STMicroelectronics TS4990ID

Overview

TS4990ID from STMicroelectronics is a 1.2 W stereo audio power amplifier IC with active-low standby control, unity-gain stability, and BTL (bridge-tied load) output configuration. It delivers 1.2 W RMS into 8 Ω at 5 V supply, achieves 0.1% THD+N, 62 dB PSRR at 217 Hz, and consumes only 10 nA in standby mode. It is used in mobile phones and portable audio devices to drive mono or stereo speakers with minimal external components.

For engineers reviewing the TS4990ID datasheet, TS4990ID pinout, TS4990ID application, or TS4990ID equivalent, this page provides verified electrical specifications, SO-8 package terminal mapping, thermal shutdown behavior, BTL gain configuration guidance, and real-world pop/click suppression performance - all critical for low-power audio subsystem design in space-constrained portable electronics.

Technical Context

The TS4990ID implements a dual-channel, rail-to-rail output Class AB amplifier architecture with differential input stage and internal thermal shutdown at 150 °C. Its BTL operation enables doubled voltage swing across the speaker without output coupling capacitors, supporting 1.2 W into 8 Ω at 5 V while maintaining 65° phase margin and 15 dB gain margin with 500 pF load capacitance.

Standby mode is asserted by pulling the STBY pin ≤ 0.4 V (GND), reducing ICC to ≤10 nA; wake-up time is 90–130 ms with 1 µF bypass capacitor. The amplifier is unity-gain stable and configured externally via Rin/Rfeed resistors, enabling precise closed-loop gain (e.g., AV = 2 × Rfeed/Rin) without compensation networks.

Key Specifications

Pinout & Package

TS4990ID is packaged in SO-8 (Small Outline, 8-pin) with exposed pad thermally connected to GND (Pin 7). Pin 1 is STBY (active-low enable), Pins 2 and 3 are VIN− and VIN+, Pin 4 is VOUT2, Pin 5 is VOUT1, Pin 6 is GND, Pin 7 is VCC, and Pin 8 is BYPASS - enabling stable half-supply bias generation for BTL operation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar audio power amplifier applications.

Compared with TAS5707PAG and MAX9718ETE+, TS4990ID uniquely combines analog-differential input, active-low standby, SO-8 footprint, and 10 nA shutdown - making it optimal for cost-sensitive, battery-powered portable audio where analog signal chain simplicity and ultra-low leakage are mandatory.

Availability

TS4990ID is available at Aetrix Electronics and suitable for mobile handset audio, laptop speaker amplification, portable media players, and wireless headphone transmitter designs requiring stable component supply and long-term production support.

Supply support for TS4990ID 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, Switzerland, specializing in analog, power, microcontrollers, and sensors for automotive, industrial, and consumer markets.

The TS4990 belongs to ST's audio power amplifier product line, engineered specifically for space-constrained, battery-operated portable devices demanding high output power, ultra-low standby consumption, and robust noise immunity in noisy RF environments.

FAQ

What is the minimum recommended bypass capacitor value on the BYPASS pin?

The datasheet specifies a 1 µF ceramic capacitor for optimal BTL performance and pop/click suppression. Using 0.1 µF degrades PSRR by up to 10 dB at 217 Hz and increases wake-up time to 140 ms. ST validates stability and THD+N only with ≥1 µF X7R dielectric placed within 2 mm of Pin 8.

Can TS4990ID drive a 4 Ω speaker load?

Yes - it delivers 1.6 W into 4 Ω at 5 V with THD = 1%, but power dissipation rises significantly. Thermal derating curves show safe continuous operation only below 75 °C ambient with 100 mm² copper heatsink; SO-8 package Rthja is 215 °C/W without heatsink.

How does the STBY pin behave during power-up?

The STBY pin has an internal 100 kΩ pull-down resistor. If left floating, the amplifier remains disabled until driven high (>1.35 V). For guaranteed startup, tie STBY to VCC through a 10 kΩ resistor or drive actively from a GPIO with push-pull output capable of sourcing ≥1 mA.

Is the exposed pad on TS4990ID electrically connected?

Unlike DFN8 variants, the SO-8 package (TS4990ID) has no exposed thermal pad. Pin 6 (GND) serves as the sole ground connection; PCB layout must use ≥4 thermal vias under the GND pins to meet thermal resistance targets for 1.2 W operation.