ASM708CSA [PULSECORE]
Low Power μP Supervisor Circuits; 低功耗μP监控电路
| 型号： | ASM708CSA |
| 厂家： | 
PulseCore Semiconductor |
| 描述： | Low Power μP Supervisor Circuits |
| 文件： | 总15页 (文件大小：281K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
ASM705/706/707/708
ASM813L
April 2008
rev 1.6
Low Power µP Supervisor Circuits
General Description
Features
The ASM705 / 706 / 707 / 708 and ASM813L are cost
effective CMOS supervisor circuits that monitors power-
supply and battery voltage level, and µP/µC operation.
•
Precision power supply monitor
• 4.65V threshold (ASM705/707/813L)
• 4.40V threshold (ASM706/708)
Debounced manual reset input
Voltage monitor
•
•
The family offers several functional options. Each device
generates a reset signal during power-up, power-down and
during brownout conditions. A reset is generated when
the supply drops below 4.65V (ASM705/707/813L) or
4.40V (ASM706/708). For 3V power supply applications,
refer to the ASM705P/R/S/T data sheet. In addition, the
ASM705/706/813L feature a 1.6 second watchdog timer.
The ASM707/708 have both active-HIGH and active-LOW
reset outputs but no watchdog function. The ASM813L
has the same pin-out and functions as the ASM705 but has
an active-HIGH reset output. A versatile power-fail circuit
has a 1.25V threshold, useful in low battery detection and
for monitoring non-5V supplies. All devices have a manual
reset (MR) input. The watchdog timer output will trigger
a reset if connected to MR.
• 1.25V threshold
• Battery monitor / Auxiliary supply monitor
Watchdog timer (ASM705/706/813L)
200ms reset pulse width
•
•
•
•
Active HIGH reset output (ASM707/708/813L)
MicroSO package
Application
•
•
•
•
•
•
•
Computers and embedded controllers
Portable/Battery-operated systems
Intelligent instruments
Wireless communication systems
PDAs and hend-held equipment
Automative Systems
Safety Systems
All devices are available in 8-pin DIP, SO and MicroSO
packages.
Typical Operating Circuit
PulseCore Semiconductor Corporation
1715 S. Bascom Ave Suite 200 Campbell, CA 95008 • Tel: 408-879-9077 • Fax: 408-879-9018
www.pulsecoresemi.com
Notice: The information in this document is subject to change without notice.
ASM705/706/707/708
ASM813L
April 2008
rev 1.6
Block Diagram
Pin Configuration
Low Power µP Supervisor Circuits
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Notice: The information in this document is subject to change without notice.
ASM705/706/707/708
ASM813L
April 2008
rev 1.6
Pin Description
Pin Number
ASM707/708
ASM705/706
ASM813L
Name
Function
DIP/
DIP/
SO
DIP/
SO
MicroSO
SO
MicroSO
MicroSO
Manual reset input. The active LOW input
triggers a reset pulse. A 250 µA pull-up
current allows the pin to be driven by
TTL/CMOS logic or shorted to ground with a
switch.
MR
1
3
1
3
1
3
2
3
4
5
2
3
4
5
2
3
4
5
VCC
+5V power supply input.
GND
Ground reference for all signals.
Power-fail input voltage monitor. With PFI
less than 1.25V, PFO goes LOW. Connect
PFI to Ground or VCC when not in use.
Power-fail output. The output is active LOW
and sinks current when PFI is less than
1.25V.
4
5
6
7
4
5
6
7
4
5
6
7
PFI
PFO
Watchdog input. WDI controls the internal
watchdog timer. A HIGH or LOW signal for
1.6sec at WDI allows the internal timer to
run-out, setting WDO LOW. The watchdog
function is disabled by floating WDI or by
connecting WDI to a high impedance three-
state buffer. The internal watchdog timer
clears when: RESET is asserted; WDI is
three-stated ; or WDI sees a rising or falling
edge.
6
8
-
-
6
8
WDI
NC
-
-
6
7
8
1
-
-
-
-
Not Connected.
