the first SCLK edge after CS goes low is a rising edge, all

four leading zeroes will be valid on the first four falling edges

of SCLK. If instead the first SCLK edge after CS goes low is

a falling edge, the first leading zero may not be set up in time

for a microprocessor or DSP to read it correctly. The remain-

ing data bits are still clocked out on the falling edges of

SCLK.

3.0 ADCS7476/77/78 TRANSFER FUNCTION

The output format of the ADCS7476/77/78 is straight binary.

Code transitions occur midway between successive integer

LSB values. The LSB widths for the ADCS7476 is V

4096; for the ADCS7477 the LSB width is V

ADCS7478, the LSB width is V

characteristic for the ADCS7476 and ADCS7477 is shown in

Figure 6, while the ideal transfer characteristic for the

ADCS7478 is shown in Figure 7.

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FIGURE 6. ADCS7476/77 Ideal Transfer Characteristic

20057712

FIGURE 7. ADCS7478 Ideal Transfer Characteristic

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