
STMicroelectronics
DESCRIPTION
The HCC/HCF40147B CMOS encoder features priority encoding of the inputs to ensure that only the highest order data line is encoded. Ten data input lines (0-9) are encoded to four line (8, 4, 2, 1) BCD. The highest priority line is line 9. All four output lines are logic 1 (VSS) when all input lines are logic 0. All inputs and outputs are buffered, and each output can drive one TTL Low Power Schottky load. The HCC/HCFF40147 is functionally similar to the T54/T74LS147 if pin 15 is tied low.
■ ENCODES 10 LINE TO 4 LINE BCD
■ ACTIVE LOW INPUTS AND OUTPUTS
■ STANDARDIZED, SYMMETRICAL OUTPUT CHARACTERIZATION
■ 100 % TESTED FOR QUIESCENT CURRENT AT 20 V
■ 5V, 10V AND 15V PARAMETRIC RATINGS
■ MAXIMUM INPUT CURREENT OF 1 µA AT 18V OVER FULL PACKAGE TEMPERATURE RANGE; 100 nA AT 18 V AND 25 oC
■ NOISE MARGIN (FULL PACKAGE TEMPERATURE RANGE): 1V AT VDD = 5V, 2V AT VDD = 10V, 2.5V AT VDD = 15V
APPLICATIONS:
■ KEYBOARD ENCODING
■ 10 LINE TO BCD ENCODING
■ RANGE SELECTION