Circuit extends battery life

摘要

Two previous Design Ideas describe simple ways to automatically disconnect a battery from its load after a preset on period, which extends battery life (references 1 and 2). These circuits have little loss in standby operation, but they do draw some current. The circuit in this Design Idea presents a simpler way to perform the same function with fewer components and with no power consumption during standby operation (Figure 1). Moreover, the network comprising R_2, D_2, and C_2 activates and deactivates the circuit. An additional control signal, control on/off, becomes slower than the battery's on/ off cycle.