The worker has to obey the stipulation specified in the working instruction of cell phone jammer
When the battery detection circuit fails, the general is the charging always charge or show the charging symbol but not the charge of failure. Motorola mobile phone charging circuit analysis and repair. Motorola V998 cell phone charger is connected through the phone the tailstock interface J600 and phone J600 of 5 feet (MAN-TEST) for the detection side of the rechargeable type, used to detect the charger quick charger or medium-speed charger, 8 of J600 feet (EXTCHG-EN) for charging the test side, used to detect the charger is plugged into charging the phone, the phone is charging 14-pin J600 for an external power supply EXT-B +, sent to the D10 side of the U900. The management of cell phone jammer will be much easier and more convenient.
And through the sampling resistor R932 (0.25 ohms) to the charge pipe Q932 4 feet and U900 U900 D9 (1SENSE) port. U900, depending on the size of the R932 resistance, calculate the charge current on the R932, compared the current and standard current output charge control signal to control the degree of conduction of Q932's, to further control the size of the charge current. When the the U900 F7 side (battery voltage BATT +) detected when the battery voltage is not saturated, and the phone with the external power supply cell phone jammer , the CPU control the the the U900 charging control side ElCHRGC output a low level, control Q932 start charging circuit, an external power supply by R932, Q932, and CR932 to charge the battery.
This signal is used to detect the charging voltage is too high, when the charging voltage is too high, this signal will pull low, central processing unit D300 is detected, immediately send the interrupt signal, the switch V205 N200 within The charge separation switch, stop charging the battery. As can be seen from the above, better protection measures for the Nokia 3310 mobile phone charging circuit, the circuit is slightly more complex. The following examples of the maintenance of the charging fault. Samsung mobile phone charging circuit analysis and repair cell phone jammer . The following Samsung A188, A288 mobile phone, for example. The A188 cell phone standby charging circuit to control the composition of modules of U605, U609, U607 and CPUU201 etc. charge.