ICs & Dips

The 4N28 family is an Industry Standard Single Channel Phototransistor Coupler. This family includes the 4N25, 4N26, 4N27, 4N28. Each optocoupler consists of gallium arsenide infrared LED and a silicon NPN phototransistor. These couplers are Underwriters Laboratories (UL) listed to comply with a 5300 VRMS isolation test voltage. This isolation performance is accomplished through special Vishay manufacturing process. Compliance to DIN EN 60747-5-2 (VDE 0884)/ DIN EN 60747-5-5 pending partial discharge isolation specification is available by ordering option 1. These isolation processes and the Vishay ISO9001 quality program results in the highest isolation performance available for a commercial plastic phototransistor optocoupler. The devices are also available in lead formed configuration suitable for surface mounting and are available either on tape and reel, or in standard tube shipping containers

The 62256 is a high performance CMOS static RAM organized as 32K words by 8 bits. Easy memory expansion is provided by an active LOW chip enable (CE) and active LOW output enable (OE) and tristate drivers. This device has an automatic power-down feature, reducing the power consumption by 99.9 percent when deselected. An active LOW write enable signal (WE) controls the writing/reading operation of the memory. When CE and WE inputs are both LOW, data on the eight data input/output pins (I/O0 through I/O7) is written into the memory location addressed by the address present on the address pins (A0 through A14). Reading the device is accomplished by selecting the device and enabling the outputs, CE and OE active LOW, while WE remains inactive or HIGH. Under these conditions, the contents of the location addressed by the information on address pins are present on the eight data input/output pins. The input/output pins remain in a high impedance state unless the chip is selected, outputs are enabled, and write enable (WE) is HIGH.