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KX-FT982LS-B / KX-FT984LS-B / KX-FT988LS-B
6.3.5.
RTC Back up Circuit
1.
Function
This unit has a lithium battery (BAT1) which works for the Real Time Clock (RTC, Integrated into ASIC:IC1).
The RTC continues functioning, even when the power switch is OFF, backed up by a lithium battery.
2.
Circuit Operation
When the power is turned ON, power is supplied to RTC (IC1).
At this time, the voltage at pin 14 of RTC (IC1) is +3.3V. When the power is turned OFF, the battery supplies the power to RTC
through JS1, R30, D14. At that time, the voltage at pin 14 of IC1 are about +2.5V. When the power is OFF and the +5V and
+3.3V voltages decrease, the LOW is input to pin 114 of IC1. Pin 111 of IC1 outputs the reset signals. Pin 11 of IC1 become
low, then RTC (IC1) go into the back up mode, when the power consumption is lower.
Summary of Contents for KX-FT982LS-B
Page 2: ...2 KX FT982LS B KX FT984LS B KX FT988LS B ...
Page 12: ...12 KX FT982LS B KX FT984LS B KX FT988LS B 6 Technical Descriptions 6 1 Connection Diagram ...
Page 14: ...14 KX FT982LS B KX FT984LS B KX FT988LS B 6 2 1 General Block Diagram ...
Page 22: ...22 KX FT982LS B KX FT984LS B KX FT988LS B 6 4 2 Block Diagram ...
Page 24: ...24 KX FT982LS B KX FT984LS B KX FT988LS B ...
Page 72: ...72 KX FT982LS B KX FT984LS B KX FT988LS B Countermeasure ...
Page 73: ...73 KX FT982LS B KX FT984LS B KX FT988LS B REFERENCE Test Mode P 55 ...
Page 74: ...74 KX FT982LS B KX FT984LS B KX FT988LS B REFERENCE Test Mode P 55 ...
Page 75: ...75 KX FT982LS B KX FT984LS B KX FT988LS B REFERENCE Test Mode P 55 ...
Page 76: ...76 KX FT982LS B KX FT984LS B KX FT988LS B REFERENCE Test Mode P 55 ...
Page 77: ...77 KX FT982LS B KX FT984LS B KX FT988LS B ...
Page 78: ...78 KX FT982LS B KX FT984LS B KX FT988LS B ...
Page 79: ...79 KX FT982LS B KX FT984LS B KX FT988LS B REFERENCE Test Mode P 55 ...
Page 83: ...83 KX FT982LS B KX FT984LS B KX FT988LS B ...
Page 109: ...109 KX FT982LS B KX FT984LS B KX FT988LS B NG Wave pattern Note Refer to NG Example P 114 ...
Page 111: ...111 KX FT982LS B KX FT984LS B KX FT988LS B I O and Pin No Diagram ...
Page 114: ...114 KX FT982LS B KX FT984LS B KX FT988LS B 12 5 6 2 NG Example ...
Page 116: ...116 KX FT982LS B KX FT984LS B KX FT988LS B ...
Page 121: ...121 KX FT982LS B KX FT984LS B KX FT988LS B 12 5 9 2 Troubleshooting Flow Chart ...
Page 128: ...128 KX FT982LS B KX FT984LS B KX FT988LS B 13 Service Fixture Tools ...
Page 134: ...134 KX FT982LS B KX FT984LS B KX FT988LS B 14 2 2 How to Remove the P C Boards and Power Cord ...
Page 138: ...138 KX FT982LS B KX FT984LS B KX FT988LS B 14 3 3 How to Remove the Separation Rubber Flap ...
Page 139: ...139 KX FT982LS B KX FT984LS B KX FT988LS B 14 4 Installation Position of the Lead Wires ...
Page 140: ...140 KX FT982LS B KX FT984LS B KX FT988LS B ...
Page 148: ...148 KX FT982LS B KX FT984LS B KX FT988LS B 15 2 3 4 Copying REFERENCE Sensor Section P 124 ...
Page 153: ...153 KX FT982LS B KX FT984LS B KX FT988LS B 16 1 4 Power Supply Board ...
Page 155: ...155 KX FT982LS B KX FT984LS B KX FT988LS B 16 3 Test Chart 16 3 1 ITU T No 1 Test Chart ...
Page 156: ...156 KX FT982LS B KX FT984LS B KX FT988LS B 16 3 2 ITU T No 2 Test Chart ...
Page 157: ...157 KX FT982LS B KX FT984LS B KX FT988LS B MEMO ...
Page 170: ...170 KX FT982LS B KX FT984LS B KX FT988LS B MEMO ...
Page 180: ...180 KX FT982LS B KX FT984LS B KX FT988LS B 20 1 1 Operation Panel Section KX FT982 KX FT984 ...
Page 181: ...181 KX FT982LS B KX FT984LS B KX FT988LS B 20 1 2 Operation Panel Section KX FT988 ...
Page 182: ...182 KX FT982LS B KX FT984LS B KX FT988LS B 20 1 3 Upper Cabinet Section ...
Page 183: ...183 KX FT982LS B KX FT984LS B KX FT988LS B 20 1 4 Lower Cabinet Section ...
Page 184: ...184 KX FT982LS B KX FT984LS B KX FT988LS B 20 1 5 Gear Block Section ...
Page 185: ...185 KX FT982LS B KX FT984LS B KX FT988LS B 20 1 6 Screws ...
Page 186: ...186 KX FT982LS B KX FT984LS B KX FT988LS B 20 1 7 Accessories and Packing Materials ...