Circuit Description
4-12
Samsung Electronics
When the battery is being charged, U23B becomes
high and the output voltage of U24A pin 2 returns
to the reference.
When the battery is fully charged, the battery
temperature is increased. After detecting the
temperature, if the U24A pin 2 is greater than pin
3, the output status of U23 and U24 are as follows:
OUT-A
OUT-B
Q21
Q20
U23
L
H
U24
L
H
OFF
OFF
When charging is completed, 20mA trickle current
flows through R24, R25, and D21. Q24 turns on,
and red LD1 turns off. Latch circuit operates so
that U24A remains in low and trickle current is
supplied to the battery. The latch is released when
AC power turns off or the battery is removed from
the main body.
Summary of Contents for SCH-1900
Page 2: ...Samsung Electronics Co Ltd GH68 60620A Printed in Korea ...
Page 27: ...Samsung Electronics 6 1 6 Troubleshooting 6 1 Logic Section 6 1 1 No Power ...
Page 29: ...Samsung Electronics 6 3 Troubleshooting 6 1 3 Abnormal Backlight Operation ...
Page 30: ...Troubleshooting 6 4 Samsung Electronics 6 1 4 Abnormal Key Data Input ...
Page 31: ...Samsung Electronics 6 5 Troubleshooting 6 1 5 Abnormal Keytone ...
Page 32: ...Troubleshooting 6 6 Samsung Electronics 6 1 6 Abnormal Alert Tone ...
Page 33: ...Samsung Electronics 6 7 Troubleshooting 6 2 Transmitter Section ...
Page 34: ...Troubleshooting 6 8 Samsung Electronics ...
Page 35: ...Troubleshooting 6 9 Samsung Electronics 6 3 Receiver Section ...
Page 36: ...Troubleshooting 6 10 Samsung Electronics ...
Page 37: ...Samsung Electronics 6 11 Troubleshooting ...
Page 39: ...Troubleshooting 6 13 Samsung Electronics 6 4 2 No Power HHP PWR 5 8V 13 5V Supply ...
Page 40: ...Samsung Electronics 6 14 Troubleshooting 6 4 3 Hands Free RX Path ...
Page 41: ...Troubleshooting 6 15 Samsung Electronics 6 4 4 Hands Free TX Path ...
Page 42: ...Samsung Electronics 6 16 Troubleshooting 6 5 Desk Top Rapid Charger ...
Page 43: ...Troubleshooting 6 17 Samsung Electronics 6 6 Cigarette Lighter Adapter 6 6 1 Power Fault ...
Page 44: ...Troubleshooting 6 18 Samsung Electronics 6 6 2 LED On Fault ...
Page 45: ...Troubleshooting 6 19 Samsung Electronics 6 6 3 Charge Fault ...
Page 46: ...Troubleshooting 6 20 Samsung Electronics 6 7 Travel Charger ...
Page 48: ...Exploded View and its Parts List 7 2 Samsung Electronics 7 1 Main Set Exploded View ...
Page 50: ...Exploded View and its Parts List 7 4 Samsung Electronics 7 3 Hands Free Kit Exploded View ...
Page 58: ...Exploded View and its Parts List 7 12 Samsung Electronics 7 11 Main Set Packing Layout ...
Page 60: ...7 14 Samsung Electronics Exploded View and its Parts List 7 13 Hands Free Kit Packing Layout ...
Page 62: ...7 16 Samsung Electronics Exploded View and its Parts List ...
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Page 100: ...10 2 Hands Free Kit Block Diagram ...
Page 101: ...10 3 Desk Top Rapid Charger Block Diagram ...
Page 102: ...10 4 Cigarette Lighter Adapter Block Diagram ...
Page 103: ...10 5 Travel Charger Block Diagram ...
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