Evaluation Board User Guide for ISL282X7SOICEVAL2Z
The ISL282X7SOICEVAL2Z evaluation board is a set design platform that contains all the circuits required to characterize the key performance parameters of the ISL282X7 SOIC-8 packaged operational amplifier, using various user-defined test circuits. The ISL282X7 op amps feature low bias current, low noise, low offset and temperature drift.
Key Features of the Evaluation Board
The ISL282X7SOICEVAL2Z is designed to enable the IC to operate from a single supply +4.5 VDC to 40 VDC or from a split supply, ±2.25VDC to ±20V. The board is configured as a dual op amp with a differential connection input closed-loop gain of 10. An external voltage reference (VREF) pin and a user-selectable voltage divider-filter are included.
Power Supply (Picture 1)
External power connections via +V-V, VREF, and ground connections on the evaluation board. For single-supply operation, the -V and ground pins are tied together, the negative side of the power supply. For split power supplies, the +V and -V terminals are connected to their respective power supply terminals. Decoupling capacitors C2 and C4 are connected to their respective power supplies via
Zero ohm resistors for R16 and R31. These resistors are 0Ω, but can be changed by the user to provide additional power supply filtering, or to reduce the voltage rise rate to less than ±1V/µs. Two extra capacitors, C3 and C5
Tightly connected sections filter out high frequency noise. The circuit in reverse reverse diode D1 protects in the event of accidental polarity reversal.
Amplifier Configuration (Figure 2)
A schematic with components, 1/2 of the op amp is provided as shown in Figure 2. This circuit implements a differential input amplifier with a closed-loop gain of 10. “The circuit can operate on a single supply or dual supplies. The VREF pin must be tied to ground to establish dual supply ground referenced input operation, or any reference level can be set externally for single supply operation. VREF should not be floating.