Voltage Controlled Power Supply Tester by OPA277
While testing the power supplies or discovering their potential problems, you must apply dynamic and static tests. This circuit, namely current sink, makes this job easier for you. It can draw 0 to 1.5A current from the load depending on the input voltage between 0 to 5V applied to the input. The two main components of the circuit are OPA277 and IRF530 . OPA277 is a precision operational amplifier IC which features a max. V IO = 100 µV and I IB =4 nA. It makes a comparison between the voltage applied to its non-inverting terminal and the voltage across the resistor R SENSE . The second is the STMicroelectronics' IR530 N-Channel Power MOSFET which is capable of delivering max. 14 A with V DS voltage of 100V and at a case temperature of 25 °C. It needs adequate heatsinking. Since the MOSFET can dissipate a finite amount of maximum power, when you increase the power supply voltage, you must reduce the load current accordingly. The voltage divider part including the R1 and R2 resis...