Ac electrical characteristics (continued) – Rainbow Electronics DS1124 User Manual

Page 3

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DS1124

5.0V 8-Bit Programmable

Timing Element

_______________________________________________________________________________________

3

Note 1: All voltages are referenced to ground.
Note 2: Measured from rising edge of the input to the rising edge of the output. The programmed delay, t

D

, can be programmed

with values from 0 to 255. See Figure 1.

Note 3: See the

Integral Nonlinearity section and Figure 6.

Note 4: This is the minimum allowable interval between transitions on the input to ensure accurate device operation. This parameter

can be violated but timing accuracy may be impaired and ultimately very narrow pulse widths will result in no output from
the device. See Figure 1.

Note 5: When a 50% duty cycle input clock is used, this defines the highest usable clock frequency. When asymmetrical clock

inputs are used, the maximum usable clock frequency must be reduced to conform to the minimum input pulse-width
requirement. See Figure 1.

Note 6: Faster rise and fall times give the greatest accuracy in measured delay. Slow edges (outside the specification maximum)

can result in erratic operations.

AC ELECTRICAL CHARACTERISTICS (continued)

(V

CC

= +4.75V to +5.25V, T

A

= -40°C to +85°C, unless otherwise noted.)

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

E to Delay Valid

t

EDV

50

μs

E to Delay Invalid

t

EDX

0

ns

Power-Up Time

t

PU

100 ms

Delay Step Size

t

STEP

T

A

= +25°C

-0.75

+0.25

+1

ns

Step 0 Delay

T

D0

(Note

2)

17 20 23 ns

Step 0 Delay Initial Accuracy

V

CC

= 5V, T

A

= +25°C

-0.6

+0.6

ns

Step 0 Voltage Variation

-0.4

+0.4

ns

Step 0 Temperature Variation

0°C to +70°C

-1

+1

ns

Step 0 Temperature Variation

-40°C to +85°C

-1

+1

ns

Step 255 Delay

T

D255

(Note

2)

77 83.75 88 ns

Step 255 Delay Initial Accuracy

V

CC

= 5V, T

A

= +25°C

-0.6

+0.6

ns

Step 255 Voltage Variation

-0.4

+0.4

ns

Step 255 Temperature Variation

0°C to +70°C

-3

+3

ns

Step 255 Temperature Variation

-40°C to +85°C

-5

+5

ns

Integral Nonlinearity
(Deviation from Straight Line)

t

ERR

T

A

= +25°C (Note 3)

-2

0

+2

ns

Minimum Input Pulse Width

t

WI

(Note

4)

40

ns

Minimum Input Period

t

PER

(Note

5)

80

ns

Input Rise and Fall Times

t

R

, t

F

(Note

6)

0 1

μs

t

D0

t

D0

t

D

t

WI

IN

OUT

t

WI

t

D

IN

TIMING REFERENCED TO 1.5V.

OUT

DS1124

Figure 1. Delay Timing Diagram

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