isppac-powr1220at8 Lattice Semiconductor Corp., isppac-powr1220at8 Datasheet - Page 16

• Manufacturer Part Number: isppac-powr1220at8
• Description: In-system Programmable Power Supply Monitoring, Sequencing And Margining Controller
• Manufacturer: Lattice Semiconductor Corp.

Lattice Semiconductor
Figure 1-8. (a) Power Supply Voltage Ramp-up and Ramp-down Waveform and the Resulting Comparator
Output, (b) Corresponding to Upper and Lower Trip Points
During power supply ramp-up the comparator output changes from logic 0 to 1 when the power supply voltage
crosses the upper trip point (UTP). During ramp down the comparator output changes from logic state 1 to 0 when
the power supply voltage crosses the lower trip point (LTP). To monitor for over voltage fault conditions, the UTP
should be used. To monitor under-voltage fault conditions, the LTP should be used.
Tables 1 and 2 show both the under-voltage and over-voltage trip points, which are automatically selected in soft-
ware depending on whether the user is monitoring for an over-voltage condition or an under-voltage condition.
Comparator Logic Output
UTP
1-16
LTP
ispPAC-POWR1220AT8 Data Sheet
(a)
(b)