Ultra low power stereo headphone amplifier with capacitor-less output

The TS4909 is a stereo audio amplifier designed to drive headphones in portable applications. The integrated phantom ground is a circuit topology that eliminates the heavy output coupling capacitors. This is of primary importance in portable applications where space constraints are very high. A single-ended configuration is also available, offering even lower power consumption because the phantom ground can be switched off. Pop-and-click noise during switch-on and switch-off phases is eliminated by integrated circuitry.

Specially designed for applications requiring low power supplies, the TS4909 is capable of delivering 31 mW of continuous average power into a 32 Ω load with less than 1% THD+N from a 3 V power supply. Featuring an active low standby mode, the TS4909 reduces the supply current to only 10 nA (typ.). The TS4909 is unity gain stable and can be configured by external gain-setting resistors.

Key Features

  • No output coupling capacitors necessary
  • Pop-and-click noise reduction circuitry
  • Operating from VCC = 2.2 V to 5.5 V
  • Standby mode active low
  • Output power:
    • 158 mW at 5 V, into 16 Ω with 1% THD+N max (1 kHz)
    • 52 mW at 3.0 V into 16 Ω with 1% THD+N max (1 kHz)
  • Ultra-low current consumption: 2.0 mA typ. at 3 V
  • Ultra-low standby consumption: 10 nA typ.
  • High signal-to-noise ratio: 105 dB typ. at 5 V
  • High crosstalk immunity: 110 dB (F = 1 kHz) for single-ended outputs
  • PSRR: 72 dB (F = 1 kHz), inputs grounded, for phantom ground outputs
  • Low tWU : 50 ms in PG mode, 100 ms in SE mode
  • Available in lead-free DFN10 3 x 3 mm


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Description バージョン サイズ
DS4580 DS4580: Dual mode low power 150 mW stereo headphone amplifier with capacitor-less and single-ended outputs 9.0 581 KB
Description バージョン サイズ
AN2622 AN2622: TS4909 low power stereo headphone amplifier evaluation board user guidelines 1.2 105 KB

Publications and Collaterals

Description バージョン サイズ
ST’s solutions for mobile devices 3.2 2 MB
サポート & コミュニティ

サンプル & 購入

製品型番 パッケージ Packing Type Operating Temperature (°C) (min) Operating Temperature (°C) (max) Marketing Status Unit Price (US$) * 数量 ECCN (EU) ECCN (US) Country of Origin More info Order from ST Order from Distributors
TS4909IQT VDFPN 10 3x3x1.0 Tape And Reel -40 85 Active 0.454 1000 NEC EAR99 MALAYSIA MORE INFO DISTRIBUTOR AVAILABILITY

(*) Suggested Resale Price per unit (USD) for BUDGETARY USE ONLY. For quotes, prices in local currency, please contact your local ST Sales Office  or our Distributors

品質 & 信頼性

製品型番 Marketing Status パッケージ Grade RoHS Compliance Grade Material Declaration**
TS4909IQT アクティブVDFPN 10 3x3x1.0IndustrialEcopack1

(**) The Material Declaration forms available on st.com may be generic documents based on the most commonly used package within a package family. For this reason, they may not be 100% accurate for a specific device. Please contact our sales support for information on specific devices.