AS1910 Datasheet, PDF (1/2 Pages) ams AG – Dual-Voltage Microprocessor Supervisory Circuits with Reset and Watchdog

austriamicrosystems
AS1910 - AS1915
Dual-Voltage Microprocessor Supervisory Circuits
with Reset and Watchdog
Product Brief
1 General Description
2 Key Features
The AS1910 - AS1915 microprocessor supervisory cir-
cuits were designed to generate a reset when one of the
two monitored supply voltages falls below a factory-
trimmed threshold, and to maintain the reset for a mini-
mum timeout period when both supplies are above their
reset thresholds. Guaranteed to be in the correct state
for VCC higher than +1.0V, these devices are ideal for
multiple-voltage systems with strict monitoring require-
ments.
The AS1913/AS1914/AS1915 feature factory-trimmed
thresholds to monitor a primary voltage between 1.8 and
3.6V, and a secondary voltage between 0.9 and 2.5V.
For the AS1910/AS1911/AS1912, a secondary monitor-
ing voltage can be user-adjusted via an external resistor
divider down to 0.6V.
The devices are available with the reset output types
listed in Table 1.
Table 1. Standard Products
Model
Reset Output Type
AS1910/AS1913
Active-Low Push/Pull
AS1911/AS1914
Active-High Push/Pull
AS1912/AS1915
Active-Low Open-Drain
The AS1910 - AS1915 include a manual-reset input for
systems that never fully power down the microproces-
sor. Additionally, these devices feature a watchdog timer
to help ensure that the processor is operating within
proper code boundaries.
The AS1910 - AS1915 are available in a 6-pin SOT23
package.
! Primary VCC Supervisory Range: +1.8 to +3.6V
! Secondary VCC Supervisory Range: +0.9 to +2.5V
(AS1913/AS1914/AS1915)
! User-Adjustable Threshold Down to +0.63V
(AS1910/AS1911/AS1912)
! Guaranteed Reset Valid Down to VCC = +1.0V
! Reset Timeout Delay: 215ms
! Manual Reset Input
! Three Reset Output Types
- Active-High Push/Pull
- Active-Low Push/Pull
- Active-Low Open-Drain
! Watchdog Timeout Period: 1.5s
! Immune to Fast Negative VCC Transients
! External Components Not Required
! 6-pin SOT23 Package
3 Applications
The devices are ideal for portable and battery-powered
systems, embedded controllers, intelligent instruments,
automotive systems, critical CPU monitoring, and any
multi-supply application.
Figure 1. Typical Application Diagram
VCC
VCC2
External
Reset
6
VCC
5
VCC2
3
MRN
AS1913/
AS1915
1
RESETN
4
WDI
GND 2
I/O Supply
Core
Supply
RESETN
CPU
GND
I/O
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Revision 0.3
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