Overview
The TDA7381 is a class AB audio power amplifier designed by STMicroelectronics, specifically tailored for car radio applications. It is packaged in the Flexiwatt25 format, which allows for a compact and efficient design. This amplifier is known for its high output power capability, low distortion, and low output noise, making it an ideal choice for automotive audio systems.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Operating Supply Voltage (VCC) | 18 | V |
| Peak Supply Voltage (VCC pk) | 50 | V (t = 50 ms) |
| Max Output Power (Po max) | 30 | W (THD = 10%, VS = 13.7 V) |
| Max Power Dissipation (Ptot) | 80 | W (Tcase = 70 °C) |
| Junction Temperature (Tj) | 150 | °C |
| Storage Temperature (Tstg) | -40 to 150 | °C |
| Voltage Gain (Gv) | 26 | dB |
| Output Offset Voltage (VOS) | 100 | mV |
| Quiescent Current (Iq1) | 180-300 | mA |
Key Features
- High output power capability: up to 4 x 30 W/4 Ω max.
- Low distortion and low output noise.
- Standby and mute functions with CMOS-compatible inputs.
- Automute at minimum supply voltage detection.
- Diagnostics facility for clipping, output short circuits, and thermal shutdown.
- Low external component count with internally fixed gain (26 dB) and no external compensation or bootstrap capacitors.
- Protections include output short circuit to GND, to VS, across the load, very inductive loads, overrating chip temperature with soft thermal limiter, load dump voltage, fortuitous open GND, reversed battery, and ESD protection.
- Ground-compatible inputs that can handle high input signals (± 8 Vpk) without performance degradation.
Applications
The TDA7381 is primarily designed for car radio applications, offering high performance and reliability in automotive audio systems. Its features make it suitable for a variety of in-car entertainment systems, including radios, CD players, and other audio equipment.
Q & A
- What is the maximum output power of the TDA7381?
The TDA7381 can deliver up to 4 x 30 W/4 Ω max. output power at THD = 10% and VS = 13.7 V.
- What is the operating supply voltage range for the TDA7381?
The operating supply voltage for the TDA7381 is up to 18 V, with a peak supply voltage of 50 V for 50 ms.
- Does the TDA7381 have built-in protection features?
Yes, the TDA7381 includes protections such as output short circuit to GND, to VS, across the load, very inductive loads, overrating chip temperature with soft thermal limiter, load dump voltage, fortuitous open GND, reversed battery, and ESD protection.
- What is the voltage gain of the TDA7381?
The voltage gain of the TDA7381 is internally fixed at 26 dB.
- Does the TDA7381 require external compensation or bootstrap capacitors?
No, the TDA7381 does not require external compensation or bootstrap capacitors due to its fully complementary PNP/NPN output configuration).
- What diagnostics facilities are available on the TDA7381?
The TDA7381 has diagnostics facilities for detecting clipping, output short circuits to GND or VS, and thermal shutdown proximity).
- How does the standby and mute function work on the TDA7381?
The standby and mute functions are CMOS-compatible and can be controlled using conventional low-power transistors or microprocessors. The functions help in managing power consumption and audio output).
- What is the significance of the SVR capacitor in the TDA7381 circuit?
The SVR (Supply Voltage Rejection) capacitor is crucial for ensuring proper operation, high supply voltage rejection, and optimizing pop during ON/OFF transients. It should have a minimum recommended value of 10 μF).
- How should the AC-GND capacitor be connected in the TDA7381 circuit?
The AC-GND capacitor should be connected to the signal GND as close as possible to the audio inputs ground to ensure high rejection of common mode spurious signals).
- What are the thermal considerations for the TDA7381?
The TDA7381 has a junction temperature limit of 150°C and a thermal resistance junction to case of 1°C/W. It also features a soft thermal limiter to manage overrating chip temperature).
