IC Up/Down Counter Chips
4-Bit IC Up/Down Counter Circuit
IC Up/Down Counter. Presettable Synchronous 4-Bit Up/Down Counters.
Presetting the counter to the number on the preset data inputs (Input A - Input D) is accomplished by a LOW asynchronous parallel load input (Load). The counter is incremented on the low-to-high transition of the UP input (and a high level on the Clock- DOWN) and decremented on the low to high transition of the DOWN input (and a high level on the UP input). A high level on the CLR input overrides any other input to clear the counter to its zero state. The Terminal Count up (CO) goes low half a clock period before the zero count is reached and returns to a high level at the zero count.
The Terminal Count Down (BO) in the count down mode likewise goes low half a clock period before the maximum count (9 in the 192 and 15 in the 193) and returns to high at the maximum count. Cascading is effected by connecting the CO [carry] and BO [borrow] outputs of a less significant counter to the Clock-Up [UP] and Clock-Down [DOWN] inputs, respectively, of the next most significant counter.
A Counter would be considered standard logic or glue logic when a discrete IC is used. However, because of the internal complexity, an Identity Comparator would also be considered an MSI Function [Medium Scale Integration]. Also refer to a Counter in VHDL.
4-bit Counters by Function:
Note in most cases when a 74xx device is listed, but a 54xx device may also available.
74xx represents the commercial temperature range and 54xx represents the industrial [military] temperature range [IC Prefixes].
74190 Synchronous Up/Down BCD Counter
74191 Synchronous Up/Down 4-Bit Binary Counter
74192 Up / Down Decade Counter
74193 Presettable Synchronous 4-Bit Binary Up/Down Counters
Standard TTL part numbers are shown but it's more likely that a newer logic family would still be in production; 54AC190, 54ACT191, 54HC192 and so on.
Part number Decode [SN54AC192x]
SN; designated Texas Instruments [Company prefix Prefixes]
54; military temperature range [IC temp Ranges]
AC; Advanced CMOS [Logic Families]
192; logic function [4-bit Decade Counter]
x; package style [Types of IC Packages]
MIL-M-38510/344: Advanced Schottky TTL, Decade Counters
54F160, 54F162, 54F190, 54F192
Note the 'F' or Fast series is the same TTL family as the 'AS' or Advanced Schottky series.
Editor note; Many TTL logic ICs have alternate pin outs so keep that in mind when reviewing parts or functional pinouts. In almost all cases any time you see a package pin out, that pinout is for the common part and not the alternate part, but you never know. While writing this, I don't recall if this component has an alternate pin out, but it's something to think about.