Diodes Incorporated PAM8905PZR

Overview

PAM8905PZR from Diodes Incorporated is a 1.9W Class-D audio amplifier with integrated boost converter and battery-tracking AGC, designed for portable audio systems operating from 2.8V to 5.2V. It delivers 1.9W into 8Ω at 1% THD+N (VBAT = 3.6V), achieves 85% typical efficiency, and maintains consistent loudness across battery discharge via adaptive gain control.

For engineers reviewing the PAM8905PZR datasheet, PAM8905PZR pinout, PAM8905PZR application, or PAM8905PZR equivalent, key selection criteria include its U-WLB1520-12 package footprint, AGC inflection point configuration (VBAT/GND/float), thermal resistance (θJA = 85°C/W), and integrated short-circuit and thermal shutdown protection.

Technical Context

The PAM8905PZR integrates a 1.2MHz boost converter and a 300kHz Class-D modulator in a single die, enabling rail-boosted output voltage independent of battery sag. Its battery-tracking AGC dynamically adjusts gain based on VBAT at power-up to limit peak current draw below 2A during low-voltage operation.

DC input protection, auto-recovery short-circuit protection on both OUT+ and OUT−, and ±10mV output offset ensure robust signal integrity. The device uses dual ground domains-PGND for power switching and AGND/BGND for analog/boost reference-to minimize noise coupling between stages.

Key Specifications

Pinout & Package

Supplied in a 12-pin U-WLB1520-12 wafer-level chip-scale package (1.5mm × 2.0mm, 0.5mm pitch), optimized for ultra-thin portable designs with minimal PCB area.

Key Features

Applications

Equivalent & Alternatives

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

Compared with PAM8945PZR and MAX98357AETE+, the PAM8905PZR uniquely combines analog-differential input, battery-sensing AGC, and monolithic boost in a 1.5×2.0mm footprint-making it optimal for cost-sensitive, battery-voltage-variable analog audio systems where layout area is constrained.

Availability

PAM8905PZR is available at Aetrix Electronics and suitable for smartphones, portable Bluetooth speakers, GPS navigation devices, and wearable audio accessories requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for PAM8905PZR 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 high-efficiency power management, signal integrity, and precision analog solutions.

The PAM8905PZR belongs to Diodes' PAM audio amplifier product line, engineered specifically for space-constrained portable electronics needing high-output audio with dynamic battery compensation and minimal external components.

FAQ

What is the function of the AGC pin, and how does it affect audio output?

The AGC pin sets the battery voltage inflection point at power-up by connecting to VBAT, GND, or left floating. It configures the gain reduction threshold to limit peak battery current to ≤2A when VBAT falls below that point. This preserves loudness consistency and prevents brown-out during audio peaks, especially critical in single-cell Li-ion systems.

Can the PAM8905PZR drive a 4Ω speaker, and what is the maximum output power?

Yes, the PAM8905PZR drives 4Ω loads with up to 2.0W output at 1% THD+N (VBAT = 3.6V). Electrical characteristics confirm 0.15% THD+N at 2W/4Ω, and thermal limits remain within safe operating area due to θJA = 85°C/W and built-in thermal shutdown.

Is an external LC filter required for EMI compliance?

No external LC filter is required for basic operation-the PAM8905PZR's spread-spectrum modulation and integrated boost reduce radiated emissions. However, a 1μH/1nF RC snubber on SW and ferrite bead on PVDD are recommended for EN55032 Class B compliance in handheld enclosures.

How does the U-WLB1520-12 package impact thermal performance and PCB assembly?

The U-WLB1520-12 package uses copper pillar interconnects and exposed die attach for low thermal resistance (θJA = 85°C/W). Its 0.5mm pitch and 1.5×2.0mm footprint require stencil-controlled solder paste and 6-mil aperture for reliable reflow; IPC-7351B land pattern AP02001 is mandatory for yield.