Hitachi C28W440N, Service Manual

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16.6.
74HCT32 ( For audio switching in multiple audio input models )
The 74HC/HCT32 are high-speed Si-gate CMOS devices and are pin compatible with low power Schottky
TTL (LSTTL). They are specified in compliance with JEDEC. The 74HC/HCT32 provide the 2-input OR
function.Used for audio switching purposes.
16.6.1.
Pinning
1, 4, 9, 12 : 1A to 4A data inputs
2, 5, 10, 13 : 1B to 4B data inputs
3, 6, 8, 11 : 1Y to 4Y data outputs
7 : GND ground (0 V)
14 : V
CC
positive supply voltage
For HC the condition is V
I
= GND to V
CC
For HCT the condition is V
I
= GND to V
CC
? ? 1.5 V
16.7.
MC44608
16.7.1.
General Description:
The MC44608 is a high performance voltage mode controller designed for off–line converters. This
high voltage circuit that integrates the start–up current source and the oscillator capacitor, requires few
external components while offering a high flexibility and reliability.
The device also features a very high efficiency stand–by management consisting of an effective Pulsed Mode
operation. This technique enables the reduction of the stand–by power consumption to approximately 1W while
delivering 300mW in a 150W SMPS.
• Integrated start–up current source
• Lossless off–line start–up
• Direct off–line operation
• Fast start–up
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