ADT75

I have a problem about ADT75A (SOIC-8).

When power-up, I read from chip 5 registers:

TEMP = 0x0000

CONF = 0x0000

THYST = 0x0000  (???)

TOS = 0x5000

ONESHOT = 0x0000

Loop (period ~170ms) read from TEMP registers: 0x0000 

Second board have MAX75 - no problem absolute, TEMP = 26C.

Case mark on top:

ADT75A

#1134

4106

Case mark on bottom:

#134

2194106

PHIL

Help me... I don't have extra MAX75