Active LOW reset output. Pulses LOW for
200ms when triggered, and stays LOW
whenever VCC is below the reset threshold.
RESET remains LOW for 200ms after VCC
7
1
RESET rises above the reset threshold or MR goes
from LOW to HIGH. A watchdog timeout will
not trigger RESET unless WDO is
connected to MR.
Watchdog output. WDO goes LOW when
the 1.6 second internal watchdog timer
times-out and does not go HIGH until the
watchdog is cleared. In addition, when VCC
8
-
2
-
-
-
8
7
2
1
WDO
falls below the reset threshold, WDO goes
LOW. Unlike RESET, WDO does not have a
minimum pulse width and as soon as VCC
exceeds the reset threshold, WDO goes
HIGH with no delay.
Active HIGH reset output. The inverse of
8
2
RESET RESET. The ASM813L only has a RESET
output.
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Notice: The information in this document is subject to change without notice.
ASM705/706/707/708
ASM813L
April 2008
rev 1.6
Detailed Description
A
proper reset input enables a microprocessor /
microcontroller to start in a known state. ASM70X and
ASM813L assert reset to prevent code execution errors
during power-up, power-down and brown-out conditions.
RESET/RESET Timing
The RESET/RESET signals are designed to start a
µP/µC in a known state or return the system to a known
state.
The ASM707/708 have two reset outputs, one active-
HIGH RESET and one active-LOW RESET output. The
ASM813L has only an active-HIGH output. RESET is
simply
the
complement
of
RESET.
Manual Reset (MR)
RESET is guaranteed to be LOW with VCC above 1.2V.
During a power-up sequence, RESET remains low until
the supply rises above the threshold level, either 4.65V or
4.40V. RESET goes high approximately 200ms after
crossing the threshold.
The active-LOW manual reset input is pulled high by a
250µA pull-up current and can be driven low by
CMOS/TTL logic or a mechanical switch to ground. An
external debounce circuit is unnecessary since the
140ms minimum reset time will debounce mechanical
pushbutton switches.
During power-down, RESET goes LOW as VCC falls
below the threshold level and is guaranteed to be under
0.4V with VCC above 1.2V.
By connecting the watchdog output (WDO) and MR, a
watchdog timeout forces RESET to be generated. The
ASM813L should be used when an active-HIGH RESET
is required.
In a brownout situation where VCC falls below the
threshold level, RESET pulses low. If a brown-out occurs
during an already initiated reset, the pulse will continue
for a minimum of 140ms.
Watchdog Timer
The watchdog timer available on the ASM705/706/813L
monitors µP/µC activity. An output line on the processor
is used to toggle the WDI line. If this line is not toggled
within 1.6 seconds, the internal timer puts the watchdog
output, WDO, into a LOW state. WDO will remain LOW
until a toggle is detected at WDI.
Power Failure Detection With Auxiliary Comparator
All devices have an auxiliary comparator with 1.25V trip
point and uncommitted output (PFO) and noninverting
input (PFI). This comparator can be used as a supply
voltage monitor with an external resistor voltage divider.
The attenuated voltage at PFI should be set just below
the 1.25 threshold. As the supply level falls, PFI is
reduced causing the PFO output to transit LOW. Normally
PFO interrupts the processor so the system can be shut
down in a controlled manner.
If WDI is floated or connected to a three-stated circuit, the
watchdog function is disabled, meaning, it is cleared and
not counting. The watchdog timer is also disabled if
RESET is asserted. When RESET becomes inactive and
the WDI input sees a high or low transition as short as
50ns, the watchdog timer will begin a 1.6 second
countdown. Additional transitions at WDI will reset the
watchdog timer and initiate a new countdown sequence.
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Notice: The information in this document is subject to change without notice.
ASM705/706/707/708
ASM813L
April 2008
rev 1.6
WDO will also become LOW and remain so, whenever
the supply voltage, VCC , falls below the device threshold
level. WDO goes HIGH as soon as VCC transitions above
the threshold. There is no minimum pulse width for WDO
as there is for the RESET outputs. If WDI is floated, WDO
essentially acts as a low-power output indicator.
