器件名称: IZ74HC221AZ
功能描述: DUAL MONOSTABLE MULTIVIBRATOR
文件大小: 283.2KB 共7页
简 介:IN74HC221A
DUAL MONOSTABLE MULTIVIBRATOR
The IN74HC221A is identical in pinout to the LS/ALS221. The device inputs are compatible with standard CMOS outputs; with pullup resistors, they are compatible with LS/ALSTTL outputs. There are two trigger inputs, A INPUT (negative edge) and B INPUT (positive edge). These inputs are valid for rising/falling signals The device may also be triggered by using the RESET input (positive-edge) because of the Schmitt-trigger input; after triggering the output maintains the MONOSTABLE state for the time period determined by the external resistor REXT and capacitor CEXT. Taking RESET low breaks this MONOSTABLE STATE. If the next trigger pulse occurs during the MONOSTABLE period it makes the MONOSTABLE period longer. Outputs Directly Interface to CMOS, NMOS, and TTL Operating Voltage Range: 3.0 to 6.0 V Low Input Current: 1.0 A High Noise Immunity Characteristic of CMOS Devices LOGIC DIAGRAM
1A
DEXT CEXT REXT CEXT DEXT REXT
N SUFFIX PLASTIC 16 1 16 1 D SUFFIX SOIC
ORDERING INFORMATION IN74HC221AN Plastic IN74HC221AD SOIC IZ74HC221AZ Chip TA = -55° to 125° C for all packages
PIN ASSIGNMENT
1 2 3 4 5 6 7 8 16 15 14 13 12 11 10 9 V CC 1REXT/CEXT 1CEXT 1Q 2Q 2RESET 2B 2A
1B 1RESET 1Q 2Q
PIN 16 =VCC PIN 8 = GND
2CEXT 2REXT/CEXT GND
FUNCTION TABLE
A Inputs B RESET H H Outputs Q Q Note Output Enable Inhibit Inhibit Output Enable Output Enable Inhibit
Note X L H L* H* (1) CEXT, REXT, DEXT are external components. * H X H L H* (2) DEXT is a……
