R5105N Series
Compact Watchdog Timer with VD
The R5105N Series are CMOS-based system power ICs with a voltage detector (VD) and watchdog timer (WDT) integrated in a single
chip. R5105N monitors the power system of devices equipped with microprocessors and prevents system runaway with a reset
signal when a malfunction occurs. The output delay time of the VD and watchdog timeout period/reset time can be adjusted high
accuracy with an external capacitor.
FEATURES
•
Supply Current (I
SS
) ························Typ. 11μA (V
DD
=-V
DET
+0.5V,
•
Operating Voltage Range (V
DD
) ······0.9V to 6.0V
Clock pulse input)
•
Output Delay Time (t
PLH
)················· Typ. 370ms (C
D
=0.1μF)
•
Output Delay Time Accuracy··········
±
16% (-40°C
<
Topt
<
105°C)
=
=
(WDT Section)
•
Watchdog Timeout Period (t
WD
)······ Typ. 310ms (C
TW
=0.1μF)
(VD Section)
•
Detector Threshold Range (-V
DET
) ···1.5V to 5.5V (internally fixed)
•
Reset Hold Time of WDT (t
WR
) ······· Typ. 34ms (C
TW
=0.1μF)
•
Detector Threshold Accuracy ··········± 1%
•
Watchdog Timeout Period Accuracy ····
±
33% (-40°C
<
Topt
<
105°C)
=
=
•
Temp. coeff. of Detector Threshold ···Typ.
±
100ppm/°C
•
Package ········································· SOT-23-6
(The above shows specification at Topt=25
°
C. Design assurance value at -40
°
C
<
Topt
<
105
°
C is also available. For details, please refer to the datasheet.)
=
=
BLOCK DIAGRAMS
R5105Nxx1A
(Nch. open drain output)
V
DD
3
C
D
6
V
DD
3
C
D
6
TYPICAL APPLICATION
R5105Nxx1C
(CMOS output)
Power Supply
Microprocessor
V
DD
R
Vref2
Vref1
Vref2
3
V
DD
Vref1
RESETB
4
R5105Nxx1A
Series
SCK
RESET
I/O
C
TW
2
WATCHDOG
TIMER
CLOCK
DETECTOR
5 GND
1 SCK
C
TW
2
WATCHDOG
TIMER
CLOCK
DETECTOR
5 GND
1 SCK
C
D
1
2
6
C
D
GND
C
TW
RESETB 4
RESETB 4
5
C
TW
SELECTION GUIDE
Package
SOT-23-6
Quantity per Reel
3,000 pcs
Part No.
R5105N.xx.1.
∗
-TR-F
.xx.
: Specify the detector threshold within the range 1.5V (.15.) to 5.5V (.55.)
in 0.1V steps.
: Select the output type from (.A.) Nch. open drain or (.C.) CMOS.
.∗
PACKAGE (Top View)
SOT-23-6
6
5
4
TIMING CHART
V
DD
+V
DET
-V
DET
t
PHL
t
PHL
V
CD
+V
TCD
1
2
3
-V
TCD
t
WD
t
WDI
1
2
3
4
5
6
SCK
C
TW
V
DD
RESETB
GND
C
D
Watchdog timer clock input pin
Ext. Cap. pin for setting reset and
watchdog timeout period of WDT
Power supply pin
Output pin for Reset "L" signal
Ground pin
Ext. Cap. pin for setting output
delay time of VD
V
ref2H
V
CTW
V
ref2L
t
PLH
t
PLH
V
SCK
t
WR
V
RESETB
APPLICATION
•
Monitoring of the power system of devices equipped with microprocessors
No.EK-159-091101
∗t
PHL
: Output delay time
∗t
WDI
: t
WD
/10 (SCK pulses input during this period are ignored.)
CMOS Microprocessor Supervisory
1. The products and the product specifications described in this document are subject to change or
discontinuation of production without notice for reasons such as improvement. Therefore, before
deciding to use the products, please refer to Ricoh sales representatives for the latest
information thereon.
2. The materials in this document may not be copied or otherwise reproduced in whole or in part
without prior written consent of Ricoh.
3. Please be sure to take any necessary formalities under relevant laws or regulations before
exporting or otherwise taking out of your country the products or the technical information
described herein.
4. The technical information described in this document shows typical characteristics of and
example application circuits for the products. The release of such information is not to be
construed as a warranty of or a grant of license under Ricoh's or any third party's intellectual
property rights or any other rights.
5. The products listed in this document are intended and designed for use as general electronic
components in standard applications (office equipment, telecommunication equipment,
measuring instruments, consumer electronic products, amusement equipment etc.). Those
customers intending to use a product in an application requiring extreme quality and reliability,
for example, in a highly specific application where the failure or misoperation of the product
could result in human injury or death (aircraft, spacevehicle, nuclear reactor control system,
traffic control system, automotive and transportation equipment, combustion equipment, safety
devices, life support system etc.) should first contact us.
6. We are making our continuous effort to improve the quality and reliability of our products, but
semiconductor products are likely to fail with certain probability. In order to prevent any injury to
persons or damages to property resulting from such failure, customers should be careful enough
to incorporate safety measures in their design, such as redundancy feature, firecontainment
feature and fail-safe feature. We do not assume any liability or responsibility for any loss or
damage arising from misuse or inappropriate use of the products.
7. Anti-radiation design is not implemented in the products described in this document.
8. Please contact Ricoh sales representatives should you have any questions or comments
concerning the products or the technical information.
RICOH COMPANY., LTD.
Electronic Devices Company
■Ricoh
presented with the Japan Management Quality Award for 1999.
Ricoh continually strives to promote customer satisfaction, and shares the achievements
of its management quality improvement program with people and society.
■Ricoh
awarded ISO 14001 certification.
The Ricoh Group was awarded ISO 14001 certification, which is an international standard for
environmental management systems, at both its domestic and overseas production facilities.
Our current aim is to obtain ISO 14001 certification for all of our business offices.
http://www.ricoh.com/LSI/
RICOH COMPANY, LTD.
Electronic Devices Company
● Shin-Yokohama office (International Sales)
3-2-3, Shin-Yokohama, Kohoku-ku, Yokohama City, Kanagawa 222-8530, Japan
Phone: +81-45-477-1697 Fax: +81-45-477-1698
Ricoh completed the organization of the Lead-free production for all of our products.
After Apr. 1, 2006, we will ship out the lead free products only. Thus, all products that
will be shipped from now on comply with RoHS Directive.
RICOH EUROPE (NETHERLANDS) B.V.
● Semiconductor Support Centre
Prof. W.H.Keesomlaan 1, 1183 DL Amstelveen, The Netherlands
P.O.Box 114, 1180 AC Amstelveen
Phone: +31-20-5474-309 Fax: +31-20-5474-791
RICOH ELECTRONIC DEVICES KOREA Co., Ltd.
11 floor, Haesung 1 building, 942, Daechidong, Gangnamgu, Seoul, Korea
Phone: +82-2-2135-5700 Fax: +82-2-2135-5705
RICOH ELECTRONIC DEVICES SHANGHAI Co., Ltd.
Room403, No.2 Building, 690#Bi Bo Road, Pu Dong New district, Shanghai 201203,
People's Republic of China
Phone: +86-21-5027-3200 Fax: +86-21-5027-3299
RICOH COMPANY, LTD.
Electronic Devices Company
● Taipei office
Room109, 10F-1, No.51, Hengyang Rd., Taipei City, Taiwan (R.O.C.)
Phone: +886-2-2313-1621/1622 Fax: +886-2-2313-1623
京公网安备 11010802033920号
EEWORLD
