器件名称:
M74HC257B1R
功能描述:
QUAD 2 CHANNEL MULTIPLEXER (3-STATE)
文件大小:
190.8KB 共11页
简 介:
M74HC257 QUAD 2 CHANNEL MULTIPLEXER (3-STATE) s s s s s s s HIGH SPEED : tPD = 11 ns (TYP.) at VCC = 6V LOW POWER DISSIPATION: ICC =4A(MAX.) at TA=25°C HIGH NOISE IMMUNITY: VNIH = V NIL = 28 % VCC (MIN.) SYMMETRICAL OUTPUT IMPEDANCE: |IOH| = IOL = 6mA (MIN) BALANCED PROPAGATION DELAYS: tPLH tPHL WIDE OPERATING VOLTAGE RANGE: VCC (OPR) = 2V to 6V PIN AND FUNCTION COMPATIBLE WITH 74 SERIES 257 DIP SOP TSSOP ORDER CODES PACKAGE DIP SOP TSSOP TUBE M74HC257B1R M74HC257M1R T&R M74HC257RM13TR M74HC257TTR DESCRIPTION The M74HC257 is an high speed CMOS QUAD 2 CHANNEL MULTIPLEXER (3-STATE) fabricated with silicon gate C2MOS technology. This IC is composed of an independent 2-channel multiplexer with common SELECT and ENABLE (OE) input. The M74HC257 is a non-inverting multiplexer. When the ENABLE input is held "High", outputs of the IC become in a High-Impedance state. If SELECT input is held low, "A" data is selected, when SELECT is high , "B" data is chosen. All inputs are equipped with protection circuits against static discharge and transient excess voltage. PIN CONNECTION AND IEC LOGIC SYMBOLS August 2001 1/11 M74HC257 INPUT AND OUTPUT EQUIVALENT CIRCUIT PIN DESCRIPTION PIN No 1 2, 5, 14, 11 3, 6, 13, 10 4, 7, 12, 9 15 8 16 SYMBOL SELECT 1A to 4A 1B to 4B 1Y to 4Y OE GND Vcc NAME AND FUNCTION Common Data Select Input Data Input From Source A Data Input From Source B 3 State Multiplexer Outputs 3 State Output Enable Inputs (Active Low) Ground (0V) Positive Supply ……