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SPT7820

Figure 4 - Digital Output Characteristics

3.5 V

N+1

Rise Time

6 nsec

6 ns

typ.

CLK In

N

2.4 V

Invalid

Data

(N-1)

(N-2)

(N-1)

Data Out

(Equivalent)

Invalid

Data

Data Out

(Actual)

(N-2)

(N-1)

(N)

2.4 V

0.8 V

0.5 V

tpd1

(14 ns typ.)

Invalid

Data

Invalid

Data

OVERRANGE OUTPUT

The OVERRANGE OUTPUT (D10) is an indication that the

analog input signal has exceeded the positive full scale input

voltage by 1 LSB. When this condition occurs, D10 will switch

to logic 1. All other data outputs (D0 to D9) will remain at

logic 1 as long as D10 remains at logic 1. This feature makes

it possible to include the SPT7820 into higher resolution

systems.

EVALUATION BOARD

The EB7820 evaluation board is available to aid designers in

demonstrating the full performance of the SPT7820. This

board includes a reference circuit, clock driver circuit, output

data latches and an on-board reconstruction of the digital

data. An application note describing the operation of this

board as well as information on the testing of the SPT7820 is

also available. Contact the factory for price and availability.