Document
SN54/74LS195A UNIVERSAL 4-BIT SHIFT REGISTER
The SN54 / 74LS195A is a high speed 4-Bit Shift Register offering typical shift frequencies of 39 MHz. It is useful for a wide variety of register and counting applications. It utilizes the Schottky diode clamped process to achieve high speeds and is fully compatible with all Motorola TTL products.
UNIVERSAL 4-BIT SHIFT REGISTER
LOW POWER SCHOTTKY
• • • • •
Typical Shift Right Frequency of 39 MHz Asynchronous Master Reset J, K Inputs to First Stage Fully Synchronous Serial or Parallel Data Transfers Input Clamp Diodes Limit High Speed Termination Effects
CONNECTION DIAGRAM DIP (TOP VIEW)
VCC 16 Q0 15 Q1 14 Q2 13 Q3 12 Q3 11 CP 10 PE 9
NOTE: The Flatpak version has the same pinouts (Connection Diagram) as the Dual In-Line Package.
J SUFFIX CERAMIC CASE 620-09
16 1
16 1
N SUFFIX PLASTIC CASE 648-08
1 MR
2 J
3 K
4 P0
5 P1
6 P2
7 P3
8 GND
16
PIN NAMES
LOADING (Note a) HIGH LOW 0.25 U.L. 0.25 U.L. 0.25 U.L. 0.25 U.L. 0.25 U.L. 0.25 U.L. 5 (2.5) U.L. 5 (2.5) U.L.
1
D SUFFIX SOIC CASE 751B-03
PE P0 – P3 J K CP MR Q0 – Q3 Q3
Parallel Enable (Active LOW) Input Parallel Data Inputs First Stage J (Active HIGH) Input First Stage K (Active LOW) Input Clock (Active HIGH Going Edge) Input Master Reset (Active LOW) Input Parallel Outputs (Note b) Complementary Last Stage Output (Note b)
0.5 U.L. 0.5 U.L. 0.5 U.L. 0.5 U.L. 0.5 U.L. 0.5 U.L. 10 U.L. 10 U.L.
ORDERING INFORMATION
SN54LSXXXJ SN74LSXXXN SN74LSXXXD Ceramic Plastic SOIC
LOGIC SYMBOL
9 4 5 6 7
NOTES: a. 1 TTL Unit Load (U.L.) = 40 µA HIGH/1.6 mA LOW. b. The Output LOW drive factor is 2.5 U.L. for Military (54) and 5 U.L. for Commercial (74) b. Temperature Ranges.
2 10 3
J CP K
PE P0 P1 P2 P3 Q3 11
MR Q0 Q1 Q2 Q3 1 15 14 13 12 VCC = PIN 16 GND = PIN 8
FAST AND LS TTL DATA 5-366
SN54/74LS195A
LOGIC DIAGRAM
PE
9 2
J
3
K
4
P0
5
P1
6
P2
7
P3
1
MR
10
CP
R CD Q0 CP S VCC = PIN 16 GND = PIN 8 = PIN NUMBERS Q0
15
R CD CP S Q0
14
R CD CP S Q2
13
R CD Q3 CP S Q3
12 11
Q0
Q1
Q2
Q3 Q3
FUNCTIONAL DESCRIPTION The Logic Diagram and Truth Table indicate the functional characteristics of the LS195A 4-Bit Shift Register. The device is useful in a wide variety of shifting, counting and storage applications. It performs serial, parallel, serial to parallel, or parallel to serial data transfers at very high speeds. The LS195A has two primary modes of operation, shift right (Q0 Q1) and parallel load which are controlled by the state of the Parallel Enable (PE) input. When the PE input is HIGH, serial data enters the first flip-flop Q0 via the J and K inputs and is shifted one bit in the direction Q0 Q1 Q2 Q3 following each LOW to HIGH clock transition. The JK inputs provide the flexibility of the JK type input for special applications, and the simple D type input for general applications by tying the two pins together. When the PE input is LOW, the LS195A appears as four common clocked D flip-flops. The data on the parallel inputs P0, .