9042 Datasheet, PDF (17/26 Pages) Maxwell Technologies – 12-Bit, 41 MSPS A/D Converter

12-Bit, 41 MSPS A/D Converter
9042
The 9042 encode inputs are connected to a differential input stage (See Figure 3). With no input connected to either
the ENCODE or input, the voltage dividers bias the inputs to 1.6 volts. For TTL or CMOS usage, the encode source
should be connected to ENCODE. ENCODE should be decoupled using a low inductance or microwave chip capacitor
to ground. Devices such as AVX 05085C103MA15, a 0.01 mF capacitor, work well.
If a logic threshold other than the nominal 1.6 V is required, the following equations show how to use an external resis-
tor, RX, to raise or lower the trip point (See Figure 3; R1 = 17k, R2 = 8k).
to lower logic threshold.
Figure 20. Lower Logic Threshold for Encode
to raise logic threshold.
01.07.05 REV 7
All data sheets are subject to change without notice 17
©2005 Maxwell Technologies
All rights reserved.