CD4518 Dual BCD Up Counter

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CD4518 Dual BCD Up Counter consists of two identical, internally synchronous 4-stage counters. The counter stages are D-type flip-flops having interchangeable CLK and EN lines for incrementing on either the positive going or negative going transition. The IC also offers many features such as high noise immunity and low thermal dissipation. The IC is always available in 16 – pin hermetically sealed package and is directly interfaceable with every TTL, CMOS & NMOS device. . The counter can be cascaded in the ripple mode by connecting Q4 to the enable input of the subsequent counter while the CLOCK input of the latter is held low.

What is A BCD Up Counter?

A binary coded decimal (BCD) Up Counter consists of four synchronously clocked D-type flip-flops connected as a counter. It can either count up from zero to nine. The output of a BCD counter is always indicated in binary format. It goes through 10 unique combinations of output & RESETS for every new clock input. A BCD counter can count 0000, 0001, 0010, 1000, 1001, 1010, 1011, 1110, 1111, 0000, and 0001 and so on.

CD4518 Key Features

High Voltage Types (20V Rating)
CD4518BMS Dual BCD Up Counter
CD4520BMS Dual Binary Up Counter
Medium Speed Operation
- 6MHz Typical Clock Frequency at 10V
Positive or Negative Edge Triggering
Synchronous Internal Carry Propagation
100% Tested for Quiescent Current at 20V
5V, 10V and 15V Parametric Ratings
Maximum Input Current of 1µA at 18V Over Full Package Temperature Range; 100nA at 18V and +25oC
Noise Margin (Over Full Package/Temperature Range)
- 1V at VDD = 5V
- 2V at VDD = 10V
- 2.5V at VDD = 15V

CD4518 Pinout

Pin No	Pin Name	Description
1	CLOCK A	clock pin of counter A
2	ENABLE A	enable pin of counter A
3	Q1A	output pin 1 of counter A
4	Q2A	output pin 2 of counter A
5	Q3A	output pin 3 of counter A
6	Q4A	output pin 4 of counter A
7	RESET A	reset pin of counter A
8	VSS	source supply
9	ENABLE B	enable pin of counter B
10	CLOCK B	clock pin of counter B
11	Q1B	output pin 1 of counter B
12	Q2B	output pin 2 of counter B
13	Q3B	output pin 3 of counter B
14	Q4B	output pin 4 of counter B
15	RESET B	reset pin of counter B
16	VDD	drain supply