This document introduces Circuit Note CN-0241 Circuits from the Lab™ reference circuits, which are engineered and tested for quick and easy system integration to help solve today’s analog, mixed-signal, and RF design challenges. The document describes the devices connected/referenced, including ADA4096-2 30 V, Micropower, Overvoltage Protection, Rail-to-Rail Input/Output Amplifier, AD7920 250 kSPS, 12-bit, 250 kSPS ADC in 6-Lead SC70, and ADP3336 High Accuracy Ultralow IQ 500 mA anyCAP® Adjustable Low Dropout Linear Regulator.
The document presents Circuit Note CN-0241, a reference circuit designed for high-side current monitoring with input overvoltage protection. It utilizes the ADA4096-2 operational amplifier, which features input protection for voltages up to 32 V higher or lower than the supply rails, preventing latch-up or phase reversal. The circuit is powered by an ADP3336 adjustable low dropout linear regulator and interfaces with an AD7920 ADC for data acquisition.
| Input Overvoltage Protection Range | 32 V higher and lower than supply rails |
|---|---|
| ADA4096-2 Input Bias Current | 120 µA |
| AD7920 Throughput Rate | 250 kSPS |
| AD7920 Power Down Current | 5 µW |
| ADP3336 Shutdown Current | 1 µA |
The ADA4096-2 provides input overvoltage protection for voltages up to 32 V higher or lower than the supply rails without phase reversal or latch-up.
The circuit can be powered down by removing power to the ADP3336 regulator, allowing the power source (e.g., solar panel) to continue operating.
The peak-to-peak noise is approximately 2 LSBs, corresponding to about 0.3 LSB rms.