Monitoring Voltages Other Than VCC
The ASM705-708 can monitor voltages other than VCC
using the Power Fail circuitry. If a resistive divider is
connected from the voltage to be monitored to the Power
Fail input (PFI), the PFO will go LOW if the voltage at PFI
goes below 1.25V reference. Should hysteresis be
desired, connect a resistor (equal to approximately 10
times the sum of the two resistors in the divider) between
the PFI and PFO pins. A capacitor between PFI and GND
will reduce circuit sensitivity to input high-frequency
noise. If it is desired to assert a RESET for voltages other
than VCC then the PFO output is to be connected to the
MR.
Application Information
Ensuring That RESET is Valid Down to VCC = 0V
When VCC falls below 1.1V, the ASM705-708 RESET
output no longer pulls down; it becomes indeterminate.
To avoid the possibility that stray charges build up and
force RESET to the wrong state, a pull-down resistor
should be connected to the RESET pin, thus draining
such charges to ground and holding RESET low. The
resistor value is not critical. A 100kΩ resistor will pull
RESET to ground without loading it.
Bi-directional Reset Pin Interfacing
The ASM705/6/7/8 can interface with µP/µC bi-directional
reset pins by connecting a 4.7kΩ resistor in series with
the RESET output and the µP/µC bi-directional RESET
pin.
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Notice: The information in this document is subject to change without notice.
ASM705/706/707/708
ASM813L
April 2008
rev 1.6
Monitoring a Negative Voltage
The Power-Fail circuitry can also monitor a negative
supply rail. When the negative rail is OK, PFO will be
LOW, and when the negative rail is failing (not negative
enough), PFO goes HIGH (the opposite of when positive
voltages are monitored). To trigger a reset, these outputs
need to be inverted: adding the resistors and transistor as
shown achieves this. The RESET output will then have
the same sense as for positive voltages: good = HIGH,
bad = LOW. It should be noted that this circuit’s accuracy
depends on the VCC line, the PFI threshold tolerance, and
the resistors.
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Notice: The information in this document is subject to change without notice.
ASM705/706/707/708
ASM813L
April 2008
rev 1.6
Absolute Maximum Ratings
Parameter
Min
Max
Unit
Pin Terminal Voltage with Respect to Ground
-0.3
-0.3
6.0
V
V
VCC
All other inputs1
VCC + 0.3
20
20
mA
mA
Input Current at VCC and GND
Output Current: All outputs
Rate of Rise at VCC
100
V/µs
Plastic DIP Power Dissipation
(Derate 9mW/°C above 70°C)
700
mV
SO Power Dissipation
(Derate 5.9mW/°C above 70°C)
470
330
mW
MicroSO Power Dissipation
(Derate 4.1mW/°C above 70°C)
mW
Operating Temperature Range
ASM705E/706E/707E/708E/813LE
ASM705C/706C/707C/708C/813LC
Storage Temperature Range
-40
0
+85
70
°C
°C
°C
°C
-65
160
300
Lead Temperature (Soldering 10sec)
ESD rating
2
200
HBM
MM
KV
V
Note:
1. The input voltage limits of PFI and MR can be exceeded if the input current is less than 10mA.
These are stress ratings only and functional operation is not implied. Exposure to absolute maximum ratings for prolonged time periods may affect
device reliability.
Low Power µP Supervisor Circuits
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Notice: The information in this document is subject to change without notice.
