SGS-THOMSON company introduced three single-chip Class D amplifier IC, they were TDA7480 (10W), TDA 7481C (18W) and TDA7482 (25W). In this paper, to the greatest power output TDA7482 be introduced as an example.
TDA7482 TDA7482 is audio with Class D amplifier PWM monolithic IC. This series of IC design for high-efficiency occasions such as large-screen color TV's sound system and home stereo devices.
TDA7482 for the main technical parameters:
(1) 25 W rated output power. Working conditions are: RL = 4 ~ 8 Ω, THD ≤ 10%. In fact, in accordance with the recommendation of the parameters, when RL = 8 Ω, P out = 1 W at its THD is only 0.1 percent.
(2) has a high output efficiency. When Vcc = ± 21V, RL = 8 Ω, P out = 18 W, the efficiency of 78 percent, so only a small work of the radiator, or even do not have to be.
(3) wide operating voltage range. Recommended for ± 10V ~ ± 25V, a car battery for power supply.
(4) are equipped with overcurrent protection devices, when RL = 0 Ω at the threshold for action to protect 3.5 A ~ 5A.
(5) are equipped with over-voltage protection devices, the threshold for the protection of 50 V.
(6) overheated overload, overheated temperature close to 150 ℃.
(7) ST-BY and MUTE functions.
(8) recommended the carrier frequency PWM operating frequency is 100 kHz ~ 200kHz.
(9) input noise (20 Hz ~ 20kHz) for 7 μ F ~ 12 μ F.
(10) input impedance for the 30 k Ω.
(11) Maximum power 3.8 W.
TDA7482 typical application circuit, as shown below
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