LTC2900 Datasheet, PDF (1/16 Pages) Linear Technology – Programmable Quad Supply Monitor with Adjustable Reset Timer

LTC2900
Programmable Quad Supply
Monitor with Adjustable Reset Timer
FEATURES
s _{Simultaneously Monitors Four Supplies}
s _{16 User Selectable Combinations of 5V, 3.3V, 3V,}
2.5V, 1.8V, 1.5V and/or ±Adjustable Voltage
Thresholds
s _{Guaranteed Threshold Accuracy: ±1.5% of}
Monitored Voltage Over Temperature
s _{Low Supply Current: 43µA Typ}
s _{Adjustable Reset Time}
s _{Small MSOP and 3mm × 3mm DFN Packages}
s _{Manual Reset Pin}
s _{Open-Drain RST Output (LTC2900-1)}
s _{Push-Pull RST Output (LTC2900-2)}
s _{Power Supply Glitch Immunity}
s _{Guaranteed RST for VCC ≥ 1V}
U
APPLICATIO S
s _{Desktop and Notebook Computers}
s _{Multivoltage Systems}
s _{Telecom Equipment}
s _{Portable Battery-Powered Equipment}
s _{Network Servers}
DESCRIPTIO
The LTC^®2900 is a programmable supply monitor for
systems with up to four supply voltages. One of 16 preset
or adjustable voltage monitor combinations can be se-
lected using an external resistor divider connected to the
program pin. The preset voltage thresholds are accurate
to ±1.5% over temperature.
The reset delay time is adjustable using an external
capacitor and the manual reset input may be used with a
momentary switch to issue reset pulses with programmed
duration. Tight voltage threshold accuracy and glitch
immunity ensure reliable reset operation without false
triggering. The RST output is guaranteed to be in the
correct state for V_CC down to 1V. The LTC2900-1 features
an open-drain RST output, while the LTC2900-2 has a
push-pull RST output.
The 43µA supply current makes the LTC2900 ideal for
power conscious systems and it may be configured to
monitor less than four inputs. The parts are available in
the 10-lead MSOP and the 10-lead 3mm × 3mm DFN
packages.
, LTC and LT are registered trademarks of Linear Technology Corporation.
TYPICAL APPLICATIO
Quad Supply Monitor (5V, 3.3V, 2.5V, 1.8V)
5V
3.3V
DC/DC
CONVERTER
2.5V
1.8V
SYSTEM
LOGIC
C1
0.1µF
C2
0.1µF
R1
59k
1%
R2
40.2k
1%
V3 V4
V1
LTC2900-2
V2
V_REF
V_PG
GND
RST
PBR
CRT
PUSH-BUTTON
C_RT
47nF
RESET
2900 TA01
t_RST = 216ms
2900f
1