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SPT7920

Figure 4 - Digital Output Characteristics

3.5 V

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)

0.8 V

0.5 V

Invalid

Data

DATA OUT

(Equivalent)

Invalid

Data

(14 ns typ.)

(N-1)

(N-2)

(N-1)

Invalid

Data

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

operation. This feature makes it possible to include the

SPT7920 into higher resolution systems.

EVALUATION BOARD

The EB7920 evaluation board is available to aid designers in

demonstrating the full performance of the SPT7920. This

board includes a reference circuit, clock driver circuit, output

data latches and an on-board reconstruction of the digital

data. An application note (AN7920) describing the operation

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

SPT7920 is also available. Contact the factory for price and

availability.