LM4890MM/NOPB Texas Instruments 音频放大器 1 Watt Audio Pwr Amp

1FEATURES DESCRIPTION

2 The LM4890 is an audio power amplifier primarily • Available in Space-Saving Packages: DSBGA,

designed for demanding applications in mobile VSSOP, SOIC, and WSON

phones and other portable communication device

• Ultra Low Current Shutdown Mode applications. It is capable of delivering 1 watt of

• BTL Output Can Drive Capacitive Loads continuous average power to an 8Ω BTL load with

less than 1% distortion (THD+N) from a 5VDC power • Improved Pop & Click Circuitry Eliminates

supply. Noises During Turn-On and Turn-Off

Transitions Boomer audio power amplifiers were designed

• 2.2 - 5.5V Operation specifically to provide high quality output power with a

minimal amount of external components. The

• No Output Coupling Capacitors, Snubber LM4890 does not require output coupling capacitors Networks or Bootstrap Capacitors Required or bootstrap capacitors, and therefore is ideally suited

• Thermal Shutdown Protection for mobile phone and other low voltage applications

where minimal power consumption is a primary • Unity-Gain Stable

requirement.

• External Gain Configuration Capability

The LM4890 features a low-power consumption

APPLICATIONS shutdown mode, which is achieved by driving the

shutdown pin with logic low. Additionally, the LM4890

• Mobile Phones features an internal thermal shutdown protection

• PDAs mechanism.

• Portable Electronic Devices The LM4890 contains advanced pop & click circuitry

which eliminates noises which would otherwise occur

KEY SPECIFICATIONS during turn-on and turn-off transitions.

• PSRR at 217Hz, VDD = 5V (Fig. 1): 62dB(typ.) The LM4890 is unity-gain stable and can be

• Power Output at 5.0V & 1% THD: 1W(typ.) configured by external gain-setting resistors.

• Power Output at 3.3V & 1% THD: 400mW(typ.)

• Shutdown Current: 0.1μA(typ.)