Efficient Voltage Stabilizer for Battery-Powered Devices. Circuit Design Voltage stabilizers used in standalone battery-powered devices should consume as little power as possible. When we use line stabilizers, we need to consider the main requirements: the minimum allowable voltage drop on the stabilizer and the consumption current of the voltage stabilizer, which should not exceed several milliamperes. There are plenty of foreign stabilizers that meet these requirements. For now they are rather expensive and come in packages that are not so universal and often require soldering equipment for mounting. If we use such stabilizers as the LM317 or LT1084, the outcome is not so great -- the voltage drop on such stabilizers is about 1.5V. So we are left with only 1 option -- we will build a stabilizer using discrete components. Let's exemplify some of them. The stabilization factor if this stabilizer is 30 to 50. The output voltage of the stabilizer is determined by the ratio, where the output voltage is equal to the difference between the stabilization voltage of the voltage reference diode and the voltage drop at the emitter-based junction of VT2 transistor. The resulting value is added to the voltage drop on VD3 diode in direct connection. Here we can say that the output voltage is equal to the stabilization voltage of the voltage reference diode. We can improve the circuit parameters by replacing the voltage reference diode with the IC stabilizer KR142EN19. The stabilization factor at the output voltage of 3.4 would be equal to about 100. The minimum allowable voltage drop that depends upon the parameters of the VT1 would constitute 0.4 to 0.6V. The consumption current is determined entirely based upon the current flowing through the DA1, and, depending on the input voltage, would amount to 1-2mA.
