器件名称:
M74HC257F1R
功能描述:
HC258QUAD 2CHANNEL MULTIPLEXER 3-STATE, INVERTING HC257 QUAD 2 CHANNEL MULTIPLEXER 3-STATE
文件大小:
259.1KB 共12页
简 介:
M54/M74HC257 M54/M74HC258 HC257 QUAD 2 CHANNEL MULTIPLEXER (3-STATE) HC258 QUAD 2 CHANNEL MULTIPLEXER (3-STATE, INVERTING) . . . . . . . . HIGH SPEED tPD = 10 ns (TYP.) at VCC = 5 V LOW POWER DISSIPATION ICC = 4 A (MAX.) at TA = 25 °C HIGH NOISE IMMUNITY VNIH = VNIL = 28 % VCC (MIN.) OUTPUT DRIVE CAPABILITY 15 LSTTL LOADS SYMMETRICAL OUTPUT IMPEDANCE IOH = IOL = 6 mA (MIN.) BALANCED PROPAGATION DELAYS tPLH = tPHL WIDE OPERATING VOLTAGE RANGE VCC (OPR) = 2 V to 6 V PIN AND FUNCTION COMPATIBLE WITH 54/74LS257/258 B1R (Plastic Package) F1R (Ceramic Package) M1R (Micro Package) C1R (Chip Carrier) ORDER CODES : M54HCXXXF1R M74HCXXXM1R M74HCXXXB1R M74HCXXXC1R PIN CONNECTIONS (top view) HC257 DESCRIPTION The M54/74HC257 and the M54/74HC258 are high speed CMOS MULTIPLEXERs fabricated with sili2 con gate C MOS technology. They have the same high speed performance of LSTTL combined with true CMOS low power consumption. These IC’s are composed of an independent 2channel multiplexer with common SELECT and ENABLE INPUT. The M54/74HC258 is an inverting multiplexer while the M54/74HC257 is a non-inverting multiplexer. When the ENABLE INPUT is held ”High”, outputs of both IC’s become high-impedance state. If SELECT INPUT is held ”Low”, ”A” data is selected, when SELECT INPUT is high ”H”, ”B” data is chosen. All inputs are equipped with protection circuits against static discharge and transient excess voltage. October 1992 HC258 1/12 M54/M74HC257/258 INPUT AND OUTPUT EQUIVALENT C……
