AMSCO AS1904

austriamicrosystems
AS1904, AS1905, AS1906
D a ta S he e t
U l t r a L o w - P o w e r µP S u p e r v i s o r y C i r c u i t
1 General Description
2 Key Features
The AS1904/5/6 family is an ultra low-power supervisory
circuit device.
The device can be used to monitor the supply voltage of
digital systems and microprocessors and initiate a reset
when the voltage goes below a predefined threshold.
The duration of the reset is 5/20/100/500ms (typ.) after
the supply voltage has risen above the threshold.
„
Low 150nA (typical) Supply Current
„
Precision Monitoring of 2.5-, 3-, and 3.3V-Power
Supplies
„
Supply Voltage Range 1.0 to 3.6V
„
Reset Threshold Available from 2.2 to 3.1V
„
Available in three Versions
The device exhibits excellent reliability and can reduce
application costs by eliminating all external components.
- AS1904 Push-Pull RESETN
- AS1905 Push-Pull RESET
The device is available with different output drivers:
- AS1906 Open Drain RESETN
„
The AS1904 has a push-pull driver with an active low
reset.
„
The AS1905 uses the same output stage as the
AS1904, but has an active high reset.
„
The AS1906 has an open drain output with active low
reset.
All devices operate down to a voltage of 1V.
The reset thresholds are factory-trimmable between
2.2V and 3.08V in steps of approximately 100mV.
Each device of the AS1904/5/6 family is offered with four
time-out periods of 5/20/100/500ms.
The extremely low current consumption of only 150nA
(typ) at 3.3V makes the device ideal for use in portable
applications.
All devices are available in a 3-pin SOT23 package.
„
4 Time-Out Periods Ranging from 5 to 500ms
„
Detection Voltage Accuracy: ±1.5%
„
Temperature Range: -40 to +85°C
„
SOT23-3 Package
„
Pin Compatible to MAX6326/6327/6328
„
Superior Upgrade to austriamicrosystems
AS1901/2/3 Device Family
3 Applications
Wo
W
orrlldd’s
s LLow
Po’w
ow es
Co P
C
onnssuomweerr estt
um pti
ptioon!
n!
„
Computers
„
Intelligent Instruments
„
Controllers
„
Critical Microprocessor and Microcontroller
Power Monitoring
„
Portable/Battery-Powered Equipment
„
Automotive
Figure 1. Functional Block Diagrams
VCC
VCC
3
3
VDD
VCC
AS1904
AS1905
RESET,
RESETN
VDD
AS1906
Microprocessor
2
GND
RESET
RESETN
GND
GND
1
www.austriamicrosystems.com
VCC
Microprocessor
2
RESET I/O
GND
1
Revision 1.4
1-9
austriam i c r o systems
AS1904, AS1905, AS1906
Data Sheet
4 Absolute Maximum Ratings
Stresses beyond those listed in Table 1 may cause permanent damage to the device. These are stress ratings only,
and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may
affect device reliability.
Table 1. Absolute Maximum Ratings (TA = 25°C Unless Otherwise Noted)
Parameter
Limits
Units
VDD to GND
-0.3 to +5
V
RESET/RESETN to GND
-0.3 to VDD + 0.3
V
Input Current (VDD)
20
mA
Output Current (RESET, RESETN)
20
mA
Rate of Rise (VDD)
100
V/µs
Operating Temperature Range (TA)
-40 to +85
°C
Storage Temperature Range
-65 to +150
°C
Package-Body Peak Temperature
www.austriamicrosystems.com
+260
°C
Revision 1.4
Notes
The reflow peak soldering temperature (body
temperature) specified is in accordance with
IPC/JEDEC J-STD-020C “Moisture/Reflow
Sensitivity Classification for non-hermetic
Solid State Surface Mount Devices”
2-9
austriam i c r o systems
AS1904, AS1905, AS1906
Data Sheet
5 Electrical Characteristics
VDD = Full Range; TA = -40º to +85°C; Unless Otherwise Specified
Table 2. Electrical Characteristics
Parameter
Symbol
VDD Range
VDD
Supply Current
IDD
RESET Threshold Voltage1
VDD to Reset Delay2
RESET Active Time-Out Period3
Conditions
Min
TA = 0 to +70°C
1.0
TA = -40 to +85°C
1.2
VDD = 3.3V, No Load
VOL
RESETN Output Voltage (AS1904)
VOH
VOH
RESET Output Voltage (AS1905)
VOL
RESET Threshold Hysteresis
VHYST
Open-Drain RESETN Output
Leakage Current (AS1906)
ILEAK
Unit
3.6
V
3.6
V
150
290
nA
VTH 1.5%
VTH
VTH +
1.5%
V
TA = -40 to +85°C
VTH 2.5%
VTH
VTH +
2.5%
V
20
50
µs
tTP
tTP +
60%
ms
ISINK = 1.2mA, VDD = 2.1V,
reset asserted
0.4
V
ISINK = 400µA, VDD = 1.2V,
reset asserted
0.4
V
VDD = VTH to (VTH - 100mV)
tTP 40%
tTP
RESETN Output Voltage
(AS1904/AS1906)
Max
TA = +25°C
VTH
tRD
Typ
ISOURCE = 1.2mA, VDD = 3.2V
0.8 x
VDD
V
ISOURCE = 500µA, VDD = 2.1V,
reset asserted
0.8 x
VDD
V
ISOURCE = 100µA, VDD = 1.2V,
reset asserted
0.8 x
VDD
V
ISINK = 1.2mA, VDD = 3.2V,
reset not asserted
0.4
10
V
mV
0.1
µA
Notes:
1
See Table 5, “Coding of Factory-Trimmed Reset Threshold Voltages,” on page 5.
