Microchip Technology TC1303A-UA0EMF

Overview

TC1303A-UA0EMF 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 power-good monitoring focused exclusively on the buck output (VOUT1). It delivers 90% typical efficiency at 2.0 MHz switching frequency, features 65 µA total quiescent current, and supports adjustable (0.8–4.5 V) or fixed-output voltages. It is designed for space-constrained portable electronics requiring tightly regulated core and I/O rails.

For engineers reviewing the TC1303A-UA0EMF datasheet, TC1303A-UA0EMF pinout, TC1303A-UA0EMF application, or TC1303A-UA0EMF equivalent, key selection criteria include its buck-only power-good function, independent shutdown control for each regulator, internal compensation, 137 mV LDO dropout at 200 mA, and operation across –40°C to +125°C junction temperature.

Technical Context

The TC1303A-UA0EMF implements a fixed-frequency PWM buck stage operating at 2.0 MHz under heavy load, automatically transitioning to PFM mode at light loads to maintain ultra-low quiescent current. Its LDO stage uses a single 1 µF ceramic output capacitor and exhibits ±0.3% output voltage tolerance over temperature and line/load variations.

Power-good logic monitors only the buck output (VOUT1), asserting an open-drain PG signal after a 300 ms delay when VOUT1 reaches ≥94% of regulation. Undervoltage lockout (2.55 V nominal) and thermal shutdown (165°C) provide system-level protection without external components.

Key Specifications

Pinout & Package

The TC1303A-UA0EMF is housed in a 10-pin 3×3 mm DFN package with exposed thermal pad (EP), optimized for high thermal performance on compact PCBs. Pin 11 (EP) must be soldered to AGND for proper thermal dissipation and noise immunity.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP16311-H/MS and TPS65023RSBR, the TC1303A-UA0EMF uniquely balances dual-rail integration, ultra-low IQ, and minimal 3×3 mm DFN footprint - making it optimal for size- and battery-life-constrained portable designs where exactly two regulated outputs are needed.

Availability

TC1303A-UA0EMF is available at Aetrix Electronics and suitable for cellular phones, USB-powered devices, and handheld medical instruments requiring stable component supply with guaranteed long-term availability and full traceability.

Supply support for TC1303A-UA0EMF 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 leading provider of microcontroller, mixed-signal, analog, and Flash-IP solutions, serving automotive, industrial, consumer, and communications markets with high-reliability silicon and development tools.

The TC1303 family is part of Microchip's Power Management portfolio, engineered specifically for portable and battery-operated systems needing high-efficiency, low-quiescent-current dual-rail regulation in minimal footprint packages.

FAQ

What is the power-good (PG) behavior of the TC1303A-UA0EMF?

The TC1303A-UA0EMF features an open-drain PG output that monitors only the buck regulator output (VOUT1). It asserts low after a fixed 300 ms delay once VOUT1 reaches ≥94% of its nominal value. The PG signal remains active until VOUT1 drops below 92% of regulation, providing reliable reset timing for processors and FPGAs. This behavior is fixed per the TC1303A variant designation and cannot be reconfigured.

Can the TC1303A-UA0EMF generate adjustable output voltages?

Yes, the TC1303A-UA0EMF supports adjustable buck output (VOUT1) from 0.8 V to 4.5 V using an external resistor divider connected to the VFB1/VOUT1 pin. The LDO output (VOUT2) is factory-fixed - for TC1303A-UA0EMF, VOUT2 is 2.5 V. The device's internal 0.8 V reference and ±0.3% tolerance ensure precise regulation across temperature and load conditions.

What are the thermal limitations of the TC1303A-UA0EMF in its DFN package?

The TC1303A-UA0EMF in the 10-pin 3×3 mm DFN package has a typical θJA of 41°C/W on a 4-layer board with internal ground plane and thermal vias under the exposed pad (EP). Maximum junction temperature is +150°C transient and +125°C continuous. To stay within safe operating limits at full 500 mA buck + 300 mA LDO load, ambient temperature must remain ≤85°C with adequate copper pour and ≥4 thermal vias connecting EP to AGND.

How does the TC1303A-UA0EMF manage efficiency across load ranges?

The TC1303A-UA0EMF uses automatic PWM-to-PFM mode transition: at heavy loads (>100 mA), it operates in fixed 2.0 MHz PWM mode for high efficiency (>90% at 500 mA); at light loads (<10 mA), it shifts to PFM to reduce switching losses and maintain 65 µA total IQ. This preserves efficiency across four decades of load current without requiring external mode-control signals or configuration registers.

Is the TC1303A-UA0EMF pin-compatible with other TC1303 variants?

No - the TC1303A-UA0EMF is not pin-compatible with TC1303B, TC1303C, or TC1304 variants. While all share the same 10-pin DFN/MSOP footprint and basic pinout, the TC1303A uses separate SHDN1/SHDN2 inputs and open-drain PG, whereas TC1303B uses push-pull PG and shares a single SHDN, and TC1304 adds sequencing logic. Substituting variants requires PCB layout changes and firmware updates to match control signal behavior.