Diodes Incorporated AP64500SP-EVM

Overview

AP64500SP-EVM from Diodes Incorporated is an evaluation board for the AP64500 40V, 5A synchronous buck converter IC, designed to demonstrate high-efficiency DC/DC step-down operation with programmable switching frequency (100kHz–2.2MHz), ultralow 25µA quiescent current in PFM mode, and integrated EMI-reduction features including Frequency Spread Spectrum (±6% jitter) and proprietary gate driver design. It supports 5V output at 5A with SO-8EP-packaged U1 (AP64500SP) and targets distributed power bus and consumer electronics applications.

For engineers reviewing the AP64500SP-EVM datasheet, AP64500SP-EVM pinout, AP64500SP-EVM application, or AP64500SP-EVM equivalent, this board enables rapid validation of input voltage range (3.8V–40V), output regulation accuracy (0.8V ±1% reference), thermal shutdown, OVP, cycle-by-cycle current limiting, and LDO-mode operation under light load - all critical for industrial and battery-powered system design.

Technical Context

The AP64500SP-EVM implements peak current mode control with external compensation (COMP pin), enabling stable loop response across wide VIN/VOUT combinations. Its layout integrates low-ESR ceramic capacitors (C1/C2: 10µF ×2, C5–C12: 22µF ×3), a 3.6µH shielded inductor (L1), and precision feedback resistors (R1=115kΩ, R2=22.1kΩ) to deliver 5.0V ±1% at full 5A load.

EMI mitigation is implemented via hardware-level features: FSS modulation on the RT/CLK pin, optimized PCB stack-up with dedicated ground plane (Fig. 4–5), and test-point-accessible SW node for oscilloscope probing without probe-ground-loop artifacts. The board supports synchronization to external clock (100kHz–2.2MHz) and UVLO adjustment via R6 (200kΩ).

Key Specifications

Availability

AP64500SP-EVM is available at Aetrix Electronics and suitable for distributed power bus supplies, cordless power tools, and optical networking systems requiring stable component supply, fast prototyping turnaround, and production-ready reference design validation.

Supply support for AP64500SP-EVM 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 consumer markets.

The AP64500 product line delivers high-voltage, high-current synchronous buck converters optimized for EMI-sensitive applications such as home audio, white goods, and network infrastructure where low IQ and spread-spectrum operation are mandatory.

FAQ

What input voltage range is supported on the AP64500SP-EVM?

The board supports 3.8V to 40V DC input, verified per the AP64500's absolute maximum rating (−0.3V to +42V DC). Default test setup uses 12V input, but the design accommodates 24V and 36V rails with appropriate input capacitor derating and thermal monitoring.

How do I configure the output voltage to 3.3V?

Replace R1 with 69.8kΩ (1% tolerance) and retain R2 = 22.1kΩ, per Table 1. Confirm stability by measuring output ripple (<30mVpp at 5A) and transient response (Fig. 7) using the VOUT test points and oscilloscope with short ground leads.

Does the AP64500SP-EVM support external clock synchronization?

Yes - the RT/CLK pin accepts external clock signals from 100kHz to 2.2MHz. Connect a CMOS-level clock source to JH14 (CLK_IN), disable onboard RT resistor (R7), and verify synchronization via SW node waveform on oscilloscope.

What thermal performance can be expected at 5A output?

At 12V input / 5V output / 5A load, junction temperature rise is ≤45°C above ambient (measured per Fig. 6 efficiency curve and thermal pad soldering to 2oz copper). Board operates continuously at +85°C ambient with no thermal shutdown activation.