Overview
The LM4991LD/NOPB from Texas Instruments is a high-performance, single-channel, Class-AB audio power amplifier. It is part of the Boomer series and is designed to deliver high-fidelity audio output with minimal distortion. This amplifier is capable of delivering 3W of continuous average power into a 3Ω load with less than 10% Total Harmonic Distortion (THD) when powered by a 5V supply. The LM4991LD/NOPB operates on low supply voltages ranging from 2.2V to 5.5V, making it ideal for low-power portable systems that require minimal volume and weight.
Key Specifications
| Parameter | Value | Parameter | Value |
|---|---|---|---|
| Manufacturer | Texas Instruments | Series | LM4991 |
| Product | Audio Amplifiers | Class | Class-AB |
| Output Power | 3 W (into 3Ω), 1.5 W (into 8Ω) | Mounting Style | SMD/SMT |
| Type | 1-Channel Mono | Audio - Load Impedance | 3 Ohms, 8 Ohms |
| THD plus Noise | 0.2 % | Supply Voltage - Max | 5.5 V |
| Supply Voltage - Min | 2.2 V | Minimum Operating Temperature | -40°C |
| Maximum Operating Temperature | +85°C | Operating Supply Current | 4 mA |
| PSRR - Power Supply Rejection Ratio | 64 dB | Shutdown Current | 0.1µA (typ) |
| Package / Case | 8-WDFN Exposed Pad | Number of Pins | 8 |
| Moisture Sensitivity Level (MSL) | 3 (168 Hours) | Bandwidth | 20 kHz |
Key Features
- Ultra Low Current Shutdown Mode: Consumes only 0.1µA (typ) when activated, ideal for power conservation in portable devices.
- Improved Audio Quality: Delivers crisp, clear audio with minimal distortion.
- No External Components Required: Does not require output coupling capacitors, bootstrap capacitors, or snubber networks.
- Unity-Gain Stable: Ensures stable operation without the need for additional gain-setting resistors.
- Thermal Shutdown Protection: Protects the device from overheating.
- Improved Click and Pop Circuitry: Reduces noises during turn-on and turn-off transitions.
- Low Power Consumption: Operates on low supply voltages from 2.2V to 5.5V.
- High PSRR: Power Supply Rejection Ratio of 64 dB at 217kHz and 1kHz.
Applications
- Wireless and Cellular Handsets: Ideal for portable communication devices due to its low power consumption and high audio quality.
- PDAs and Portable Computers: Suitable for personal digital assistants and portable computers where space and power efficiency are crucial.
- Desktop Computers: Can be used in desktop applications where high-fidelity audio output is required.
- Other Portable Devices: Applicable in various other portable electronic devices that require high-quality audio output with minimal power consumption.
Q & A
- What is the maximum output power of the LM4991LD/NOPB?
The LM4991LD/NOPB can deliver up to 3W of continuous average power into a 3Ω load and 1.5W into an 8Ω load at 10% THD.
- What is the operating voltage range of the LM4991LD/NOPB?
The operating voltage range is from 2.2V to 5.5V.
- What is the typical shutdown current of the LM4991LD/NOPB?
The typical shutdown current is 0.1µA.
- Does the LM4991LD/NOPB require external components like output coupling capacitors or snubber networks?
No, it does not require these external components.
- What is the Power Supply Rejection Ratio (PSRR) of the LM4991LD/NOPB?
The PSRR is 64 dB at 217kHz and 1kHz.
- What is the bandwidth of the LM4991LD/NOPB?
The bandwidth is 20 kHz.
- Is the LM4991LD/NOPB RoHS compliant?
Yes, it is RoHS compliant.
- What is the moisture sensitivity level (MSL) of the LM4991LD/NOPB?
The MSL is 3 (168 Hours).
- What kind of thermal protection does the LM4991LD/NOPB have?
The device has thermal shutdown protection.
- What are some common applications of the LM4991LD/NOPB?
Common applications include wireless and cellular handsets, PDAs, portable computers, and other portable electronic devices.
