PS12 Datasheet, PDF (1/10 Pages) Supertex, Inc – Quad Power Sequencing Controller

PS12
Quad Power Sequencing Controller
Features
► Power supply sequencer with four outputs
► Power-up and power-down sequencing
► Six programmable delays
► Maximum 90V supply voltage
► Input voltage window comparator
► Low power supply current (500µA typical)
► 16-Lead SOIC Package
Applications
► Reduction of transient current demand and
protection of sensitive loads
► Telecom and networking systems
► High voltage MEMS and display driver supplies
Typical Application Circuit
+12V
General Description
Many systems require that their power supplies are enabled
and disabled sequentially in order to reduce transient current
demand on the power bus, or to avoid damage to components
having multiple supply voltages such as microprocessors,
ASICs, MEMS drivers, etc.
The PS12 incorporates a power-up delay timer, a window
voltage comparator, 4 open drain enable outputs, and 6
enable delay timers. The enable delays are individually
programmable for both the power-up (ABCD) and the power-
down (DCBA) sequence.
Power-up and power-down are controlled by a window
comparator formed by the ON and OV voltage comparators.
V_IN voltage within the window initiates power-up; V_IN voltage
outside of the window maintains or initiates power-down. The
power-up sequence may be interrupted while in progress. The
power-down sequence, once initiated, cannot be interrupted
until it is brought to completion.
R₁
3
ON
R₂
4
OV
R₃
2
C_PUD
PUD
TAB
5
15
VIN
1
VEE
PS12NG
TBC
6
TCD
7
TDC
8
TCB
9
11
PSA
12
PSB
13
PSC
14
PSD
TBA
10
R_AB
R_BC
R_CD
R_DC
R_CB
R_BA
ENA
+12V
CONVERTER
ENA
+5V
CONVERTER
ENA
+3.3V
CONVERTER
ENA
+1.8V
CONVERTER
OUT
OUT
OUT
OUT