Circuit Detector and Disconnecting Over Voltage Schematic


Posted on Feb 4, 2014

The circuit in this figure is protecting the circuit and the system with power supplies that may exceed safe limits. One example is small consumer products that use external ac adapters; its easy to mistakenly plug in the wrong adapter. Another example is a portable system that uses a rechargeable battery pack. If the battery pack is absent or fai


Circuit Detector and Disconnecting Over Voltage Schematic
Click here to download the full size of the above Circuit.

ls to open during recharging, a high-compliance charger can deliver excessive voltages to the system. The circuit works using LM4041 adjustable shunt-voltage regulator as a voltage detector. When it operates as a reference, the LM4041 develops a voltage across its positive and negative terminals. This signal forces the voltage across R1 to equal 1. 24V. In this circuit, however, R3 prevents this servo action. With R3 in the circuit, VG is near ground when the voltage across R1 is less than 1. 24V, and VG is approximately 1V below the positive rail when the voltage across R1 is greater than 1. 24V. You can, therefore, set a threshold voltage by selecting appropriate values of R1 and R2. When the supply voltage exceeds the threshold, VG goes high, thereby turning off Q1 and removing power from the load. Select R1 and R2 according to: It where VSHUTOFF is the supply voltage that causes shutoff. With the values shown, the circuit removes power from the load when the supply voltage reaches approximately 6V. R4 provides hysteresis to prevent chattering when the supply voltage is near the shutoff value. IC1 can accommodate shutoff voltages as high as 10V; clamping IC1s supply voltage with another inexpensive shunt reference or zener diode (across the positive and negative terminals) allows higher maximum shutoff voltages. Maximum supply voltage with the components is approximately 50V.




Leave Comment

characters left:

New Circuits

.

 


Popular Circuits

DC Motor Controller
10Mhz universal counter
Tuch Sensitive Light Dimmer Circuit
lamp turning off prevention circuit of car
the water level control system design of the one-chip computer
wein bridge sine wave oscillator lm101
LED VU Meter by LM339 PCB
PS10NG Quad Power Sequencing Controller
TDA8920BTH 200 watts d class amplifier circuit diagram
5000W ultra-light high-power amplifier without switching-mode power supply
TDA1514 40 Watt Audio Amplifier Circuit
SCR Phase Control Speed Control/Dimmer
Fog Lamp Switch Circuit
Focusser
new pedal schematic



Top