AME, Inc.
AME8510 / 8520 / 8530
Micropower
µ
P Watch Dog Timer
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General Description
The AME8510/8520/8530 family allows the user to cus-
tomize the CPU monitoring function without any external
components. The user has a large choice of reset volt-
age thresholds and output driver configurations, all of
which are preset at the factory. Each wafer is trimmed
to the customer's specifications.
These circuits will ignore fast negative going transients
on V
DD
. The state of the reset output is guaranteed to be
correct down to 1V.
After V
DD
crosses above a factory preset threshold,
the AME8510/8520/8530 assert a reset signal. After a
predetermined time (the “reset” interval) the reset is
deasserted. If V
DD
ever drops below the threshold voltage
a reset is asserted immediately. In addition to a supply
monitoring function the AME8510/8520 also monitor tran-
sitions at the watch dog (WDI) input. If a logic transition
does not occur at the WDI pin within a certain time inter-
val (the “watchdog” interval) then a reset is asserted. The
reset deasserts after the reset interval, as explained ear-
lier.
The AME8510/8530 can both assert a reset manually
by pulling the MRB input to ground.
Space saving SOT-25 packages and micropower qui-
escent current make this family a natural for portable
battery powered equipment.
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Applications
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Motherboards
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Computer peripherals
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Portable electronics
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Applications using CPUs
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Consumer electronics
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Pin Configuration
SOT-25
Top View
5
4
AME8510
1. Reset/ResetB
2.
3.
4.
5.
GND
MRB
WDI
V
DD
AME8510
1
2
3
SOT-25
Top View
5
4
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Features
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Small packages: SOT-25
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7 voltage threshold options
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Tight voltage threshold tolerance ---±1.50%
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12 output driver configuration options
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Wide temperature range -------- -40
o
C to 85
o
C
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Low temperature coefficient --- 100ppm/
o(max)
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Low quiescent current < 3.0µA
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3 bonding options
AME8520
AME8520
1. Reset/ResetB
2. GND
3. ResetB/Reset
4. WDI
5. V
DD
1
2
3
SOT-25
Top View
5
4
AME8530
AME8530
1. Reset/ResetB
2. GND
3. ResetB/Reset
4. MRB
5. V
DD
1
2
3
1
AME [ ANALOG MICROELECTRONICS ]
