SN74LS170.pdf , 데이터시트 , 데이타시트

No Preview Available !

4 x 4 REGISTER FILE

OPEN-COLLECTOR

The TTL / MSI SN54 / 74LS170 is a high-speed, low-power 4 x 4 Register

File organized as four words by four bits. Separate read and write inputs, both

address and enable, allow simultaneous read and write operation.

Open-collector outputs make it possible to connect up to 128 outputs in a

wired-AND configuration to increase the word capacity up to 512 words. Any

number of these devices can be operated in parallel to generate an n-bit

length.

The SN54 / 74LS670 provides a similar function to this device but it features

3-state outputs.

• Simultaneous Read/ Write Operation

• Expandable to 512 Words of n-Bits

• Typical Access Time of 20 ns

• Low Leakage Open-Collector Outputs for Expansion

• Typical Power Dissipation of 125 mW

CONNECTION DIAGRAM DIP (TOP VIEW)

VCC D1 WA WB EW ER Q1 Q2

16 15 14 13 12 11 10 9

1 2 3 4 56 78

D2 D3 D4 RB RA Q4 Q3 GND

NOTE:

The Flatpak version

has the same pinouts

(Connection Diagram) as

the Dual In-Line Package.

PIN NAMES

LOADING (Note a)

HIGH

LOW

D1 – D4

WA, WB

RA, RB

Q1 – Q4

Data Inputs

Write Address Inputs

Write Enable (Active LOW) Input

Read Address Inputs

Read Enable (Active LOW) Input

Outputs (Note b)

0.5 U.L.

1.0 U.L.

0.5 U.L.

1.0 U.L.

Open-Collector

0.25 U.L.

0.5 U.L.

0.25 U.L.

0.5 U.L.

5 (2.5) U.L.

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. The Output HIGH drive must be supplied by an external resistor to VCC.

SN54/74LS170

4 x 4 REGISTER FILE

OPEN-COLLECTOR

LOW POWER SCHOTTKY

J SUFFIX

CERAMIC

CASE 620-09

N SUFFIX

PLASTIC

CASE 648-08

D SUFFIX

SOIC

CASE 751B-03

ORDERING INFORMATION

SN54LSXXXJ

SN74LSXXXN

SN74LSXXXD

Ceramic

Plastic

SOIC

LOGIC SYMBOL

12 15 1 2 3

WA EW

D1 D2 D3 D4

5 RA

4 RB ER Q1 Q2 Q3 Q4

11 10 9 7 6

VCC = PIN 16

GND = PIN 8

FAST AND LS TTL DATA

5-1

No Preview Available !

WA 14

SN54 / 74LS170

LOGIC DIAGRAM

D4 D3

D2 D1

1 15

WORD

G D1

WORD

G D2

VCC = PIN 16

GND = PIN 8

= PIN NUMBERS

WORD

G D3

FAST AND LS TTL DATA

5-2

No Preview Available !

SN54 / 74LS170

WRITE FUNCTION TABLE (SEE NOTES A, B, AND C)

WRITE INPUTS

WORD

WB WA EW

L L L Q = D Q0 Q0 Q0

Q0 Q = D Q0

H L L Q0 Q0 Q = D Q0

H H L Q0 Q0 Q0 Q = D

X X H Q0 Q0 Q0 Q0

READ FUNCTION TABLE (SEE NOTES A AND D)

READ INPUTS

OUTPUTS

RB RA ER

L L L W0B1 W0B2 W0B3 W0B4

L H L W1B1 W1B2 W1B3 W1B4

H L L W2B1 W2B2 W2B3 W2B4

H H L W3B1 W3B2 W3B3 W3B4

XXH

NOTES: A. H = HIGH Level. L = LOW Level, X = Irrelevant.

NOTES: B. (Q = D) = The four selected internal flip-flop outputs will assume the states applied to the four external data inputs.

NOTES: C. Q0 = the level of Q before the indicated input conditions were established.

NOTES: D. W0B1 = The first bit of word 0, etc.

