Microprocessor Supervisory Circuit
R5108G SERIES
NO. EA-171-070711
OUTLINE
The R5108G Series are CMOS-based µ con supervisory circuit, or high accuracy and ultra low supply current
voltage detector with built-in delay and watchdog timer. When the SENSE voltage is down across the threshold,
or the watchdog timer does not detect the system clock from the µ con, the reset output is generated. The
voltage detector circuit is used for the system reset, etc. The detector threshold is fixed internally, and the
tolerance is ±1.0%. The released delay time (Power-on Reset Delay) circuit is built-in, and output delay time is
adjustable with an external capacitor. When the sense voltage becomes the released voltage, the reset state will
be maintained during the delay time. The time out period of the watchdog timer can be also set with an external
capacitor. The output type of the reset is selectable, Nch open-drain, or CMOS. There is a function to stop
supervising clock by the watchdog timer (INH function). A necessary voltage source can be supervised with
SENSE pin. The package is small SSOP-8G.
FEATURES
• Built-in a watchdog timer's time out period accuracy
±30%
• Timeout period for watchdog and generating a reset signal can be set by an external capacitor
• Detector Threshold Voltage ····························· 0.1V stepwise setting in the range from 1.5V to 5.5V
• Supply current ·················································· Typ. 11µA
• Operating Voltage ············································ 1.5V to 6.0V
• High Accuracy Output Voltage of Detector Threshold ············································· ±1.0%
• Power-on Reset Delay Time accuracy············· ±20%
• Power-on reset delay time of the voltage detector can be set with an external capacitor.
• Small Package ················································· SSOP-8G (0.65mm pitch)
APPLICATION
• Supervisory circuit for equipment with using microprocessors.
1
R5108G
BLOCK DIAGRAMS
SENSE
VDD
+
CD
-
+
GND
WATCHDOG
TIMER
TW
CLOCK
DETECTOR
SCK
RESETB
INH
R5108GxxxA
SENSE
VDD
+
CD
-
+
GND
TW
WATCHDOG
TIMER
CLOCK
DETECTOR
SCK
RESETB
INH
R5108GxxxC
2
R5108G
SELECTION GUIDE
The selection can be made with designating the part number as shown below:
←part Number
R5108Gxx1x-TR
↑ ↑↑ ↑
a bcd
Code
Descriptions
Designation of Package Type;
G: SSOP8G (2.9mmx4.0mm)
Designation of Detector Threshold Voltage (-VDET)
0.1V stepwise setting is possible in the range from 1.5V to 5.5V
Designation of the output type of RESETB
A: Nch Open-drain
C: CMOS Output
a
b
c
d
Designation of Taping Type
PIN CONFIGURATION
RESETB
1
SENSE
2
CD
3
R5108GxxxA
R5108GxxxC
8
VDD
7
TW
6
INH
SCK
GND
SSOP8G (0.65mm pitch)
PIN DESCRIPTION
Pin No
Symbol
Pin Description
1
RESETB
2
SENSE
3
CD
4
GND
Ground Pin
5
SCK
Clock Input Pin from Microprocessor
6
INH
Inhibit Pin ("L": Inhibit the watchdog timer)
7
TW
External Capacitor Pin for Setting Reset and Watchdog Timeout
Periods
8
VDD
Power supply Pin
Output Pin for Reset signal of Watchdog timer and Voltage
Detector. (Output “L” at detecting Detector Threshold and
Watchdog Timer Reset.)
Voltage Detector Voltage Sense Pin
External Capacitor Pin for Setting Delay Time of Voltage Detector
3
R5108G
ABSOLUTE MAXIMUM RATINGS
Topt=25°C, VSS=0V
Symbol
VIN
Item
Rating
Unit
-0.3∼7.0
V
Voltage of CD Pin
-0.3∼VIN+0.3
V
Voltage of TW Pin
-0.3∼VIN+0.3
V
Voltage of RESETB Pin
-0.3∼7.0
V
Voltage of SCK Pin
-0.3∼7.0
V
Voltage of INH Pin
-0.3∼7.0
V
Voltage of SENSE Pin
-0.3∼7.0
V
20
mA
300
mW
Supply Voltage
VCD
Output Voltage
VTW
VRESETB
VSCK
Input Voltage
VINH
VSENSE
IRESETB
Output Current
PD
Current of RESETB Pin
Power Dissipation
Topt
Operating Temperature Range
-40∼+105
°C
Tstg
Storage Temperature Range
-55∼+125
°C
ELECTRICAL CHARACTERISTICS
R5108GxxxA/C
Unless otherwise specified, VIN=6.0V, CTW =0.1uF, CD=0.1uF, Rpull-up=100kΩ,Topt=25°C
The number of Bold font applied to the temperature range from -40°C to 105°C
Symbol
VIN
Iss
Supply Current
Detector Threshold
∆-VDET/
∆Topt
tpLH
Detector Threshold
Temperature Coefficient
Detector Threshold
Hysteresis
Output Delay Time
VINL
Minimum Operating Voltage
IDOUTN
IDOUTP
Conditions
Output Current (RESETB
Output pin)
Output Current (RESETB
Output pin)
Min.