2
Guaranteed by design.
3
See Table 3, “Coding of Factory-trimmed Reset Active Time-Out Period,” on page 5.
www.austriamicrosystems.com
Revision 1.4
3-9
austriam i c r o systems
AS1904, AS1905, AS1906
Data Sheet
Interfacing to Microprocessors with Bi-Directional Reset Pins
6 Operation
6.1 Interfacing to Microprocessors with Bi-Directional Reset Pins
The device has an open drain RESETN output, which enables easy interfacing to microprocessors (µP) with bi-directional reset pins, such as the Motorola 68HC11. The RESETN pin of the microcontroller (µC) can be connected directly
to the µP supervisor's RESETN output with a single pull-up resistor (see Figure 1 on page 1).
6.2 Operating Characteristics
Supply Current vs. Temperature VCC = 3.3V
P o w er-D o w n R es et D elay
vs . T e m p era tu re V O D = 10m V
0.5
200
0.4
Reset Delay (µs)
Supply Current (µA)
150
0.3
0.2
100
50
0.1
0
-40
0
-20
0
20
40
60
-4 0
80
-2 0
0
Power-Up Reset Timeout
vs. Temperature
40
60
80
Maximum Transient Duration
vs. Reset Threshold Overdrive
200
400
Maximum Transient Duration (µs)
POWER-UP RESET TIMEOUT (ms)
20
T e mpe rature (°C )
Temperature (°C)
160
120
80
40
300
200
100
0
0
-40
-20
0
20
40
60
80
1
10
100
1000
Reset Threshold Overdrive
Vth-Vcc (mV)
Temperature (°C)
6.3 Negative-Going VDD Transients
The device is optimized to ignore short-duration, negative-going VDD transients (glitches) in order to avoid incorrect
resets.
In the graph Maximum Transient Duration vs. Reset Threshold Overdrive (page 4) , the conditions are shown, for
which the reset pulses are not generated. In the graph the maximum pulse width that a negative VDD transient may
have when a reset signal is generated. As the amplitude of the transient increases, the maximum allowable pulse width
decreases.
www.austriamicrosystems.com
Revision 1.4
4-9
austriam i c r o systems
AS1904, AS1905, AS1906
Data Sheet
7 Options
Table 3. Coding of Factory-trimmed Reset Active Time-Out Period
Device
tTP in Milliseconds
Suffix
Min
Typ
Max
AS190x_xx
A
3
5
8
AS190x_xx
B
12
20
32
AS190x_xx
C
60
100
160
AS190x_xx
D
300
500
800
Table 4. Output Variants
Device
Output Functionality
AS1904xxx
Active Low (RESETN)
AS1905xxx
Active High (RESET)
AS1906xxx
Open Drain (RESETN)
Table 5. Coding of Factory-Trimmed Reset Threshold Voltages
Reset Threshold Voltage, VTH in V
Device
Suffix
TA = +25°C
Min
TA = -40 to +85°C
Typ
Max
Min
Max
AS190xx__
22
2.167
2.2
2.233
2.145
2.255
AS190xx__
23
2.285
2.32
2.355
2.262
2.378
AS190xx__
24
2.364
2.4
2.436
2.340
2.460
AS190xx__
25
2.463
2.5
2.538
2.438
2.563
AS190xx__
26
2.591
2.63
2.669
2.564
2.696
AS190xx__
27
2.660
2.7
2.741
2.633
2.768
AS190xx__
28
2.758
2.8
2.842
2.730
2.870
AS190xx__
29
2.886
2.93
2.974
2.857
3.003
AS190xx__
30
2.955
3.0
3.045
2.925
3.075
AS190xx__
31
3.034
3.08
3.126
3.003
3.157
www.austriamicrosystems.com
Revision 1.4
5-9
austriam i c r o systems
AS1904, AS1905, AS1906
Data Sheet
Pin Assignments
8 Pinout and Packaging
8.1 Pin Assignments
Figure 2. Pin Assignments (Top View)
Top View
GND
1
AS1904
AS1905
AS1906
RESETN,
RESET
3
VDD
2
SOT23-3
8.2 Pin Descriptions
Table 6. Pin Descriptions
Pin Number
AS1904/AS1906
AS1905
1
1
Pin Name
Description
GND
Ground
2
-
RESETN
Active-low reset output. RESETN remains low while VDD is
below the reset threshold and for tTP after VDD rises above
the reset threshold. RESETN is open-drain on the AS1906
and push-pull on the AS1904.