ASM705/706/707/708
ASM813L
April 2008
rev 1.6
Electrical Characteristics
Unless otherwise noted, specifications are over the operating temperature range and VCC supply voltages are 2.7V to 5.5V
(ASM706P,ASM708R), 3.0 V to 5.5V (ASM706/708S), 3.15V to 5.5V (ASM706/708T) and 4.1V to 5.5.V (ASM706/708J)
SYMBOL
TYP
Parameter
Test Conditions
Min
Max
Unit
ASM705/6/7/8C
ASM813L
ASM705/6/7/8E, ASM813E
ASM705/706C/813LC
ASM705E/706E/813LE
ASM707C/708C
1.2
1.1
1.2
5.5
5.5
5.5
140
140
140
140
Operating Voltage Range
VCC
V
75
75
50
50
Supply Current
ICC
µA
V
ASM707E/708E
ASM705/707/813L, Note 1
ASM706/708 Note 1
4.50
4.25
4.65
4.40
4.75
4.50
RESET Threshold
VRT
RESET Threshold
Hysteresis
RESET Pulse Width
Note 1
Note 1
40
mV
ms
µs
µs
V
tRS
tMR
140
200
280
0.15
MR Pulse Width
MR to RESET Out Delay
tMD
VIH
VIL
Note 1
0.25
2.0
MR Input Threshold
MR Pullup current
0.8
600
MR = 0V
100
250
µA
ISOURCE = 800µA
ISINK = 3.2mA
ASM705/6/7/8, VCC = 1.2V,
ISINK = 100µA
ASM707/8/813L, ISOURCE =
800µA
ASM707/8, ISINK = 1.2mA
ASM813L, ISINK =3.2mA
ASM813L, VCC = 1.2V,
ISOURCE = 4µA
VCC - 1.5
RESET Output Voltage
RESET Output Voltage
0.4
0.3
V
V
VCC - 1.5
0.4
0.4
0.9
Watchdog Timeout
Period
WDI Pulse Width
tWD
ASM705/6/813L
1.00
1.60
2.25
S
ns
V
tWP
VIH
VIL
VIL = 0.4V, VIH=0.8VCC,
ASM705/706/813L, VCC = 5V
50
3.5
WDI Input Threshold
0.8
ASM705/6/813L, WDI = VCC
ASM705/6/813L, WDI = 0V
ASM705/6/813L, ISOURCE =
800µA
ASM705/6/813L, ISINK =
1.2mA
50
-50
150
WDI Input Current
µA
V
-150
VCC - 1.5
VOH
VOL
WDO Output Voltage
0.4
PFI Input Threshold
PFI Input Current
VCC = 5V
1.2
-25
1.25
0.01
1.3
25
V
nA
VOH
VOL
ISOURCE = 800µA
ISINK = 3.2mA
VCC - 1.5
V
PFO Output Voltage
0.4
Notes 1: RESET (ASM705/6/7/8), RESET(ASM707/8, ASM813L)
Low Power µP Supervisor Circuits
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Notice: The information in this document is subject to change without notice.
ASM705/706/707/708
ASM813L
April 2008
rev 1.6
Package Dimensions
8-Pin MicroSO
Low Power µP Supervisor Circuits
9 of 15
Notice: The information in this document is subject to change without notice.
ASM705/706/707/708
ASM813L
April 2008
rev 1.6
Package Dimensions (contd)
Plastic DIP (8-Pin)
Low Power µP Supervisor Circuits
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Notice: The information in this document is subject to change without notice.
ASM705/706/707/708
ASM813L
April 2008
rev 1.6
Package Dimensions (contd)
SO (8-Pin)
Low Power µP Supervisor Circuits
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Notice: The information in this document is subject to change without notice.
