R5105N Series
Compact Watchdog Timer with VD
No.EK-159-091101 CMOS Microprocessor Supervisory
The R5105N Series are CMOS-b ased s ystem pow er 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 (ISS)························Typ. 11μA (VDD=-VDET+0.5V,
Clock pulse input)
Operating Voltage Range (VDD)······0.9V to 6.0V
(VD Section)
Detector Th res hol d Range (-V
DET
)
···1.5V to 5.5V (internally fixed)
Detector Threshold Accuracy
··········± 1%
Temp. coeff. of Detector Threshold
···Typ. ± 100ppm/°C
Output Delay Time (tPLH)·················Typ. 370ms (CD=0.1μF)
Output Delay Time Accuracy··········± 16% (-40°C
<
=
Topt
<
=
105°C)
(WDT Section)
Watchdog Timeout Period (tWD)······ Typ. 310ms (CTW=0.1μF)
Reset Hold Time of WDT (tWR) ······· Typ. 34ms (CTW=0.1μF)
W atchdog Timeout Period Accuracy
····± 33% (-40°C
<
=
Topt
<
=
105°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
TYPICAL APPLICATION
R5105Nxx1A
(Nch. open drain output)
VDD
GND
SCK
RESETB
CD
CTW
WATCHDOG
TIMER CLOCK
DETECTOR
3
6
2
4
5
1
Vref2 Vref1
R5105Nxx1C
(CMOS output)
VDD
GND
SCK
RESETB
CD
CTW
3
6
2
4
5
1
WATCHDOG
TIMER CLOCK
DETECTOR
Vre
f
2Vref1
CD
VDD
RESET
I/O
R
CTW
GND
VDD
CD
RESETB
SCK
CTW
3
6 5 2
4
1
Microprocessor
R5105Nxx1A
Series
Power Sup ply
SELECTION GUIDE
Package Quantity per Reel Part No.
SOT-23-6 3,000 pcs R5105N
.
xx
.
1
.
-TR-F
.
xx
.
: S pecify 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) TIMING CHART
SOT-23-6
6 5 4
1 2 3
1 SCK Watchdog timer clock input pin
2 CTW Ext. Cap. pin for setting reset and
watchdog timeout period of WDT
3 VDD Power supply pin
4 RESETB Output pin for Reset "L" signal
5 GND Ground pin
6 CD Ext. Cap. pin for setting output
delay time of VD
APPLICATION
Monitoring of the power system of devices equipped with microprocessors
-VDET
+VDET
V
RESETB
tWR
V
CTW
V
SCK
V
DD
Vref2H
Vref2L
tPLH
V
CD
tPHL tPHL
tPLH
tWDItWD
-VTCD
+VTCD
tPHL : Output delay time
tWDI : tWD/10 (SCK pulses input during this period are ignored.)
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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
http://www.ricoh.com/LSI/
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.
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.