ICS1531 datasheet(60/76 Pages) ICST

60 / 76 page

ICS1531 Rev N 12/1/99

December, 1999

Chapter 8

Layout and Power Considerations

ICS1531 Data Sheet - Preliminary

8.2

Power Considerations

8.2.1

Power-On Reset

The ICS1531 incorporates special internal power-on reset circuitry that requires no external reset signal

connections.

• During normal operations, the VDD supply voltage for the ICS1531 must remain within the

recommended operating conditions. (See Section 9.2, “Recommended Operating Conditions”.)

• To reset the ICS1531, do the following:

– Reduce the level of the VDD supply voltage to the ICS1531 (and the voltage seen on all ICS1531

pins) so that it is below Vth, the threshold voltage for time t1. (For a typical threshold voltage Vth, see

Section 10.2, “Power-On Reset Timing”.)

– Keep the supply voltage below that threshold voltage for time t1, such that power-conditioning

capacitors for the printed circuit board are drained and the proper reset state is latched. (For a typical

time t1, see Section 10.2, “Power-On Reset Timing”.)

• A successful power-on reset results in all the ICS1531 registers having the appropriate reset values as

stated in the tables in Chapter 6, “Register Set”.

8.2.2

Power Conservation

For information on how to conserve power, see the ICS1531 application notes.

8.2.3

Layout for Power Supply Voltages

See Section 8.1.1, “General Guidelines for Printed Circuit Board Layout”.

ICS1531 Datasheet(PDF) 60 Page - Integrated Circuit Systems