The English Proceedings of the College of Instrumentation&Electrical Engineering.n University,in the Second Halfof 013 WM2 ig3DC/DC inverte leeds to be Charge The system ente standby mode End Fig4 System program flow chart 2.2 Charging subroutine design charge current will gradually be reduced to zero,the irst stage is the constant voltage charging.the charging voltage can be set,when the charging voltage charged,the"fully charged"indicator is lit green.As reaches 4.2V,is transferred to the second stage,that is the mobile phone's battery and charging distance are 4.2V constant voltage charging.constant voltage different,electricity charged into the mobile phone charging current will increase gradually decreased battery is different.The capacity of the ithum battery over time.until the charge curent drops to 10mA.i of Small wasps and HTCONEX are 1420mAh and indicates that the battery has been charged to the rated 2000mAh used in the experiment.For example,the capacity of 90%to 95%.At this point it can be third row of Table I:Lithium Output voltage 3.7v, considered basic full,if we continue to charge it,the transmitter terminal voltage and current of 12V and 4 期 The English Proceedings of the College of Instrumentation & Electrical Engineering, Jilin University, in the Second Half of 2013 4 AR1 LM358 R20 1K AD1 C5 0.1UF AD0 1 (+)1 2 (-)1 3 FB 4 DTC 5 CT 6 RT 7 GND 8 C1 10 E2 9 E1 C2 251 12 VCC 13 OC 14 RO 15 (-)2 16 (+)2 RP1 KA7500B T1 PNP R15 100 R3 510 D4 IN5819 L1 100uH C3 470uF C2 470uF USB+ USB￾R2 6.49k R18 10K R29 1K C9 0.1UF C10 0.01UF C13 0.01UF R34 10K R32 300 C11 3.3UF PWM1 PWM2 R22 590 R23 590 R30 20k C8 0.1UF 100K R21 R16 100k R24 R26 100k 1K +5V D2 SR260 R33 20K R25470 差分放大电路 RC滤波 RC滤波 RC滤波 R4 0.05 C4 0.1UF R5 10k Vin 1 GND 2 Vout 3 U1 LM2940 C1470uF +5 D1 LED R1 1K R28 10K R31 1K D3 SR260 90uH L2 USB 单片机电源 N2 N2 Fig.3 DC/DC inverter Fig.4 System program flow chart 2.2 Charging subroutine design Charging process is divided into two phases, the first stage is the constant voltage charging, the charging voltage can be set, when the charging voltage reaches 4.2V, is transferred to the second stage, that is 4.2V constant voltage charging, constant voltage charging current will increase gradually decreased over time, until the charge current drops to 10mA, it indicates that the battery has been charged to the rated capacity of 90% to 95%.At this point it can be considered basic full, if we continue to charge it, the charge current will gradually be reduced to zero, the battery is fully charged. Specific charging process, "charge" red light is lit; when the battery is fully charged, the "fully charged" indicator is lit green. As the mobile phone's battery and charging distance are different, electricity charged into the mobile phone battery is different. The capacity of the lithium battery of Small wasps and HTCONEX are 1420mAh and 2000mAh used in the experiment. For example, the third row of Table I: Lithium Output voltage 3.7v, transmitter terminal voltage and current of 12V and Start Initializatio Needs to be Charge monitoring The system enters standby mode End