November 2006
rev 1.4
ASM1233D-L/D/M
Low Power, 5V/3.3V, µP Reset, Active LOW, Open-Drain Output
Applications
•
•
•
•
•
•
•
Set-top boxes
Cellular phones
PDAs
Energy management systems
Embedded control systems
Printers
Single board computers
General Description
The ASM1233D-L/1233D/1233M are voltage supervisors with
low-power, 5/3.3V µP Reset, with an active LOW, open-drain
output. Maximum supply current over temperature is 15µA for
3.3V devices and 20µA for 5V devices.
The ASM1233D-L/1233D/1233M generates an active LOW
reset signal whenever the monitored supply is out of tolerance.
A precision reference and comparator circuit monitors power
supply (V
CC
) level. The tolerance are 5%,10% and 15%. When
an out-of-tolerance condition is detected, an internal power-fail
signal is generated which forces an active LOW reset signal.
After V
CC
returns to an in-tolerance condition, the reset signal
remains active for 350ms to allow the power supply and system
microprocessor to stabilize.
The ASM1233D-L/1233D/1233M is designed with an open-
drain output stage and operates over the extended industrial
temperature range. These devices are available in compact
SOT-223, SO-8 and TO-92 packages.
Other low power products in this family include ASM1810/11/
12/15/16/17.
Typical Operating Circuit
V
CC
ASM1233D-L/D/M
Microprocessor
RESET
RESET
GND
Block Diagram
Key Features
•
•
•
•
•
•
•
•
Low Supply Current
• 15µA maximum (<=3.6V), 20µA maximum (5.5V)
Automatically restarts a microprocessor after power failure
350ms reset delay after V
CC
returns to an in-tolerance con-
dition
Active LOW power-up reset, 5kΩ internal pull-up
Precision temperature-compensated voltage reference and
comparator
Eliminates external components
Low-cost SOT-223/SO-8/TO-92 packages
Operating temperature: -40°C to +85°C
Reference
Supply
Tolerance
Bias
ASM1233D-L,ASM1233D,ASM1233M
V
CC
5.0kΩ
+
RESET
Delay
350ms
Typical
-
GND
PulseCore Semiconductor Corporation
1715 S. Bascom Ave Sutie 200, Campbell, CA95008 . Tel: 408-879-9077 . Fax: 408-.879-9018 . www.pulsecoresemi.com
Notice: The information in this document is subject to change without notice
November 2006
rev 1.4
ASM1233D-L/D/M
Pin Configuration
SOT-223
RESET
GND
V
CC
2
4
3
RESET
ASM1233D-L
ASM1233D
SO-8
1
2
3
4
ASM1233M
TO-92
8
7
6
5
NC
NC
NC
NC
ASM1233D-L
ASM1233D
ASM1233M
V
CC
1
GND
NC
GND
1
2
3
Pin Description
Pin#
TO-92
ASM1233D-L
ASM1233D
1
2
3
-
TO-92
ASM1233M
3
1
2
-
Pin Name
SO-8
SOT-223
Description
4
1
2
3,5,6,7&8
1,4
2
3
-
GND
RESET
V
CC
NC
Ground.
Active LOW reset output.
Power supply input.
No connection
Low Power, 5V/3.3V, µP Reset, Active LOW, Open-Drain Output
Notice: The information in this document is subject to change without notice
2 of 11
November 2006
rev 1.4
ASM1233D-L/D/M
Application Information
Operation - Power Monitor
The ASM1233D-L/1233D/1233M detects out-of-tolerance
power supply conditions. It resets a processor during power-
up, power-down and generates a reset to the system
processor when the monitored power supply voltage is below
the reset threshold. When an out-of-tolerance V
CC
voltage is
detected, the RESET signal is asserted. On power-up,
RESET is kept active (LOW) for approximately 350ms after
the power supply voltage has reached the selected tolerance.
This allows the power supply and microprocessor to stabilize
before RESET is released.
V
CC
V
HTL
V
CCTP
t
F
V
LTL
RESET
t
RPD
V
OL
t
R
V
HTL
V
LTL
V
CCTP
Figure 2: Timing Diagram: Power-Down
V
CC
t
RPU
V
OH
RESET
Figure 1: Timing Diagram: Power-Up
~
~
3 of 11
~
~
~
~
Low Power, 5V/3.3V, µP Reset, Active LOW, Open-Drain Output
Notice: The information in this document is subject to change without notice
November 2006
rev 1.4
ASM1233D-L/D/M
Absolute Maximum Ratings
Parameter
Voltage on V
CC
Voltage on RESET
Operating Temperature Range
Soldering Temperature (for 10 sec)
Storage Temperature
ESD rating
HBM
MM
2
200
KV
V
-55
Min
-0.5
-0.5
-40
Max
7
V
CC
+ 0.5
85
260
125
Unit
V
V
°C
°C
°C
NOTE: These are stress ratings only and functional use is not implied. Exposure to absolute maximum ratings for prolonged
periods of time may affect device reliability.
Low Power, 5V/3.3V, µP Reset, Active LOW, Open-Drain Output
Notice: The information in this document is subject to change without notice
4 of 11
November 2006
rev 1.4
ASM1233D-L/D/M
Electrical Characteristics
Unless otherwise noted, V
CC
= 5V+10% and specifications are over the operating temperature range of -40°C to +85°C.
All voltages are referenced to ground.
Parameter
Supply Voltage
Output Voltage
Output Current
Operating Current
Symbol
V
CC
V
OL
V
OH
I
OL
I
CC
RESET asserted
I
OUT
< 500 µA
Output = 0.4V
V
CC
< 5.5V, RESET output open
V
CC
< =3.6V, RESET output open
ASM1233D-LZ-5
ASM1233D-LZ-10
ASM1233D-LZ-15
ASM1233DZ-5
V
CC
Trip Point
V
CCTP
ASM1233DZ-10
ASM1233DZ-15
ASM1233M-5
ASM1233M-55
ASM1233M-3
ASM1233D, ASM1233MS-5,
ASM1233MS-55
ASM1233MS-3
ASM1233D-L
ASM1233D, ASM1233MS-5,
ASM1233MS-55
ASM1233MS-3
ASM1233D-L
Internal Pull-up Resistor
Output Capacitance
V
CC
Detect to RESET Low
V
CC
Detect to RESET High
V
CC
Slew Rate
(V
HTL
- V
LTL
)
V
CC
Slew Rate
(V
LTL
- V
HTL
)
R
P
C
OUT
t
RPD
t
RPU
t
F
t
R
ASM1233D-L, ASM1233M
ASM1233D
200
250
300
0
2
350
350
3.5
5.0
2.98
2.8
2.64
4.5
4.25
4.0
4.25
4.5
2.64
Conditions
Min
1.2
-
V
CC
-0.5V
8
8
6
3.06
2.88
2.72
4.625
4.375
4.125
4.375
4.625
2.72
20
µA
15
3.15
2.97
2.8
4.74
4.49
4.24
4.49
4.75
2.8
4.75
3.14
3.06
4.00
2.48
2.3
7.5
10
10
500
450
kΩ
pF
µs
ms
µs
ns
V
V
V
-
V
CC
-0.1V
Typ
Max
5.5
0.4
Unit
V
V
mA
Voltage High Trip Level
V
HTL
Voltage Low Trip Level
V
LTL
Note: A 1kΩ resistor maybe required in some applications for proper operation of the microprocessor reset control circuit.
Low Power, 5V/3.3V, µP Reset, Active LOW, Open-Drain Output
Notice: The information in this document is subject to change without notice
5 of 11