Typ.
1.5
Operating Voltage
-VDET
VHYS
4
Item
VIN=(-VDET)+0.5V
Clock Pulse Input
Voltage Detector
SENSE pin Threshold
11
x0.990
x0.972
Nch, VDD=6.0V,
VDS=0.5V(R5108GxxxC)
Watchdog Timer
6.0
V
15
µA
x1.010
x1.015
V
ppm/
°C
(-VDET) (-VDET) (-VDET)x
x0.03
0.07
x0.05
340
467
370
ms
0.6
V
RESETB≤0.1V,
pull-up=100kΩ
Nch, VDD=1.2V, VDS=0.1V
Unit
±100
-40°C≤Topt≤105°C
CD=0.1µF
Max.
0.9
V
0.38
0.80
mA
0.65
0.90
mA
TWD
Watchdog Timeout period
CTW =0.1uF
230
310
450
ms
TWR
Reset Hold Time of WDT
CTW =0.1uF
29
34
48
ms
6.0
V
VSCKH
SCK Input "H"
VSCKL
SCK Input "L"
VINHH
INH Input "H"
VINx0.8
0.0
1.0
VINx0.2
6.0
V
V
R5108G
Symbol
Item
Conditions
Min.
Typ.
0.00
VINHL
INH Input "L"
RINH
INH pull-up Resistance
TSCKW
SCK Input Pulse Width
60
VSCKL=VINx0.2,
VSCKH=VINx0.8
500
110
Max.
Unit
0.35
V
164
kΩ
ns
*Bold Type is guaranteed by design.
TYPICAL APPLICATIONS
Power supply
R
VDD
RESET
RESETB
µP
SENSE
R5108GxxxA SCK
INH
C
Series
D
I/O
TW
GND
CCD
SW
VDD
CTW
VDD
Power supply
VDD
RESETB
RESET
SENSE
R5108GxxxC
INH
Series
CD
SW
GND
µP
I/O
SCK
TW
CCD
CTW
TEST CIRCUIT
R(R5108GxxxA)
A
RESETB
VDD
R5108GxxxA/C
SENSE
INH
C
CD
SCK
Series
GND
Clock Input
TW
C
TW
CD
Supply Current Test Circuit
5
R5108G
TIMING DIAGRAM (R5108GxxxA/R5108GxxxC)
(Nch open-drain, RESETB pin is pulled up to VDD.)
VDD
ＩNＨ
SENSE
+VDET
-VDET
CD
tpLH
VTCD
TWDI
TWD
VrefH
TW
VrefL
tpHL
TWR
SCK
tpLH
RESETB
(1)
6
(2)
(4)
(3)
(5)
(6)
R5108G
OPERATION
When the SENSE pin voltage becomes more than the released voltage (+VDET), after the released delay
time (or the power on reset time tpLH), the output of RESETB becomes “H” level.
When the SCK pulse is input, the watchdog timer is cleared, and TW pin mode changes from discharge
mode to charge mode. When the TW pin voltage becomes higher than VREFH, the mode will change into
discharge, and next watchdog time count starts.
Unless the SCK pulse is input, WDT will not be cleared, and during the charging period of TW pin,
RESETB="L".
When the SENSE pin becomes lower than the detector threshold voltage, RESETB outputs "L".
If "L" signal is input to the INH pin, the RESETB outputs "H", regardless the SCK clock state.
When the signal to the INH pin is set from "L" to "H", the watchdog starts supervising the system clock.
∗ Watchdog Timeout period/Reset hold time
The watchdog timeout period and reset hold time can be set with an external capacitor to TW pin.
The next equations describe the relation between the watchdog timeout period and the external capacitor
value, or the reset hold time and the external capacitor value.
tWD(s) = 3.1*10 × C (F)
6
tWR(s)=tWD/9
The watchdog timer (WDT) timeout period is determined with the discharge time of the external capacitor.
