Diodes Incorporated PAM8320RDR

Overview

PAM8320RDR from Diodes Incorporated is a 20W mono Class-D audio power amplifier in SO-16EP package, designed for bridge-tied-load (BTL) operation into 4Ω speakers at 12V supply. It delivers 95% peak efficiency, integrates internal oscillator and thermal/short-circuit protection with auto-recovery, and eliminates external heat sinks in typical audio playback conditions.

For engineers reviewing the PAM8320RDR datasheet, PAM8320RDR pinout, PAM8320RDR application, or PAM8320RDR equivalent, key selection criteria include BTL output capability, 4.5–15V operating range, mute/shutdown logic interface, and SO-16EP thermal pad layout compatibility with PCB copper plane design.

Technical Context

The PAM8320RDR implements a fully integrated Class-D BTL architecture with dual NMOS half-bridge outputs driven by internal bootstrap circuitry (BSP/BSN pins), requiring external 220nF ceramic capacitors per channel. Its internal bias generator (VCM) sets analog reference level, and VCLAMP regulates gate voltage to prevent NMOS overvoltage.

It features independent power domains: PVCCP/PVCCN for positive/negative H-bridge supplies, AVCC for analog core, and separate AGND/PGNDP/PGNDN ground paths to minimize noise coupling. Protection functions-thermal shutdown (160°C trip, 40°C hysteresis), short-circuit detection, OVP (18V), and UVLO (4.4V)-are all non-latching and self-recovering.

Key Specifications

Pinout & Package

Package: SO-16EP (10.3mm × 7.5mm × 1.75mm), thermally enhanced with exposed thermal pad soldered to PCB copper plane.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar mono Class-D audio amplifier applications.

Compared with TPA3110D2PWPR and MAX9718ETA+, the PAM8320RDR offers superior integration (internal oscillator, VCLAMP, single-ended input), higher efficiency (95% vs. ≤85%), and simpler BOM-making it optimal for cost-sensitive mono audio systems needing 20W output in SO-16EP.

Availability

PAM8320RDR is available at Aetrix Electronics and suitable for PC speaker modules, Bluetooth audio systems, and docking station designs requiring stable component supply, consistent SO-16EP thermal performance, and long-term production continuity.

Supply support for PAM8320RDR 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 semiconductor company specializing in discrete, analog, and mixed-signal ICs, with emphasis on power management, signal integrity, and audio solutions for consumer and industrial markets.

The PAM8320 belongs to Diodes' Class-D audio amplifier product line, engineered for high-efficiency, low-EMI mono amplification in space- and thermal-constrained consumer audio applications.

FAQ

What is the minimum recommended VCM capacitor value and why?

A minimum 0.47μF capacitor is required on the VCM pin to ensure stable internal bias generation during startup and recovery from shutdown. This value controls the ramp rate of the internal reference voltage, preventing audible pop noise. The capacitor must be low-ESR ceramic or tantalum and placed within 5mm of the VCM pin to maintain noise immunity.

How does the PAM8320RDR achieve pop-free startup without external sequencing?

The PAM8320RDR integrates an internal current source that ramps VCM to ½VCC before enabling outputs, combined with automatic muting until reference stabilization. This eliminates turn-on transients without requiring external microcontroller coordination or complex power sequencing-critical for plug-and-play audio systems.

Can the PAM8320RDR drive 8Ω loads, and what is the expected output power?

Yes-the PAM8320RDR drives 8Ω BTL loads with up to 15W output at 1% THD+N and 12V supply. Efficiency remains above 90%, but maximum power drops versus 4Ω due to current limit and thermal constraints. For 8Ω applications, PCB copper area should still meet SO-16EP thermal guidelines to sustain continuous output.

What are the critical PCB layout requirements for thermal performance?

The SO-16EP thermal pad must be soldered to ≥35μm thick copper on both PCB sides, with 9–16 plated-through vias (0.3mm diameter minimum) connecting to inner/outer ground planes. No solder mask over thermal vias or adjacent copper areas is permitted. Decoupling capacitors (0.1μF ceramic + 470μF bulk) must be placed within 3mm of respective PVCC pins.