STMicroelectronics DEMOTS488S

Overview

DEMOTS488S from STMicroelectronics is a dual-channel, pop-and-click-noise-suppressed stereo headphone amplifier IC designed for low-voltage portable audio systems. It delivers up to 120 mW per channel into 16 Ω at 5 V (0.1% THD+N), operates from 2.2 V to 5.5 V, features active-low standby mode with 10 nA typical current, and uses external gain-setting resistors for unity-gain stability. It targets space-constrained mobile and embedded audio interfaces requiring high SNR and crosstalk immunity.

For engineers reviewing the DEMOTS488S datasheet, DEMOTS488S pinout, DEMOTS488S application, or DEMOTS488S equivalent, this page provides verified functional identity, DFN8 package mapping, confirmed electrical specs (including PSRR = 70 dB @ 1 kHz, SNR = 105 dB A-weighted, crosstalk = –102 dB), thermal derating curves, and real-world design context for headset driver implementation.

Technical Context

The TS488 is a dual, single-ended output Class-AB audio power amplifier with rail-to-rail output swing, internally compensated for unity-gain stability, and configured via external feedback and inverting input resistors (AV = –R_feed/R_in). Its pop/click suppression circuitry eliminates turn-on/turn-off transients without requiring external mute sequencing.

It integrates short-circuit protection and thermal shutdown, supports load impedances ≥16 Ω, and achieves ultra-low standby current (10 nA typ.) via an active-low STDBY pin that disables bias current paths while preserving internal node states. PSRR of 70 dB (1 kHz) and 62–68 dB (217 kHz) enables robust operation in noisy DC-DC supply environments.

Key Specifications

Pinout & Package

DEMOTS488S is housed in a thermally enhanced DFN8 (2 mm × 2 mm, 0.5 mm pitch) package with exposed thermal pad (EP) on underside for PCB heat dissipation. Pin 1 is marked by laser etch or dot; orientation follows JEDEC MO-229 standard.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-channel headphone amplifier applications.

Compared with DEMOTS488S, MAX98304 offers superior power efficiency but adds EMI-sensitive filtering complexity, while TAS5707 shifts system architecture toward digital domain integration-neither replicates the TS488's analog simplicity, ultra-low standby current, or seamless pop-free analog interface.

Availability

DEMOTS488S is available at Aetrix Electronics and suitable for mobile phone audio subsystems, portable media player designs, and computer motherboard headphone jacks requiring stable component supply, long-lifecycle support, and guaranteed traceable sourcing.

Supply support for DEMOTS488S 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, specializing in analog, power, microcontrollers, and sensors for automotive, industrial, and consumer markets.

The TS488 belongs to ST's low-power audio amplifier product line, engineered specifically for portable and battery-operated devices demanding high audio fidelity, minimal power consumption, and robust transient immunity in compact form factors.

FAQ

What is the minimum recommended supply voltage for reliable operation?

The DEMOTS488S is fully specified down to 2.2 V, with guaranteed performance including 31 mW/channel into 16 Ω at 2.5 V (0.1% THD+N). Operation below 2.2 V risks degraded PSRR, increased THD+N, and potential instability due to insufficient headroom for internal biasing-ST does not characterize or guarantee functionality below this limit.

How is pop-and-click suppression implemented without external components?

The TS488 integrates internal soft-start circuitry that sequences bias current activation and output stage ramp-up/down during STDBY transitions. This eliminates voltage transients at the output pins, removing the need for external mute switches or timed GPIO control-verified across –40°C to +85°C operating range.

Can the DEMOTS488S drive 600 Ω professional headphones?

No-the TS488 is optimized for 16–100 Ω loads. At 600 Ω, output power drops to ~1.6 V_RMS (≈4.3 mW) with rising THD+N above 1% at mid-frequencies. Its output stage lacks the voltage swing and current capability required for high-impedance headphones; dedicated line drivers or op-amps are recommended instead.

What PCB layout practices maximize thermal performance in DFN8 package?

Maximize thermal performance by soldering the exposed pad (Pin 8) to a ≥25 mm² internal or bottom-layer copper pour connected via ≥4 thermal vias (0.3 mm diameter) to inner ground planes. Maintain ≥0.2 mm clearance around the pad edge and avoid silkscreen over the EP. ST specifies R_thJA = 40 °C/W on 4-layer boards with this layout.