Harman Kardon AVR 2600, Руководство по обслуживанию

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SI-8005Q
Description
The SI-8005Q is a step-down switching regulator IC, designed as
an output voltage regulator at the secondary stage of switch mode
power supplies. The current-mode control system permits small
ceramic capacitors to be used as output capacitors. Together
with the compact HSOP8 package, this allows reduction of
regulator circuitry area on the PCB by approximately 50% in
comparison with conventional topologies.
Designed to save power, losses in the SI-8005Q are reduced
by controlling the maximum on-resistance of a built-in output
MOSFET to as low as 165 m . Furthermore, die miniaturization
has been accomplished through a proprietary BCD process.
The SI-8005Q supplies an output current of 3.5 A and an output
voltage that is variable from 0.5 to 24 V, which is easily set to
a voltage compatible with the diverse reduced power supply
voltages required by signal processing ICs. Accepting a wide
input voltage range, from 4.75 to 28 V, the SI-8005Q can be
driven directly by a 24 V power supply.
Applications include power supplies for signal processing ICs
for memories and microcomputers used in plasma display panel
(PDP) TVs, liquid crystal display (LCD) TVs, computer hard
drives, and DVD recorders.
Features and Benefits
Current-mode control system employed
Excellent line regulation (60 mV maximum)
165 m maximum on-resistance of built-in MOSFET
Output current 3.5 A
Wide range of input voltages (4.75 to 28 V), supports
24 V direct drive
Output voltage 0.5 to 24 V, compatible with various IC
power supply voltages, through low V
REF
of 0.5 V.
High efficiency, 94% maximum at V
IN
= 8 V, V
O
= 5 V,
and I
O
= 0.5 A
Operating frequency 500 kHz, supports downsizing of
smoothing choke coil
Soft start and output on/off functions built-in
Built-in protection:
Drooping overcurrent protection
Overtemperature protection
Undervoltage lockout (UVLO)
Step-Down Switching Regulator with Current-Mode Control
Functional Block Diagram
Not to scale
Package: HSOP8 surface mount with
exposed thermal pad
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27469.058, Rev. 1
AVR3600
harman/kardon
213