Diodes Incorporated AZ494AMTR-E1

Overview

AZ494AMTR-E1 from BCD Semiconductor Manufacturing Limited is a voltage-mode PWM controller IC designed for switching power supply regulation, featuring a 4.95V ±1% trimmed reference, dual error amplifiers, on-chip oscillator (1–200 kHz), dead-time control, and selectable single-ended or push-pull output operation in SOIC-16 package. It enables precise output voltage regulation in step-down converters and backlight inverters.

For engineers reviewing the AZ494AMTR-E1 datasheet, AZ494AMTR-E1 pinout, AZ494AMTR-E1 application, or AZ494AMTR-E1 equivalent, key selection criteria include reference accuracy (±1%), oscillator frequency range (1–200 kHz), dual-error-amplifier architecture, dead-time control comparator, and 200 mA sink/source TR output capability.

Technical Context

The AZ494AMTR-E1 implements voltage-mode PWM control with two independent error amplifiers supporting feedback from primary and secondary sides, enabling flexible regulation topologies. Its internal oscillator supports master/slave operation via RT/CT pins, and its DTC comparator enforces minimum off-time to prevent shoot-through in push-pull configurations.

Output control logic selects between single-ended (CTRL = GND) and push-pull (CTRL = VREF) modes, while the pulse-steering flip-flop ensures non-overlapping drive signals. The precision 4.95V reference is trimmed at wafer level, delivering ±1% accuracy over –40°C to +85°C without external calibration.

Key Specifications

Pinout & Package

Package: SOIC-16 (3.9 mm × 9.9 mm, 1.27 mm pitch), RoHS-compliant lead-free (E1 suffix), thermal resistance R_θJA = 73°C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PWM controller applications.

Compared with UC3844B and TL494, the AZ494AMTR-E1 delivers integrated dead-time control and guaranteed 4.95 V ±1% reference in a compact SOIC-16 package-reducing external component count and improving reliability in dual-loop SMPS and inverter applications.

Availability

AZ494AMTR-E1 is available at Aetrix Electronics and suitable for SMPS design, CCFL backlight inverters, lithium-ion battery chargers, and industrial DC-DC isolated supplies requiring stable component supply and RoHS-compliant packaging.

Supply support for AZ494AMTR-E1 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

BCD Semiconductor Manufacturing Limited is a Shanghai-based analog and power IC designer specializing in high-reliability, cost-optimized controllers and drivers for power conversion.

The AZ494A/C series targets mid-power switching regulators where precision reference, dual-loop flexibility, and integrated dead-time control reduce system complexity-especially in industrial, consumer, and display power applications.

FAQ

What is the maximum allowable timing capacitor value for stable oscillator operation?

The datasheet specifies CT ≤ 10 µF for reliable oscillator function. At CT = 10 µF with RT = 500 kΩ, f_OSC drops to ~1 kHz-still within specification-but larger values increase start-up delay and reduce frequency stability over temperature. For designs above 100 kHz, CT should be ≤ 0.01 µF per Figure 8.

Can AZ494AMTR-E1 drive MOSFETs directly without external gate drivers?

Yes-the TR output delivers 200 mA sink/source current and supports emitter-follower or common-emitter configurations. It can directly drive logic-level MOSFETs with Q_g < 20 nC at ≤ 200 kHz. For high-side N-channel or high-frequency (>300 kHz) operation, an external driver is recommended due to limited slew rate and lack of bootstrap support.

How does the dead-time control (DTC) pin affect push-pull operation?

The DTC pin sets a voltage threshold (typically 3.3 V) that forces minimum off-time between complementary outputs. When DTC voltage falls below threshold, the controller inserts blanking time to prevent both transistors from conducting simultaneously-critical for avoiding shoot-through in half-bridge or full-bridge topologies with inductive loads.

Is the 4.95 V reference usable as a precision voltage source for external circuitry?

Yes-the reference is trimmed to ±1% over –40°C to +85°C and rated for 10 mA output current. Load regulation is 15 mV max from 1 mA to 10 mA, making it suitable for biasing op-amps, ADC references, or sensor excitation-provided total load current stays within spec and PCB layout minimizes noise coupling to REF pin.