Microchip Technology TC1303B-1P0EMF

Overview

TC1303B-1P0EMF 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 on the LDO output. It delivers fixed 1.0 V on VOUT1 and fixed 3.3 V on VOUT2, operates from 2.7–5.5 V input, achieves >90% typical efficiency at heavy load, and features 65 µA total quiescent current. It is used in portable medical instruments requiring tightly regulated dual-rail supplies with processor reset signaling.

For engineers reviewing the TC1303B-1P0EMF datasheet, TC1303B-1P0EMF pinout, TC1303B-1P0EMF application, or TC1303B-1P0EMF equivalent, key selection criteria include LDO-monitored PG timing (300 ms delay), independent shutdown control per rail, 137 mV typical dropout at 200 mA for VOUT2, 2.0 MHz fixed-frequency PWM operation, and thermal/UVLO/short-circuit protection across both outputs.

Technical Context

The TC1303B-1P0EMF implements a synchronous buck topology with PFM mode transition at light loads to minimize IQ, while its LDO uses internal compensation and requires only a 1 µF ceramic output capacitor. The power-good signal is a push-pull output referenced solely to VOUT2 regulation, with 94% threshold high and 89% threshold low.

Its shutdown architecture provides independent logic-level control of each regulator: SHDN1 enables/disables the buck stage, SHDN2 controls the LDO. UVLO triggers at 2.55 V nominal with 200 mV hysteresis, and thermal shutdown activates at 165°C with 10°C hysteresis.

Key Specifications

Pinout & Package

TC1303B-1P0EMF is housed in a 10-pin 3×3 mm DFN package with exposed thermal pad (EP), rated for -40°C to +125°C junction temperature. The package supports high-power-density layouts and requires connection of EP to AGND for thermal performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TC1303B-1P0EUN, the TC1303B-1P0EMF offers identical regulation and sequencing but superior thermal performance via DFN's exposed pad; versus TPS62231DRVR, it integrates LDO and PG-reducing component count by three ICs and simplifying layout for compact portable designs.

Availability

TC1303B-1P0EMF is available at Aetrix Electronics and suitable for handheld medical instruments, USB-powered devices, and portable computers requiring stable component supply with guaranteed long-term availability and full traceability.

Supply support for TC1303B-1P0EMF 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 microcontrollers, analog components, and power management ICs, serving automotive, industrial, and consumer markets with high-reliability silicon solutions.

The TC1303 family targets space-constrained portable electronics needing dual-rail power with integrated supervision-designed specifically to replace discrete buck + LDO + reset IC combinations in battery-operated systems.

FAQ

What is the power-good (PG) behavior of TC1303B-1P0EMF?

The TC1303B-1P0EMF features a push-pull PG output that monitors only the LDO output (VOUT2). It asserts high when VOUT2 reaches 94% of its nominal value and deasserts low when VOUT2 falls below 89%, with a fixed 300 ms active timeout period. This direct-drive capability eliminates the need for an external pull-up resistor, simplifying reset circuitry in designs using TC1303B-1P0EMF.

Does TC1303B-1P0EMF support independent enable control for each output?

Yes, TC1303B-1P0EMF provides fully independent shutdown control: SHDN1 enables/disables the 1.0 V buck output (VOUT1), and SHDN2 controls the 3.3 V LDO output (VOUT2). Both inputs are active-high logic signals with thresholds defined as >45% VIN for high and <15% VIN for low, allowing precise sequencing-such as powering up VOUT2 before VOUT1 or disabling VOUT2 while keeping VOUT1 active.

What is the minimum input voltage required for TC1303B-1P0EMF to regulate both outputs?

The minimum input voltage for TC1303B-1P0EMF is determined by the higher of two conditions: 2.7 V absolute minimum, or VIN ≥ VOUTX + VDROPOUT. For VOUT1 = 1.0 V and typical buck dropout of 280 mV, minimum VIN is 1.28 V-but practical operation requires ≥2.7 V due to UVLO. For VOUT2 = 3.3 V and 137 mV LDO dropout, minimum VIN is 3.437 V. Thus, full dual-rail regulation requires VIN ≥ 3.44 V, though the device remains functional down to 2.7 V with reduced VOUT2 margin.

Can TC1303B-1P0EMF operate from a single 3.7 V Li-ion cell throughout its discharge curve?

TC1303B-1P0EMF can maintain regulation on VOUT1 (1.0 V buck) across the full 4.2 V to 2.7 V Li-ion range, but VOUT2 (3.3 V LDO) requires VIN ≥ ~3.44 V to stay in regulation. Below that, VOUT2 droops. Therefore, TC1303B-1P0EMF supports full dual-rail operation only down to ~3.44 V; for deeper discharge, consider pairing it with a buck-boost front-end or selecting a lower-VOUT2 variant like TC1303B-1P8EMF (1.8 V).

What package type and thermal characteristics does TC1303B-1P0EMF have?

TC1303B-1P0EMF uses a 10-pin 3×3 mm DFN package with exposed thermal pad (EP), achieving θJA = 41°C/W on a 4-layer board with internal ground plane and thermal vias. The EP must be soldered to AGND for effective heat dissipation. Maximum junction temperature is +125°C continuous, with thermal shutdown activating at +165°C and 10°C hysteresis-ensuring robust operation in compact, sealed enclosures where TC1303B-1P0EMF is deployed.