Alarm Circuit - OKIDATA ML590 Service Manual

Page: 63
Service Guide ML590/ML591
Chapter 2 Principles of Operation

2.1.08 Alarm Circuit

Driver Circuit Alarm Processing
The printhead driver output, the head gap magnet output and the color ribbon magnet drive signal
are monitored at R670 and C15, and the POWER OFF-P signal is output by the comparator
(Location 01A: IC2901) when driven for more than the specified time. This signal becomes the
ALM signal. The ALM signal is sent to the power supply board and causes the DC voltages to be
turned off.
Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business
Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com)