MAXIM DS1815 User Manual
www.maxim-ic.com
3
DS1815
3.3V EconoReset with Push-Pull Output
FEATURES
§ Automatically restarts a microprocessor after
power failure
§ Maintains reset for 150ms after VCC returns to
an in-tolerance condition
§ Reduces need for discrete components
§ Precision temperature-compensated voltage
reference and voltage sensor
§ Accurate 5%, 10% or 20% power monitoring
§ Low-cost TO-92 or space saving surface-
mount SOT-23 packages available
§ Push-pull output for low current operation
§ Operating temperature -40°C to +85°C
PIN ASSIGNMENT
DALLAS
DS1815
Econo
Reset
12
TOP VIEW
SOT-23 PACKAGE
See Mech.
Drawings Section
1 2 3
1 2 3
BOTTOM VIEW
TO-92 PACKAGE
See Mech.
Drawings Section
On Website
On Website
PIN DESCRIPTION
TO-92
1 RST Active Low Reset Output
2 VCC Power Supply
3 GND Ground
SOT-23
1 RST Active Low Reset Output
2 V
Power Supply
CC
3 GND Ground
DESCRIPTION
The DS1815 EconoReset uses a precision temperature reference and comparator circuit to monitor the
status of the power supply (V
signal is generated which forces reset to the active state. When VCC returns to an in-tolerance condition,
the reset signal is kept in the active state for approximately 150ms to allow the power supply and
processor to stabilize.
). When an out-of-tolerance condition is detected, an internal power-fail
CC
1 of 5 041002
DS1815
OPERATION — POWER MONITOR
The DS1815 provides the functions of detecting out-of-tolerance power supply conditions and warning a
processor-based system of impending power failure. When VCC is detected as out of tolerance, the RST
signal is asserted. On power-up, RST is kept active for approximately 150ms after the power supply has
reached the selected tolerance. This allows the power supply and microprocessor to stabilize before RST
is released.
BLOCK DIAGRAM (CMOS OUTPUT) Figure 1
APPLICATION EXAMPLE Figure 2
APPLICATION DIAGRAM:
RST VALID TO 0 VOLTS V
ON THE DS1815 Figure 3
CC
2 of 5
Loading...