Ultra-Precise, Current-Sense Amplifier

 

 This ultra-precise current sense amplifier that can measure voltage drops across shunt resistor, R1 over a wide common mode range from 2.7 V to 120 V. 50Ohm resistor has been chosen so that 1A current will provide 1V at the output pin.

Driving a Bicolor LED from a Single Output Pin

 

This circuit demonstrates how to control bi-color LED from a single output pin using two PNP transistors. Java Script simulation link is as below.

                                   👉  https://tinyurl.com/22y3w9er                                  

Protecting Microcontroller Input TINA (TI) Simulation

Over Current Protection at Output Stage/ Pins

 

This circuit helps to limit the output current less than 20mA which can be sense and set by R1 & R8. It also disconnects I/O when the output shorts to positive high voltage or negative high voltage by limiting the current.

The diode, D1at the output and 5V0 pin is used to suppress the kick-back voltage from an inductive load that is excited when the drivers are turned off (stop sinking) and the stored energy in the coils causes a reverse current to flow into the coil supply through the kick-back diode

How to use MOSFET for Hide Side Switching

 

This circuit can be used for high voltage (100V max) and high current (33.6A) high side load switching. P-Ch MOSFET,Q1 has been chosen as it as very low ON-Resistance. For high voltage switching, R1 and R2 help to limit the VGS not to exceed VGS max. Another option is adding Zener diode across Gate and Source. N-CH MOSFET, ON/OFF control is driven by small signal N-CH MOSFET, Q2. When ON/OFF CTRL is low Q2 is OFF. When it is high, Q2 activate lowering P-CH gate voltage via R2 which also limits the current.

Overvoltage Protection

 

This circuit monitor VIN and protect the output voltage by a series connected transistor Q14. During over voltage condition Q14 B is turn on which cause Q14A to disconnect output to VIN. Desired overvoltage limit is set by D10 plus VBE of Q14. For example, if the required cutout voltage is 12V, Zener voltage of D10 has to be 12-0.6= 11.4 V.