AME, Inc.
1
AME8500 / 8501
µµ
µµ
µProcessor Supervisory
l Small packages: SOT-23, SOT-89
l 11 voltage threshold options
l Tight voltage threshold tolerance ---±1.50%
l 5 reset interval options
l 4 output configuration options
l Wide temperature range -------- -40
o
C to 85
o
C
l Low temperature coefficient --- 100ppm/
o
C(max)
l Low quiescent current < 3.0µA
l Thermal shutdown option (AME8501)
The AME8500 family allows the user to customize the
CPU reset function without any external components.
The user has a large choice of reset voltage thresholds,
reset time intervals, and output driver configurations, all
of which are preset at the factory. Each wafer is trimmed
to the customer's specifications.
These circuits monitor the power supply voltage of µP
based systems. When the power supply voltage drops
below the voltage threshold a reset is asserted immedi-
ately (within an interval T
D1
). The reset remains asserted
after the supply voltage rises above the voltage threshold
for a time interval, T
D2
. The reset output may be either
active high (RESET) or active low (RESETB). The reset
output may be configured as either push/pull or open
drain. The state of the reset output is guaranteed to be
correct for supply voltages greater than 1V.
The AME8501 includes all the above functionality plus
an overtemperature shutdown function. When the ambi-
ent temperature exceeds 80
o
C a reset is asserted and
remains asserted until the temperature falls below 60
o
C.
Space saving SOT23 packages and micropower qui-
escent current (<3.0µA) make this family a natural for
portable battery powered equipment.
n General Description
n Features
n Typical Operating Circuit
Note: * External pull-up resistor is required if open-
drain output is used. 10 kΩ is recommended.
n Block Diagram
l Portable electronics
l Power supplies
l Computer peripherals
l Data acquisition systems
l Applications using CPUs
l Consumer electronics
n Applications
AME8500 with Push-Pull RESET
RESET
V
DD
GND
R1
R2
I1
V
REF
P1
N1
Delay
V
DD
GND
R1
R2
I1
V
REF
P1
N1
RESET
Delay
AME8500 with Push-Pull RESET
Processor
V
CC
GND
RESET
Input
AME8500
V
CC
GND
RESET / RESET
2
3
*
