ELECTRICAL CHARACtERISTICS:

PARAMETER

SYMBOL

MIN

MAX

UNITS

Count Test and Count frequency

(Vss = +5V ± 5%)

DC

7.5

MHz

(Vss = +10V)

DC

6

MHz

(Vss = +15V)

DC

5

MHz

Scan frequency

DC

500

kHz

Count Pulse Width

(Pulse applied to B4/D2 or B8/D2;

‘OR’ combination ofB4/D2 and B8/D2)

(Vss = +5V ± 5%)

62

-

ns

(Vss = +10V)

83

-

ns

(Vss = +15V)

100

-

ns

**Propagation Delay

(B4/D2(H-L) to B8/D2 (L-H) at

Vss -1.0V)

Count Ripple Time

Overlap

10

ns

Load Pulse Width

4

-

µs

Load Removal Time

-

1

µs

Reset Pulse Width

4

-

µs

Reset Removal Time

-

1

µs

Rise and Fall Time

Count Pulse

-

4

µs

Reset Pulse

-

4

µs

Test Count Pulse

-

80

µs

*Strobe Guard Band time

400

-

ns

(fSC

≤ 100kHz ≤ 250kHz)

*Strobe Guard Band time

200

-

ns

(100kHz

≤ fSC ≤ 250kHz)

*Strobe Guard Band time

200

-

ns

(250kHz

≤ fSC≤ 500kHz)

negative edge only

*Defines the minimum time from strobe edges to switching BCD data.

BCD CNTR 1

1

2

4

8

PRESCALE

DIGIT 1

B1/D1 - B8/D1

BCD CNTR 2

1

2

4

8

PRESCALE

DIGIT 2

B1/D1 - B8/D1

LS7031

DIGIT STROBES

1

2

4

8

BLANK

BCD TO SEVEN

SEGMENT

DECODER/DRIVER

(LSD)

(MSD)

750MHz

75MHz

FIGURE 3. TYPICAL APPLICATION

DIGIT DRIVERS

8 DIGIT DISPLAY

7.5MHz

b c d e f g

a

7031-110201-3

FIGURE 2. GUARD BANDED STROBE

BCD

STROBE

**Propagation Delay and Pulse Width

Vss - 1.0

Vss - 1.0

B4/D2

B8/D2

B4/D2

or

B8/D2

The information included herein is believed to be

accurate and reliable. However, LSI Computer Systems,

Inc. assumes no responsibilities for inaccuracies, nor for

any infringements of patent rights of others which may

result from its use.