Overview
The LM4675SDX/NOPB is a high-efficiency, mono Class D audio power amplifier produced by Texas Instruments. This device is designed to meet the demands of mobile phones and other portable communication devices. It operates on a single supply voltage ranging from 2.4V to 5.5V, making it highly versatile. The LM4675SDX/NOPB features a spread spectrum, filterless PWM architecture that reduces EMI-radiated emissions and eliminates the need for an output filter, thereby simplifying the design and reducing the external component count and board area consumption.
Key Specifications
| Parameter | Value | Parameter | Value |
|---|---|---|---|
| Audio input type | Analog Input | Architecture | Class-D |
| Speaker channels (max) | Mono | Rating | Catalog |
| Power stage supply (max) (V) | 5.5 | Power stage supply (min) (V) | 2.4 |
| Load (min) (Ω) | 4 | Output power (W) | 2.7 |
| SNR (dB) | 97 | THD + N at 1 kHz (%) | 0.03 |
| Iq (typ) (mA) | 2.8 | Control interface | Hardware |
| Closed/open loop | Open | Analog supply (min) (V) | 2.4 |
| Analog supply voltage (max) (V) | 5.5 | PSRR (dB) | 82 |
| Operating temperature range (°C) | -40 to 85 |
Key Features
- High Efficiency Operation: Achieves high efficiency with speaker loads, especially compared to typical Class AB amplifiers.
- Low Noise Amplification: Offers a high signal-to-noise ratio (SNR) of 97 dB and low total harmonic distortion plus noise (THD + N) of 0.03% at 1 kHz.
- Robust Overload Protection: Includes output short circuit and thermal overload protection to prevent device damage during fault conditions.
- Spread Spectrum Architecture: Reduces EMI-radiated emissions and eliminates the need for an output filter.
- Externally Configurable Gain: Allows independent gain control from multiple sources by summing the signals.
- Micro-Power Shutdown Mode: Features a low-power consumption shutdown mode, with a total shutdown power supply current of 0.01µA (typ).
- Fast Turn On Time: Very fast turn-on time of 17μs (typ).
- Minimum External Components: Simplifies design by reducing the external component count and board area consumption.
- 'Click and Pop' Suppression Circuitry: Reduces audible clicks and pops during power-up and power-down.
Applications
The LM4675SDX/NOPB is ideal for use in mobile phones, portable communication devices, and other handheld electronics where high efficiency, low noise, and minimal EMI are critical. Its compact package and low power consumption make it suitable for battery-powered devices.
Q & A
- What is the operating voltage range of the LM4675SDX/NOPB?
The LM4675SDX/NOPB operates on a single supply voltage ranging from 2.4V to 5.5V.
- What type of audio amplifier is the LM4675SDX/NOPB?
The LM4675SDX/NOPB is a mono Class D audio power amplifier.
- What is the maximum output power of the LM4675SDX/NOPB?
The maximum output power is 2.7W into a 4Ω load.
- Does the LM4675SDX/NOPB require an output filter?
No, the LM4675SDX/NOPB features a filterless PWM architecture that eliminates the need for an output filter.
- What is the signal-to-noise ratio (SNR) of the LM4675SDX/NOPB?
The SNR is 97 dB.
- What protection features does the LM4675SDX/NOPB have?
The device includes output short circuit and thermal overload protection.
- How does the LM4675SDX/NOPB reduce EMI?
The device uses a spread spectrum architecture to reduce EMI-radiated emissions.
- What is the typical quiescent current of the LM4675SDX/NOPB?
The typical quiescent current is 2.8 mA.
- What is the operating temperature range of the LM4675SDX/NOPB?
The operating temperature range is -40°C to 85°C.
- Does the LM4675SDX/NOPB have a shutdown mode?
