Microchip Technology TC1303B-ZI0EMF

Overview

TC1303B-ZI0EMF 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 specifically tied to the LDO output. It delivers fixed 2.5 V on VOUT1 and 3.3 V on VOUT2, operates from 2.7–5.5 V input, features 65 µA typical quiescent current, and supports -40°C to +125°C junction temperature - used in portable medical instruments for stable dual-rail biasing.

For engineers reviewing the TC1303B-ZI0EMF datasheet, TC1303B-ZI0EMF pinout, TC1303B-ZI0EMF application, or TC1303B-ZI0EMF equivalent, key selection considerations include LDO-monitored PG behavior, independent shutdown control per rail, 2.0 MHz fixed-frequency PWM operation with automatic PFM transition, 137 mV typical dropout at 200 mA, and DFN/MSOP package compatibility with minimal external components.

Technical Context

The TC1303B-ZI0EMF implements a synchronous buck stage with integrated P-channel and N-channel MOSFETs (R_DS(on) = 450 mΩ each), operating at 2.0 MHz nominal switching frequency under heavy load and transitioning automatically to PFM mode at light loads to maintain ultra-low IQ. Its LDO stage uses internal compensation and achieves 137 mV dropout at 200 mA with ±0.3% output voltage tolerance.

Power-good logic monitors only the LDO output (VOUT2) with 94% threshold high, 89% threshold low, 2% hysteresis, and a 300 ms active delay - configured as a push-pull output (unlike open-drain variants). UVLO triggers at 2.55 V (typ) with 200 mV hysteresis, and thermal shutdown activates at 165°C with 10°C hysteresis.

Key Specifications

Pinout & Package

TC1303B-ZI0EMF is packaged in a 10-lead 3×3 mm DFN with exposed thermal pad (EP), pin-compatible with MSOP-10. The exposed pad must be soldered to AGND for thermal and electrical performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TC1303C-ZI0EMF and TPS65023RGZR, TC1303B-ZI0EMF provides the most direct LDO-only power-good signaling and lowest quiescent current for cost-sensitive, space-constrained medical and USB applications - without requiring layout changes or additional support components.

Availability

TC1303B-ZI0EMF is available at Aetrix Electronics and suitable for handheld medical instruments, USB-powered devices, and cellular phones requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for TC1303B-ZI0EMF 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 manufacturer specializing in microcontrollers, analog devices, and power management ICs for industrial, automotive, and consumer markets.

The TC1303 family was designed to deliver highly integrated, low-quiescent-current dual-rail power solutions for battery-operated portable electronics - emphasizing minimal external components, robust protection, and precise output regulation.

FAQ

What output voltages does the TC1303B-ZI0EMF provide?

The TC1303B-ZI0EMF provides fixed 2.5 V on its buck output (VOUT1) and fixed 3.3 V on its LDO output (VOUT2). These values are factory-trimmed and require no external feedback resistors. The device does not support adjustable output configurations - unlike TC1303A/B/C variants with VFB pins, the ZI0EMF suffix denotes this specific fixed-voltage combination.

How does the power-good (PG) function operate in TC1303B-ZI0EMF?

In TC1303B-ZI0EMF, the PG pin is a push-pull output that monitors only the LDO output (VOUT2). It asserts high when VOUT2 reaches ≥94% of its nominal value and deasserts when VOUT2 falls ≤89%. A built-in 300 ms delay ensures clean processor reset timing. This differs from TC1303A (open-drain, monitors buck) and TC1303C (monitors both rails).

Can TC1303B-ZI0EMF operate from a single-cell Li-ion battery?

Yes - TC1303B-ZI0EMF supports input voltages from 2.7 V to 5.5 V, covering the full discharge curve of a single-cell Li-ion (2.7–4.2 V). Its 137 mV LDO dropout at 200 mA ensures the 3.3 V output remains regulated down to 3.43 V input, maximizing usable battery capacity before brownout.

What package type is used for TC1303B-ZI0EMF?

TC1303B-ZI0EMF is supplied in a 10-lead 3×3 mm DFN package with an exposed thermal pad (EP). The part number suffix "ZI0EMF" explicitly denotes this DFN variant. It is pin-compatible with the 10-lead MSOP package but offers superior thermal performance (θ_JA = 41°C/W vs. 113°C/W) due to the EP connection to AGND.

Does TC1303B-ZI0EMF support independent enable control for each output?

Yes - TC1303B-ZI0EMF provides two independent shutdown inputs: SHDN1 controls the buck regulator only, and SHDN2 controls the LDO only. Both are active-high logic inputs requiring >45% of VIN to enable. This allows flexible power sequencing - for example, enabling the LDO first to power real-time clocks before bringing up the processor rail.