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SPT7921

Figure 4 - Digital Output Characteristics

EVALUATION BOARD

The EB7921 evaluation board is available to aid designers in

demonstrating the full performance of the SPT7921. This

board includes a reference circuit, clock driver circuit, output

data latches and an on-board reconstruction of the digital

data. An application note (AN7921) describing the operation

of this board as well as information on the testing of the

SPT7921 is also available. Contact the factory for price and

availability.

OVERRANGE OUTPUT

The overrange output (D12) is an indication that the analog

input signal has exceeded the full scale input voltage by

1 LSB. When this condition occurs, the outputs will switch to

logic 1s. All other data outputs are unaffected by this opera-

tion. This feature makes it possible to include the SPT7921

into higher resolution systems.

N+1

Rise Time

6 ns

2.4 V

N

CLK IN

2.4 V

Invalid

Data

6 ns

typ.

(N-2)

(N-1)

(N)

DATA OUT

(Actual)

3.5 V

0.8 V

0.5 V

Invalid

Data

DATA OUT

(Equivalent)

Invalid

Data

(N-1)

(N-2)

(N-1)

Invalid

Data

(14 ns typ.)