ASM705/706/707/708
ASM813L
April 2008
rev 1.6
Ordering Codes
Package
Pins-Package
Reset Threshold
Temperature
Part Number
Marking
TIN - LEAD DEVICES
ASM705 Active LOW Reset, Watchdog Output And Manual RESET
ASM705CPA
ASM705CSA
ASM705CUA
ASM705EPA
ASM705ESA
ASM705EUA
4.65
4.65
4.65
4.65
4.65
4.65
0°C to +70 °C
0°C to +70 °C
0°C to +70 °C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
8-Plastic DIP
8-SO
ASM705CPA
ASM705CSA
ASM705CUA
ASM705EPA
ASM705ESA
ASM705EUA
8-MicroSO
8-Plastic DIP
8-SO
8-MicroSO
ASM706 Active LOW Reset, Watchdog Output And Manual RESET
ASM706CPA
ASM706CSA
ASM706CUA
ASM706EPA
ASM706ESA
4.40
4.40
4.40
4.40
4.40
0°C to +70 °C
0°C to +70 °C
0°C to +70 °C
-40°C to +85°C
-40°C to +85°C
8-Plastic DIP
8-SO
ASM706CPA
ASM706CSA
ASM706CUA
ASM706EPA
ASM706ESA
8-MicroSO
8-Plastic DIP
8-SO
ASM707 Active LOW & HIGH Reset with Manual RESET
ASM707CPA
ASM707CSA
ASM707CUA
ASM707EPA
ASM707ESA
4.65
4.65
4.65
4.65
4.65
0°C to +70 °C
0°C to +70 °C
0°C to +70 °C
-40°C to +85°C
-40°C to +85°C
8-Plastic DIP
8-SO
ASM707CPA
ASM707CSA
ASM707CUA
ASM707EPA
ASM707ESA
8-MicroSO
8-Plastic DIP
8-SO
ASM708Active LOW & HIGH Reset with Manual RESET
ASM708CPA
ASM708CSA
ASM708CUA
ASM708EPA
ASM708ESA
4.40
4.40
4.40
4.40
4.40
0°C to +70 °C
0°C to +70 °C
0°C to +70 °C
-40°C to +85°C
-40°C to +85°C
8-Plastic DIP
8-SO
ASM708CPA
ASM708CSA
ASM708CUA
ASM708EPA
ASM708ESA
8-MicroSO
8-Plastic DIP
8-SO
ASM813L Active HIGH Reset, Watchdog Output And Manual RESET
ASM813LCPA
ASM813LCSA
ASM813LCUA
ASM813LEPA
ASM813LESA
4.65
4.65
4.65
4.65
4.65
0°C to +70 °C
0°C to +70 °C
0°C to +70 °C
-40°C to +85°C
-40°C to +85°C
8-Plastic DIP
8-SO
ASM813LCPA
ASM813LCSA
ASM813LCUA
ASM813LEPA
ASM813LESA
8-MicroSO
8-Plastic DIP
8-SO
Low Power µP Supervisor Circuits
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Notice: The information in this document is subject to change without notice.
ASM705/706/707/708
ASM813L
April 2008
rev 1.6
Ordering Codes
Package
Pins-Package
Reset Threshold
Temperature
Part Number
Marking
LEAD FREE DEVICES
ASM705 Active LOW Reset, Watchdog Output And Manual RESET
ASM705CPAF
ASM705CSAF
ASM705CUAF
ASM705EPAF
ASM705ESAF
ASM705EUAF
4.65
4.65
4.65
4.65
4.65
4.65
0°C to +70 °C
0°C to +70 °C
0°C to +70 °C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
8-Plastic DIP
8-SO
ASM705CPAF
ASM705CSAF
ASM705CUAF
ASM705EPAF
ASM705ESAF
ASM705EUAF
8-MicroSO
8-Plastic DIP
8-SO
8-MicroSO
ASM706 Active LOW Reset, Watchdog Output And Manual RESET
ASM706CPAF
ASM706CSAF
ASM706CUAF
ASM706EPAF
ASM706ESAF
4.40
4.40
4.40
4.40
4.40
0°C to +70 °C
0°C to +70 °C
0°C to +70 °C
-40°C to +85°C
-40°C to +85°C
8-Plastic DIP
8-SO
ASM706CPAF
ASM706CSAF
ASM706CUAF
ASM706EPAF
ASM706ESAF
8-MicroSO
8-Plastic DIP
8-SO
ASM707 Active LOW & HIGH Reset with Manual RESET
ASM707CPAF
ASM707CSAF
ASM707CUAF
ASM707EPAF
ASM707ESAF
4.65
4.65
4.65
4.65
4.65
0°C to +70 °C
0°C to +70 °C
0°C to +70 °C
-40°C to +85°C
-40°C to +85°C
8-Plastic DIP
8-SO
ASM707CPAF
ASM707CSAF
ASM707CUAF
ASM707EPAF
ASM707ESAF
8-MicroSO
8-Plastic DIP
8-SO
ASM708Active LOW & HIGH Reset with Manual RESET
ASM708CPAF
ASM708CSAF
ASM708CUAF
ASM708EPAF
ASM708ESAF
4.40
4.40
4.40
4.40
4.40
0°C to +70 °C
0°C to +70 °C
0°C to +70 °C
-40°C to +85°C
-40°C to +85°C
8-Plastic DIP
8-SO
ASM708CPAF
ASM708CSAF
ASM708CUAF
ASM708EPAF
ASM708ESAF
8-MicroSO
8-Plastic DIP
8-SO
ASM813L Active HIGH Reset, Watchdog Output And Manual RESET
ASM813LCPAF
ASM813LCSAF
ASM813LCUAF
ASM813LEPAF
ASM813LESAF
4.65
4.65
4.65
4.65
4.65
0°C to +70 °C
0°C to +70 °C
0°C to +70 °C
-40°C to +85°C
-40°C to +85°C
8-Plastic DIP
8-SO
ASM813LCPAF
ASM813LCSAF
ASM813LCUAF
ASM813LEPAF
ASM813LESAF
8-MicroSO
8-Plastic DIP
8-SO
Note:
For parts to be packed in Tape and Reel, add “-T” at the end of the part number.