GUARANTEED OPERATING RANGES

Symbol

Parameter

VCC

Supply Voltage

TA Operating Ambient Temperature Range

VOH

IOL

Output Voltage — High

Output Current — Low

Min Typ Max Unit

54 4.5 5.0 5.5

74 4.75 5.0 5.25

54 – 55 25 125 °C

74 0 25 70

54, 74

5.5 V

54 4.0 mA

74 8.0

DC CHARACTERISTICS OVER OPERATING TEMPERATURE RANGE (unless otherwise specified)

Limits

Symbol

Parameter

Min Typ Max Unit

Test Conditions

VIH Input HIGH Voltage

2.0

Guaranteed Input HIGH Voltage for

All Inputs

VIL Input LOW Voltage 74

0.7 Guaranteed Input LOW Voltage for

0.8 V All Inputs

VIK

IOH

VOL

Input Clamp Diode Voltage

Output HIGH Current

54, 74

Output LOW Voltage

54, 74

– 0.65 – 1.5 V VCC = MIN, IIN = – 18 mA

100 µA VCC = MIN, VOH = MAX

0.25 0.4

0.35 0.5

V IOL = 4.0 mA VCC = VCC MIN,

VIN = VIL or VIH

V IOL = 8.0 mA per Truth Table

Input HIGH Current

Any D, R, W

IIH ER, EW

Any D, R, W

ER, EW

Input LOW Current

IIL Any D, R, W

ER, EW

ICC Power Supply Current

20 µA VCC = MAX, VIN = 2.4 V

0.1

0.2

mA VCC = MAX, VIN = 7.0 V

– 0.4 mA VCC = MAX, VIN = 0.4 V

– 0.8

40 mA VCC = MAX

FAST AND LS TTL DATA

5-3

No Preview Available !

SN54 / 74LS170

AC CHARACTERISTICS (TA = 25°C)

Symbol

tPLH

tPHL

tPLH

tPHL

tPLH

tPHL

tPLH

tPHL

Parameter

Propagation Delay, Negative-

Going ER to Q Outputs

Propagation Delay, RA or RB

to Q Outputs

Propagation Delay, Negative-

Going EW to Q Outputs

Propagation Delay, Data Inputs

to Q Outputs

AC SETUP REQUIREMENTS (TA = 25°C)

Symbol

tLATCH

Parameter

Pulse Width, ER, EW

Setup Time, Data to EW

Setup Time, WA, WB to EW

Hold Time, Data to EW

Hold Time, WA, WB to EW

Latch Time

Limits

Min Typ Max

20 30

25 40

24 40

30 45

26 40

30 45

22 35

Unit

Test Conditions

Figure 1

Figure 2

Figure 1

VCC = 5.0 V

CL = 15 pF

RL = 2.0 kΩ

Figure 1

Limits

Min Typ Max

5.0

Unit

Test Conditions

VCC = 5.0 V

RL = 2.0 kΩ

VOLTAGE WAVEFORMS

WRITE-SELECT

INPUT WA or WB

DATA INPUT

D1, D2, D3 or D4

WRITE-ENABLE

INPUT EW

READ-SELECT

INPUT RA or RB

READ-ENABLE

INPUT ER

OUTPUT

Q1, Q2, Q3 or Q4

Vref

tsu(W)

Vref

th(W)

Vref

tsu(D)th(D)

Vref

tlatch

Vref

Vref Vref

tPHL tPLH

Vref Vref

tPHL tPLH

VOH

VOL

Figure 1

DATA INPUT

D1, D2, D3 or D4

WRITE-ENABLE

INPUT EW

OUTPUT

Q1, Q2, Q3 or Q4

Vref

tPLH

Vref

DATA INPUT

D1, D2, D3 or D4

WRITE-ENABLE

INPUT EW

OUTPUT

Q1, Q2, Q3 or Q4

Vref

tPHL

Vref

Figure 2

Vref

tPHL

Vref

tPLH

Vref

VOH

VOL

FAST AND LS TTL DATA

5-4