Rochester Electronics CA3140AT/B

The CA3140A and CA3140 are IC op-amps that combine the advantages of high-voltage PMOS transistors and high-voltage bipolar transistors on a single monolithic chip. The input circuits of these BiMOS op-amps employ gate-protected MOSFET (PMOS) transistors to provide very high input impedance, very low input current, and high-speed performance. They operate from supply voltages ranging from 4V to 36V (single or dual supply). These op-amps are internally phase-compensated for stable operation in unity-gain follower configurations, and an access terminal is provided for an external capacitor when additional frequency rolloff is required. Terminals for input offset voltage nulling are also provided. The use of PMOS FETs in the input stage allows the common-mode input voltage range to extend to 0.5V below the negative supply terminal, which is an important feature for single-supply applications. The output stage uses bipolar transistors with built-in protection against damage from short-circuits at the output terminal to either supply rail or ground. The CA3140A and CA3140 are suitable for operation at supply voltages up to 36V (±18V).

• MOSFET input stage
• Very high input impedance (ZIN) — typical 1.5TΩ
• Very low input current (IJ) — typical 10pA at ±15V
• Wide common-mode input voltage range (VICR) — swings 0.5V below negative supply rail
• Output swing complementary to input common-mode range
• Direct drop-in replacement for industry-standard type 741 in most applications

• Ground-referenced single-supply amplifiers in automotive and portable instruments
• Sample-and-hold amplifiers
• Long-duration timers/multivibrators
• Photocurrent instrumentation
• Peak detectors