Datasheet

7 www.national.com
bypassing the low frequency filter.
Where A0, A1 select the channel under test, ac-
cording to the following table
Test Modes TST PDN0 PDN1 PDN2 PDN3 Description
Normal Operation 0 x x x x
Single Channel Digital Loopback 1 1 1 A0 A1 Ch. select with PDN2, PDN3
Single Channel Analog Loopback 1 0 1 A0 A1 Ch. select with PDN2, PDN3
Single Channel DC Conversion 1 1 0 A0 A1 Ch. select with PDN2, PDN3
4 Channels Digital Loopback 1 0 0 0 0
4 Channels Analog Loopback 1 0 0 0 1
4 Channels DC Conversion 1 0 0 1 0
Invalid States 1 0 0 1 1
A0 A1 Channel Selected
0 0 Channel 0
1 0 Channel 1
0 1 Channel 2
1 1 Channel 3
Functional Description (continued)