2 Watt stereo amplifier with LM1877N-9

Photodiode-amplifier

This circuit uses a CA5422 dual BiMOS microprocessor op amp. The bootstrap amplifiers minimize bias currents while maintaining electrostatic discharge protection.

High-current-oscillator

The oscillator output of the XR-567 can be amplified using the output amplifier and high-current logic output available at pin 8. In this manner, the circuit can switch 100-mA load currents without sacrificing oscillator stability.

Sample and hold

The 2N4393 JFET was selected because of its low less (< 100 pA), very low ID (< 100 pA) and low pinchoff voltage

Bell circuit with two 555 timers

This simple Bell circuit uses two 555 timers. The frequency is controlled by the capacitors that must be preserved almost identical in value to each other for best results. Fine tuning is done with R1 and R2.

Variable-Voltage Reference Source

The noninvertiiig terminal of the op amp is grounded, and the circuit uses the voltage at the inverting t

Fast Video Signal Amplitude Measurer Circuit

Video-signal amplitude can be measured with this simple circuit, which is basically a modified standard peak detector. The device can verify RGB generated by video RAMDACs. Ul is a high-speed buffer and U2 is a latched comparator. CI is a hold capacitor. Reset is performed by Q3. U2 has a latch...

10Mhz-frequency-counter

The circuit consists of ICM7208 seven-decade counter U1, ICM7207A oscillator controller U2, and CA3130 biFET op amp U3. IC U1 counts input signals, decodes them to 7-segment format, and outputs signals that are used to drive a 7-digit display. IC U2 provides the timing for U1, while U3...

Semiconductor-fail-alarm

False alarms produced by semiconductor failure are impossible with this burglar-alarm circuit equipped with relays. What"s more, the circuit is virtually immune to false triggering. With a standby current of less than 0.1 mA, the circuit offers all the features an alarm needs: entry and exit...