Low Power µP Supervisor Circuits
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Notice: The information in this document is subject to change without notice.
ASM705/706/707/708
ASM813L
April 2008
rev 1.6
Feature Summary
ASM705
ASM706
ASM707
ASM708
ASM813L
Power fail detector
♦
♦
♦
♦
♦
♦
♦
♦
♦
♦
♦
♦
Brownout detection
Manual RESET input
Power-up/down RESET
Watchdog Timer
♦
♦
♦
♦
♦
♦
♦
♦
♦
♦
♦
♦
Active HIGH RESET output
Active LOW RESET output
RESET Threshold (V)
♦
♦
♦
♦
♦
♦
4.65
4.40
4.65
4.40
4.65
Low Power µP Supervisor Circuits
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Notice: The information in this document is subject to change without notice.
ASM705/706/707/708
ASM813L
April 2008
rev 1.6
PulseCore Semiconductor Corporation
1715 S. Bascom Ave Suite 200
Campbell, CA 95008
Tel: 408-879-9077
Fax: 408-879-9018
Copyright © PulseCore Semiconductor
All Rights Reserved
Part Number: ASM705 / 706 / 707 / 708
ASM813L
Document Version: 1.6
www.pulsecoresemi.com
© Copyright 2006 PulseCore Semiconductor Corporation. All rights reserved. Our logo and name are trademarks or registered trademarks
of PulseCore Semiconductor. All other brand and product names may be the trademarks of their respective companies. PulseCore reserves
the right to make changes to this document and its products at any time without notice. PulseCore assumes no responsibility for any errors
that may appear in this document. The data contained herein represents PulseCore’s best data and/or estimates at the time of issuance.
PulseCore reserves the right to change or correct this data at any time, without notice. If the product described herein is under development,
significant changes to these specifications are possible. The information in this product data sheet is intended to be general descriptive
information for potential customers and users, and is not intended to operate as, or provide, any guarantee or warrantee to any user or
customer. PulseCore does not assume any responsibility or liability arising out of the application or use of any product described herein, and
disclaims any express or implied warranties related to the sale and/or use of PulseCore products including liability or warranties related to
fitness for a particular purpose, merchantability, or infringement of any intellectual property rights, except as express agreed to in
PulseCore’s Terms and Conditions of Sale (which are available from PulseCore). All sales of PulseCore products are made exclusively
according to PulseCore’s Terms and Conditions of Sale. The purchase of products from PulseCore does not convey a license under any
patent rights, copyrights; mask works rights, trademarks, or any other intellectual property rights of PulseCore or third parties. PulseCore
does not authorize its products for use as critical components in life-supporting systems where a malfunction or failure may reasonably be
expected to result in significant injury to the user, and the inclusion of PulseCore products in such life-supporting systems implies that the
manufacturer assumes all risk of such use and agrees to indemnify PulseCore against all claims arising from such use.
Low Power µP Supervisor Circuits
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Notice: The information in this document is subject to change without notice.
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