Overview
The TPA6138A2PWR, produced by Texas Instruments, is a 40-mW, stereo, analog input headphone amplifier designed with adjustable gain and several advanced features. This device utilizes TI’s patented DirectPath™ technology, which allows for the removal of output DC-blocking capacitors, reducing component count and board area. It is particularly suited for applications requiring low noise, high signal-to-noise ratio (SNR), and dynamic range, making it ideal for various audio systems.
Key Specifications
| Parameter | Value |
|---|---|
| Output Power | 40 mW into 32 Ω with 3.3-V supply |
| Gain Range | ±1 V/V to ±10 V/V (adjustable by external resistors) |
| Input Type | Differential input, single-ended output |
| Supply Voltage | 3.3 V |
| THD+N | 0.01% at 1 kHz, 10 mW into 32 Ω |
| SNR | 90 dB (A-weighted) |
| Dynamic Range | 100 dB (A-weighted) |
| Noise Voltage | 13 μV (A-weighted) |
| Output Impedance (Muted) | 110 mΩ |
| Input-to-Output Attenuation (Muted) | 80 dB |
| Crosstalk | -75 dB |
| Current Limit | 50 mA |
| ESD Protection | ±8-kV IEC |
Key Features
- Adjustable Gain: Gain can be adjusted from ±1 V/V to ±10 V/V using external resistors.
- DirectPath™ Technology: Eliminates the need for output DC-blocking capacitors, reducing component count and board area.
- Low Noise and THD: High SNR and low THD+N ensure high-quality audio output.
- Active-Mute Control: Built-in active-mute control for easy muting of the audio output.
- Configurable Low-Pass Filter: Can be configured as a second-order low-pass filter.
- Ideal for PWM Audio Sources: Suitable for interfacing with PWM audio sources.
Applications
The TPA6138A2PWR is ideal for various audio applications, including portable audio devices, smartphones, tablets, and other consumer electronics that require high-quality audio output with low noise and high dynamic range. It is also suitable for use in automotive audio systems and other environments where PWM audio sources are common.
Q & A
- What is the maximum output power of the TPA6138A2PWR? The maximum output power is 40 mW into a 32-Ω load with a 3.3-V supply.
- How is the gain adjusted in the TPA6138A2PWR? The gain can be adjusted from ±1 V/V to ±10 V/V using external gain-setting resistors.
- What is the DirectPath™ technology used in the TPA6138A2PWR? DirectPath™ technology eliminates the need for output DC-blocking capacitors, reducing component count and board area.
- What are the key noise specifications of the TPA6138A2PWR? The device has a THD+N of 0.01%, SNR of 90 dB (A-weighted), and a noise voltage of 13 μV (A-weighted).
- Does the TPA6138A2PWR have built-in ESD protection? Yes, it has ±8-kV IEC ESD protection.
- Can the TPA6138A2PWR be configured as a low-pass filter? Yes, it can be configured as a second-order low-pass filter.
- What is the current limit of the TPA6138A2PWR? The current limit is 50 mA.
- Is the TPA6138A2PWR suitable for PWM audio sources? Yes, it is ideal for interfacing with PWM audio sources.
- How does the active-mute control work in the TPA6138A2PWR? The device has built-in active-mute control, which can be activated by setting the mute pin low.
- What is the output impedance when the TPA6138A2PWR is muted? The output impedance when muted is 110 mΩ.