-
2
RESET
Active-high reset output. RESET remains high while VDD is
below the reset threshold and for tTP after VDD rises above
the reset threshold.
3
3
VDD
Supply voltage.
www.austriamicrosystems.com
Revision 1.4
6-9
austriam i c r o systems
AS1904, AS1905, AS1906
Data Sheet
Package Drawings and Markings
8.3 Package Drawings and Markings
The device is available in a 3-pin SOT-23 package.
Figure 3. 3-Pin SOT-23 Package.
www.austriamicrosystems.com
Revision 1.4
7-9
austriam i c r o systems
AS1904, AS1905, AS1906
Data Sheet
9 Ordering Information
The device is available in the following standard versions.
Standard Part
Threshold (V)
Duration (mS)
Marking
AS1904C23
2.32
100
ASGI
AS1904C26
2.63
100
ASDB
AS1904C31
3.08
100
ASDG
AS1905C23
2.32
100
ASDI
AS1905C26
2.63
100
ASDL
AS1905C31
3.08
100
ASDQ
AS1906C23
2.32
100
ASDS
AS1906C26
2.63
100
ASDV
AS1906C28
2.8
100
ASDX
AS1906C31
3.08
100
ASGK
Non-standard versions require a minimum order of 30,000 units. Contact austriamicrosystems for availability of nonstandard versions.
www.austriamicrosystems.com
Revision 1.4
8-9
austriam i c r o systems
AS1904, AS1905, AS1906
Data Sheet
Copyrights
Copyright © 1997-2005, austriamicrosystems AG, Schloss Premstaetten, 8141 Unterpremstaetten, Austria-Europe.
Trademarks Registered ®. All rights reserved. The material herein may not be reproduced, adapted, merged, translated, stored, or used without the prior written consent of the copyright owner.
All products and companies mentioned are trademarks or registered trademarks of their respective companies.
Disclaimer
Devices sold by austriamicrosystems AG are covered by the warranty and patent indemnification provisions appearing
in its Term of Sale. austriamicrosystems AG makes no warranty, express, statutory, implied, or by description regarding
the information set forth herein or regarding the freedom of the described devices from patent infringement. austriamicrosystems AG reserves the right to change specifications and prices at any time and without notice. Therefore, prior
to designing this product into a system, it is necessary to check with austriamicrosystems AG for current information.
This product is intended for use in normal commercial applications. Applications requiring extended temperature
range, unusual environmental requirements, or high reliability applications, such as military, medical life-support or lifesustaining equipment are specifically not recommended without additional processing by austriamicrosystems AG for
each application.
The information furnished here by austriamicrosystems AG is believed to be correct and accurate. However,
austriamicrosystems AG shall not be liable to recipient or any third party for any damages, including but not limited to
personal injury, property damage, loss of profits, loss of use, interruption of business or indirect, special, incidental or
consequential damages, of any kind, in connection with or arising out of the furnishing, performance or use of the technical data herein. No obligation or liability to recipient or any third party shall arise or flow out of
austriamicrosystems AG rendering of technical or other services.
Contact Information
Headquarters
austriamicrosystems AG
A-8141 Schloss Premstaetten, Austria
Tel: +43 (0) 3136 500 0
Fax: +43 (0) 3136 525 01
e-mail: [email protected]
For Sales Offices, Distributors and Representatives, please visit:
http://www.austriamicrosystems.com
austriamicrosystems
www.austriamicrosystems.com
Revision 1.4
– a leap ahead
9-9