AD569

REV. A

–12–

Preceding the second flash, the residue signal must be amplified

by a factor of 256. The OP37 provides a gain of 25.6 and the

AD630 provides another gain of 10. In this case, the AD630

acts as a gain element as well as a channel control switch. The

second flash conversion yields a 9-bit word. This provides one

extra bit of overlap for digital correction of any errors that oc-

curred in the first flash. The correction bit is digitally added to

the first flash before the entire 16-bit output is strobed into the

output register.

Figure 22. 16-Bit Subranging ADC

OUTLINE DIMENSIONS

Dimensions shown in inches and (mm).

28-Pin Ceramic DIP (D)

28-Pin Plastic DIP (N)

28-Pin Plastic Leaded Chip Carrier (P)