 V (with 200 mV hysteresis), overtemperature shutdown at 165°C (with 10°C hysteresis), and output short-circuit protection limiting average LDO fault current to 240 mA. The buck stage includes cycle-by-cycle current limiting, and both regulators feature internal soft-start. These protections are active across the full –40°C to +125°C operating range and require no external components - ensuring robust field operation of TC1303B-PF0EUN in unattended or harsh-environment applications.