Mobile Phone Battery Repair Instrument Design and Application(b)
Charge phase of our relationship with the general charger and different frequencies are used by cyclical changes in the pulse signal to the rechargeable batteries. Mainly taking into account the pulse signal can be hp laptop battery chemicals gradually activated, the battery factory to achieve results. Similarly, when they should not charge more than the termination value of charging voltage, over-charging of the battery may cause permanent damage.
Third, the production process
(A) discharge circuit design
1, the design requirements
① the general desirability of the hp ev087aa, hp ex942aa battery discharge current of 0.2 times the rated capacity.
② must accurately grasp the discharge termination voltage, so as to avoid over discharge the battery and injury.
③ manually conducted on discharge Kai, stop control.
2, the design features of
① battery discharge voltage to the termination should be automatically disconnected loop or automatic discharge into state-of-charge.
② facilitate hp pavilion zt3000, hp 337607-001 discharge monitoring job status.
Following discharge circuit design concept map:
Discharge circuit
Driver circuit may be part of two relays form a self-locking circuit, the discharge end of the disconnect switch automatically transferred to the charging part.
(B) charging circuit design
1, the design of indicators
① adjustable constant-current charge, maximum charge current 500mA.
②Over discharge automatically into a state of constant-current charge.
③ charge to end-of-charge voltage, constant current circuit to stop working, and lock in "Charging The End" state.
2, the design hp 337607-003, dg103a features of
① the use of voltage comparators to monitor the battery voltage, to ensure that end-of-charge voltage when the charge current and timely turn-off and lock in "Charging The End" state.
② automatic and manual features Kai, both stop function.
Charging circuit with the pulse signal combining circuit for charging. The 555 timer pulse signal can be used to achieve, with 3 555 to constitute a frequency change in the cycle pulse signal. Circuit diagram in Figure.
Required to connect the entire circuit has a logical relationship which can be used with the door to non-implementation, in the design, we have adopted a 4012 four door 398876-001, pb992a with non-phase input.