Diodes Incorporated AZ34063UMTR-G1

Overview

AZ34063UMTR-G1 from Diodes Incorporated is a monolithic DC-DC converter controller IC supporting step-down, step-up, and inverting topologies with 1.5A internal switch current capability, 3.0–36V input range, and adjustable output voltage via external resistor divider. It integrates a 1.25V ±2% precision reference, current-limit sensing at 300mV typical, and oscillator frequency up to 180kHz using an external timing capacitor.

For engineers reviewing the AZ34063UMTR-G1 datasheet, AZ34063UMTR-G1 pinout, AZ34063UMTR-G1 application, or AZ34063UMTR-G1 equivalent, key selection factors include peak-current-mode control architecture, Darlington vs. common-emitter switch configuration trade-offs, thermal limits in SO-8 (780 mW PD), and compatibility with standard 1N5819 diodes and 100–220 µH inductors in proven reference designs.

Technical Context

The AZ34063UMTR-G1 implements a fixed-frequency, current-mode switching controller with internal 1.25V bandgap reference, comparator-based feedback loop, and oscillator whose frequency is set by external CT capacitor (e.g., 470pF → ~100kHz). The IPK Sense pin monitors voltage across an external sense resistor to enforce 300mV current limit threshold, enabling cycle-by-cycle peak-current limiting.

Its dual-output driver stage supports both Darlington (pins 1 & 8 tied) and common-emitter (pin 8 driven externally) configurations - affecting saturation voltage (0.45V vs. 1.0V @1A) and turn-off delay - directly impacting efficiency and thermal design in high-duty-cycle applications like 5V-to-28V boost or 25V-to-5V buck converters.

Key Specifications

Pinout & Package

Available in RoHS-compliant, green SO-8 package (4.9mm × 6.0mm, 1.27mm pitch), with exposed pad not electrically connected. Thermal resistance θ_JA = 160°C/W limits continuous power dissipation to 780mW at +25°C ambient.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM2574MX-5.0/NOPB and MC34063AP1G, the AZ34063UMTR-G1 offers adjustable output, SO-8 RoHS/Green packaging, higher oscillator frequency headroom, and tighter reference tolerance - making it optimal for new designs requiring flexibility, compliance, and compactness.

Availability

AZ34063UMTR-G1 is available at Aetrix Electronics and suitable for battery chargers, ADSL modems, industrial hubs, and negative voltage power supplies requiring stable component supply, long-term lifecycle support, and RoHS/Green compliance.

Supply support for AZ34063UMTR-G1 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in power management, signal integrity, and protection solutions for industrial, computing, and communications markets.

The AZ34063U product line delivers cost-optimized, topology-flexible DC-DC controller ICs targeting applications where external component count, thermal performance, and regulatory compliance are critical design constraints.

FAQ

What is the maximum achievable output current using AZ34063UMTR-G1 in step-down configuration?

The internal switch supports 1.5A peak current, but practical continuous output depends on thermal limits and external components. In SO-8 package at +25°C ambient, 500mA is reliably achievable with proper PCB copper area and 100µF input/output capacitance, assuming 12V→5V conversion with 100kHz switching and 220µH inductor.

Can AZ34063UMTR-G1 be used in synchronous rectification designs?

No - the AZ34063UMTR-G1 lacks gate-drive outputs compatible with external MOSFETs for synchronous rectification. It is designed for use with external Schottky diodes (e.g., 1N5819) in standard buck/boost/inverting topologies. Synchronous operation would require a dedicated controller with high-side and low-side drivers.

How does the IPK Sense pin function during startup and overload conditions?

At startup, IPK Sense monitors voltage across R_SC; if it exceeds 300mV, the switch turns off immediately, limiting inrush current. During sustained overload, the device enters hiccup mode - cycling on/off - due to repeated current-limit triggering and internal thermal foldback above +150°C junction temperature.

Is there a recommended minimum timing capacitor value for stable operation?

Yes - Diodes recommends CT ≥ 220pF for reliable oscillator start-up and jitter-free operation. Values below 100pF may cause frequency instability or failure to oscillate, especially at low VCC or high temperature. Typical designs use 330pF–470pF for 80–100kHz operation with good noise immunity.