During the watchdog timeout period, if the clock pulse from the system is detected, WDT is cleared and the
capacitor is charged. When the charge of the capacitor completes, another watchdog timeout period starts
again. During the watchdog timeout period, if the clock pulse from the system is not detected, during the
next reset hold time RESETB pin outputs "L".
After starting the watchdog timeout period, (just after from the discharge of the external capacitor) even if the clock pulse
is input during the time period "TWDI", the clock pulse is ignored.
TWDI[s]=TWD/10
Released Delay Time (Power-on Reset delay time)
The released delay time can be set with an external capacitor connected to the CD pin. The next equation describes the
relation between the capacitance value and the released delay time (tpLH).
tpLH(s)=3.7×106× C(F)
Note that the temperature dependence graph in the typical characteristics does not contain the temperature characteristics
of the external capacitor.
Minimum Operating Voltage (VINL)
We specified the minimum operating voltage as the minimum input voltage in which the condition of RESETB pin being
0.1V or lower than 0.1V. (Herein, pull-up resistance is set as 100kΩ in the case of the Nch open-drain output type.
Inhibit (INH) Function
If INH pin is set at "L", the watchdog timer stops monitoring the clock, and the RESETB output will be dominant by the
voltage detector's operation. Therefore, if the SENSE pin voltage is set at more than the detector threshold level, RESETB
outputs "H" regardless the clock pulse. INH pin is pulled up with a resistor (TYP. 110kΩ) internally.
7
R5108G
SENSE Function
Built-in Voltage detector monitors the input voltage for SENSE pin. To obtain the normal detector threshold, Vin≥1.5V
must be secured.
RESETB Output
RESETB pin's output type is selectable either the Nch open-drain output or CMOS output. If the Nch
open-drain type output is selected, the RESETB pin is pulled up with an external resistor to an appropriate
voltage source.
Clock Pulse Input
Built-in watchdog timer is cleared with the SCK clock pulse within the watchdog timeout period.
Power on Reset Operation against the input gtlitch
VDD
(tpLH1 < tpLH)
+V DET
-V DET
0V
Perfect Discharge
CD
+VTCD
-V TCD
0V
Imperfect Discharge
RESETB
0V
tpLH
tpLH1
APPLICATION NOTES
If a resistor is connected to the VDD pin, the operation might be unstable with the supply current of IC itself.
VDD
VDD
R1
VDD
R1
VIN
R2
R5108
R1
VIN
VIN
R5108
R5108
RESETB
CMOS
RESETB
Output
Connection examples affected by the conduction current
8
R2
RESETB
R5108G
TYPICAL CHARACTERISTICS
1)
Supply Current vs. Input Voltage
105℃
25℃
-50℃
0
2)
R510xN301A/C, R510xG301A/A
CURRENT Iss [uA]
CURRENT Iss [uA]
R510xN151A/C, R510xG151A/C
20
18
16
14
12
10
8
6
4
2
0
1
2
3
4
SUPPLY VOLTAGE [V]
5
6
20
18
16
14
12
10
8
6
4
2
0
105℃
25℃
-50℃
0
2
3
4
SUPPLY VOLTAGE [V]
5
6
Detector Threshold vs. Temperature
R510xN151A/C, R510xG151A/C
R510xN271A/C, R510xG271A/C
2.740
1.530
1.520
DETECT VOLTAGE [V]
