3544

UNISONIC TECHNOLOGIES CO., LTD 3544 LINEAR INTEGRATED CIRCUIT HEADPHONE AMPLIFIER FOR CD-ROMS  DESCRIPTION As a dual headphone amplifier the UTC 3544 is digital-source. The UTC 3544 has a steady gain of 6dB and so it is unnecessary for external gain setting. The UTC 3544 has internal mute function so that it is greatly simplified for prevention of the popping sound when power is turned on and off. To prevent damage from short circuits the UTC 3544 is equipped with thermal shutdown circuit.  FEATURES * Internal mute function to prevent popping sounds when *the power is turned on and off. * Built-in thermal shutdown circuit (150°C) to prevent *damage to the IC if a short circuit occurs. ■ ORDERING INFORMATION Ordering Number Lead Free Halogen Free 3544L-D08-T 3544G-D08-T - 3544G-S08-R Package DIP-8 SOP-8 Packing Tube Tape Reel  MARKING DIP-8 SOP-8 www.unisonic.com.tw Copyright © 2015 Unisonic Technologies Co., Ltd 1 of 9 QW-R107-040.D 3544  PIN DESCRIPTIONS PIN NO. PIN NAME I/O PIN VOLTAGE 1 OUT1 O 2.1V 7 OUT2 O 2.1V (VCC=5V) LINEAR INTEGRATED CIRCUIT INTERNAL EQUIVALENT CIRCUIT Vcc FUNCTION 1 7 10k Output pin 2 MUTE I 0.1V (When open) Mute control pin (set to low for prevention of popping noise when power is turned on and off). Operating: High Muting: Low(open) 3 IN1 I 2.1V 5 IN2 I 2.1V (VCC=5V) 6 BIAS I/O 2.1V (VCC=5V) 4 GND I 8 VCC I Input pin Bias pin (the external 47μF capacitor also serves as the anti-pop time c...