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Circuit Description
4-6
Samsung Electronics
4-4 Hands-Free Kit
Hands free board is largely composed of car
adapter circuit and Hands free circuit.
4-4-1 Car Adapter Circuit
POWER SUPPLY
Input power switching circuit : This circuit
includes Short protection circuit, and Power
switching control circuit. It supplies power for
HHP and hands free kit.
+13.5V switching circuit (Q801, 802) : This circuit
switches power for power amplifier using MPU
mute signal.
HHP power circuit : This circuit is Switching
regulator. Input voltage is +13.6v, output voltage
is +5.8v.
Vcc regulator (U704) : This circuit regulates Vcc
(+5V).
CHARGER CIRCUIT
This circuit charges battery pack by detecting the
temperature of battery, the slope of temperature,
the slope of the voltage of battery, and charging
time, etc.
During charging, the charger LED turn on red.
When charging is completed, the charger LED
turns on green.
Voltage detection circuit : Charging circuit is
designed to stop charging when the voltage of
battery is dropped.
The voltage of battery is entered to A/D converter
located in U703 #2.
Temperature detection circuit : The temperature
of battery is measured by missing NTC thermistor.
NTC themistor has a characteristics of Log-scale. It
obtains a linear characteristics by the parallel
connection of resistors.
4-4-2 Hands Free Circuit
POWER SUPPLY (U704,U808)
+5V is regulated by U704 for hands free circuit,
and -5V is regulated by U808.
TX PATH
The audio signal from external mic(JP705) flows
into U802 pin #11. U802 includes Amplifier and
Control circuit for hands free operatin. U801A
amplifies input signal. Output signal is
transmitted to HHP.
RX PATH
Input audio signal cancels noise by difference
amplifier (U801c). U802 performs hands free
action. The RX audio signal is input (U805). The
speaker drive amp (U804) amplifies the Rx audio
signal and the output of U804 goes out of speaker.
Battery Type
Capacity
Charge Current Charge Voltage
S t a n d a r d
8 5 0 m A H
3 0 0 m A
6 . 2 V
E x t e n d e d
1 5 0 0 m A H
6 0 0 m A
6 . 7 V
Summary of Contents for SCH-1000
Page 2: ...Samsung Electronics Co Ltd GH68 60563A Printed in Korea ...
Page 31: ...Samsung Electronics 6 1 6 Troubleshooting 6 1 Logic Section 6 1 1 No Power ...
Page 33: ...Samsung Electronics 6 3 Troubleshooting 6 1 3 Abnormal Backlight Operation ...
Page 34: ...Troubleshooting 6 4 Samsung Electronics 6 1 4 Abnormal Key Data Input ...
Page 35: ...Samsung Electronics 6 5 Troubleshooting 6 1 5 Abnormal Keytone ...
Page 36: ...Troubleshooting 6 6 Samsung Electronics 6 1 6 Abnormal Alert Tone ...
Page 37: ...Samsung Electronics 6 7 Troubleshooting 6 2 Transmitter Section ...
Page 38: ...Troubleshooting 6 8 Samsung Electronics ...
Page 39: ...Troubleshooting 6 9 Samsung Electronics 6 3 Receiver Section ...
Page 40: ...Troubleshooting 6 10 Samsung Electronics ...
Page 41: ...Samsung Electronics 6 11 Troubleshooting ...
Page 43: ...Troubleshooting 6 13 Samsung Electronics 6 4 2 No Power HHP PWR 5 8V 13 5V Supply ...
Page 44: ...Samsung Electronics 6 14 Troubleshooting 6 4 3 Hands Free RX Path ...
Page 45: ...Troubleshooting 6 15 Samsung Electronics 6 4 4 Hands Free TX Path ...
Page 46: ...Samsung Electronics 6 16 Troubleshooting 6 5 Desk Top Rapid Charger ...
Page 47: ...Troubleshooting 6 17 Samsung Electronics 6 6 Cigarette Lighter Adapter 6 6 1 Power Fault ...
Page 48: ...Troubleshooting 6 18 Samsung Electronics 6 6 2 LED On Fault ...
Page 49: ...Troubleshooting 6 19 Samsung Electronics 6 6 3 Charge Fault ...
Page 50: ...Troubleshooting 6 20 Samsung Electronics 6 7 Travel Charger ...
Page 52: ...Exploded View and its Parts List 7 2 Samsung Electronics 7 1 Main Set Exploded View ...
Page 54: ...Exploded View and its Parts List 7 4 Samsung Electronics 7 3 Hands Free Kit Exploded View ...
Page 62: ...Exploded View and its Parts List 7 12 Samsung Electronics 7 11 Main Set Packing Layout ...
Page 64: ...7 14 Samsung Electronics Exploded View and its Parts List 7 13 Hands Free Kit Packing Layout ...
Page 66: ...7 16 Samsung Electronics Exploded View and its Parts List ...
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