DETECT VOLTAGE [V]
1
1.510
1.500
1.490
1.480
1.470
-50
-25
0
25
50
75
TEMPERATURE [℃]
100
125
2.730
2.720
2.710
2.700
2.690
2.680
2.670
2.660
-50
-25
0
25
50
75
TEMPERATURE [℃]
100
125
R510xN421A/C R510xG421A/C
DETECT VOLTAGE [V]
4.280
4.260
4.240
4.220
4.200
4.180
4.160
4.140
4.120
-50
-25
0
25
50
75
TEMPERATURE [℃]
100
125
9
R5108G
3)
Detector Threshold Hysteresis vs. Temperature
R510xN271A/C R510xG271A/C
7.0
6.0
6.0
HYSTERESIS [%]
HYSTERESIS [%]
R510xN151A/C R510xG151A/C
7.0
5.0
4.0
3.0
-50
-25
0
25
50
75
TEMPERATURE [℃]
100
125
R510xN421A/C R510xG421A/C
HYSTERESIS [%]
7.000
6.000
5.000
4.000
3.000
-50
-25
0
25
50
75
TEMPERATURE [℃]
100
125
4) Detector Threshold vs. Input Voltage
R5108G151A/C
1.53
Topt=25℃
DETECT VOLTAGE [V]
1.52
1.51
1.5
1.49
1.48
1.47
1.5
10
2.0
2.5 3.0 3.5 4.0 4.5 5.0
SUPPLY VOLTAGE VDD [V]
5.5
6.0
5.0
4.0
3.0
-50
-25
0
25
50
75
TEMPERATURE [℃]
100
125
R5108G
5)
Nch Driver Output Current vs. VDS Topt=25°C
R510xN, R510xG
20
VDD=6.0V
OUTPUT CURRENT [mA]
18
16
VDD=4.0V
VDD=5.0V
14
VDD=3.0V
12
VDD=2.0V
10
8
VDD=1.5V
6
4
VDD=1.0V
2
0
0.0
6)
0.2
0.4
0.6
0.8
VDS [V]
1.0
1.2
1.4
Nch Driver Output Current vs. VDD
R510xN, R510xG
20
18
18
14
OUTPUT CURRENT [mA]
Vds=0.3V
16
OUTPUT CURRENT [mA]
R510xN, R510xG
20
Topt=-40℃
12
25℃
10
8
105℃
6
16
Vds=0.5V
25℃
Topt=-40℃
14
12
10
4
8
105℃
6
4
2
2
0
0
0
0
1
2
3
4
SUPPLY VOLTAGE VDD [V]
5
1
6
2
3
4
5
SUPPLY VOLTAGE VDD [V]
6
7) Pch Driver Output Current vs. VDD
R510xN, R510xG
2.0
1.8
VDS=0.3V
1.6
OUTPUT CURRENT [mA]
OUTPUT CURRENT [mA]
1.8
1.4
1.2
1.0
-40℃
0.8
R510xN, R510xG
2.0
0.6
25℃
0.4
105℃
0.2
VDS=0.5V
1.6
1.4
1.2
-40℃
1.0
25℃
0.8
0.6
105℃
0.4
0.2
0.0
0.0
0
1
2
3
4
SUPPLY VOLTAGE [V]
5
6
0
1
2
3
4
SUPPLY VOLTAGE [V]
5
6
11
R5108G
R510xN, R510xG
2.0
OUTPUT CURRENT [mA]
1.8
VDS=1.0V
-40℃
1.6
25℃
1.4
1.2
105℃
1.0
0.8
0.6
0.4
0.2
0.0
0
1
2
3
4
SUPPLY VOLTAGE [V]
5
6
9)
Released Delay Time vs. Temperature
R510xN, R510xG
R510xN, R510xG
500
480
460
440
420
400
380
360
340
320
300
POWER ON RESET DELAY
tpLH[ms]
POWER ON RESET DELAY
tpLH [ms]
8) Released Delay Time vs. Input Voltage
Topt=25℃
0
1
2
3
4
5
SUPPLY VOLTAGE [V]
6
500
480
460
440
420
400
380
360
340
320
300
-50 -25
7
10) Detector Output Delay Time vs. Temperature
VDD=6V
0
25 50 75 100 125 150
TEMPERATURE [℃]
11) WDT Reset Timer vs. Temperature
R510xN, R510xG
R510xN, R510xG
100
50
90
RESET TIME [msec]
46
70
TIME [usec]
48
1us
80
(-VDET)+1
60
INPUT
(-VDET)-1
50
40
30
20
10
0
-50
12
44
42
40
38
36
34
32
-25
0
25
50
75
TEMPERATURE [℃]
100
125
30
-50
-25
0
25
50
75
TEMPERATURE [℃]
100
125
R5108G
12) WDT Timeout Period vs. Temperature
R510xN, R510xG
R510xN, R510xG
400
50
380
48
360
46
RESET TIME [msec]
Timeout
Period [msec]
13) WDT Reset Timer vs. Input Voltage
340
320
300
280
260
44
42
40
38
36
240
34
220
32
200
30
-50
-25
0
25
50
75
TEMPERATURE [℃]
100
125
1
2
3
4
SUPPLY VOLTAGE [V]
5
6
14) WDT Timeout Period vs. Input Voltage
R510xN, R510xG
400
Timeout Period [msec]
380
360
340
320
300
280
260
240
220
200
1
2
3
4
SUPPLY VOLTAGE [V]
5
6
13