S-8426A Series
BATTERY BACKUP SWITCHING IC
www.ablicinc.com
© ABLIC Inc., 2006-2015
Rev.2.0_03
The S-8426A Series is a CMOS IC designed for use in the switching circuits of primary and backup power supplies on a
single chip. It consists of two voltage regulators, three voltage detectors, a power supply switch and its controller, as well as
other functions.
In addition to the switching function between the primary and backup power supply, the S-8426A Series can provide the
micro controllers with three types of voltage detection output signals corresponding to the power supply voltage.
Moreover adopting a special sequence for switch control enables the effective use of the backup power supply, making this
IC ideal for configuring a backup system.
Features
Low power consumption
Normal operation:
15 A Max. (VIN = 6 V)
Backup:
4.5 A Max.
Voltage regulator
Output voltage tolerance : 2%
Output voltage:
Independently selectable in 0.1 V steps in the range of 2.3 to 5.4 V
Three built-in voltage detectors (CS, PREEND , RESET )
Detection voltage precision: 2%
Detection voltage:
Selectable in 0.1 V steps in the range of 2.4 to 5.3 V (CS voltage detector)
Selectable in 0.1 V steps in the range of 1.7 to 3.4 V ( PREEND , RESET voltage
detector)
Switching circuit for primary power supply and backup power supply configurable on one chip
Efficient use of backup power supply possible
Special sequence
Backup voltage is not output when the primary power supply voltage does not reach the initial voltage at which the
switch unit operates.
Lead-free, Sn 100%, halogen-free*1
*1. Refer to
Product Name Structure for details.
Applications
Video camera recorders
Still video cameras
Memory cards
SRAM backup equipment
Packages
8-Pin TSSOP
8-Pin SOP(JEDEC)
1
BATTERY BACKUP SWITCHING IC
S-8426A Series
Rev.2.0_03
Block Diagram
VOUT
M1
VIN
VBAT
REG2
PREEND
PREEND
Vsw1
Detector
CS
Voltage
detector
CS
Voltage
detector
RESET
VSW2
Detector
RESET
Voltage
detector
Switch
controller
REG1
VSS
Figure 1
2
VRO
BATTERY BACKUP SWITCHING IC
S-8426A Series
Rev.2.0_03
Product Name Structure
1. Product Name
S-8426A
xx - xxxx
x
Environmental code
U
: Lead-free (Sn 100%), halogen-free
G
: Lead-free (for details, please contact our sales office)
Package name (abbreviation) and IC packing specifications *1
T8T1
: 8-Pin TSSOP, Tape
J8T1
: 8-Pin SOP(JEDEC), Tape
Serial code
*2
Sequentially set from AA to ZZ
*1.
*2.
2.
Refer to the taping specifications.
Refer to the 3. Product Name List.
Package
Package Name
8-Pin TSSOP
8-Pin SOP(JEDEC)
Package
FT008-A-P-SD
FT008-A-P-SD
FJ008-A-P-SD
FJ008-A-P-SD
Environmental code = G
Environmental code = U
Environmental code = G
Environmental code = U
Drawing Code
Tape
FT008-E-C-SD
FT008-E-C-SD
FJ008-D-C-SD
FJ008-D-C-SD
Reel
FT008-E-R-SD
FT008-E-R-S1
FJ008-D-R-SD
FJ008-D-R-S1
3. Product Name List
Table 1
Model No.
S-8426AAA-J8T1x
*1.
Output
Voltage
Output
Voltage
CS
Voltage
5.000
5.000
4.500
CS
Voltage
VOUT
0.95
RESET
RESET
PREEND
PREEND
Voltage
Voltage
Voltage
Voltage
2.900
3.068
2.100
2.207
Switch
Voltage
*1
VDET4
0.77
VDET4 can be calculated by VDET1 with the following equation.
VDET4 = ( VDET1) + 15 {( VDET1) 0.8} 372
Set the CS voltage so that the switch voltage (VSW1) is equal to or greater than the RESET detection
voltage ( VDET2).
Caution
Remark 1.
2.
The selection range is as follows.
VRO, VOUT: 2.3 to 5.4 V (0.1 V steps)
VDET1:
2.4 to 5.3 V (0.1 V steps)
VDET2:
1.7 to 3.4 V (0.1 V steps )
VDET3:
1.7 to 3.4 V (0.1 V steps)
VSW1: VDET1 0.85 or VDET1 0.77
When VSW2 > VDET1, VDET4 0.85 or VDET4
0.77
3.
If a product with a voltage other than above is required, contact our sales representative.
4.
x: G or U
5.
Please select products of environmental code = U for Sn 100%, halogen-free products.
3
BATTERY BACKUP SWITCHING IC
S-8426A Series
Rev.2.0_03
Pin Configurations
8-Pin TSSOP
Top view
Table 2
8
7
6
5
1
2
3
4
Figure 2
Pin No.
1
2
3
4
5
6
7
8
Symbol
VSS
PREEND
VBAT*1
CS
RESET
VOUT*1
*1
VIN
VRO*1
Description
Ground
Output pin of PREEND voltage detector
Backup power supply input pin
Output pin of CS voltage detector
Output pin of RESET voltage detector
Output pin of voltage regulator 2
Primary power supply input pin
Output pin of voltage regulator 1
*1. Mount capacitors between VSS (GND pin) and the VIN, VBAT, VOUT,
and VRO pins. (Refer to the Standard Circuit)
8-Pin SOP(JEDEC)
Top view
Table 3
1
8
2
7
3
6
4
5
Figure 3
Pin No.
1
2
3
4
5
6
7
8
Symbol
VSS
PREEND
VBAT*1
CS
RESET
VOUT*1
VIN*1
VRO*1
Description
Ground
Output pin of PREEND voltage detector
Backup power supply input pin
Output pin of CS voltage detector
Output pin of RESET voltage detector
Output pin of voltage regulator 2
Primary power supply input pin
Output pin of voltage regulator 1
*1. Mount capacitors between VSS (GND pin) and the VIN, VBAT, VOUT,
and VRO pins. (Refer to the Standard Circuit)
4
BATTERY BACKUP SWITCHING IC
S-8426A Series
Rev.2.0_03
Absolute Maximum Ratings
Table 4
(Unless otherwise specified: Ta = 25 C)
Item
Primary power supply input voltage
Backup power supply input voltage
Output voltage of voltage regulator
CS output voltage
RESET output voltage
Symbol
VIN
VBAT
VRO, VOUT
VCS
V RESET
PREEND output voltage
V PREEND
Absolute Maximum Tatings
VSS 0.3 to VSS 18
VSS 0.3 to VSS 18
VSS 0.3 to VIN 0.3
VSS 0.3 to VSS 18
Unit
V
V
V
V
VSS 0.3 to VSS 18
V
VSS 0.3 to VSS 18
V
700*1
850*1
40 to 85
40 to 125
mW
mW
C
C
8-Pin TSSOP
Power dissipation
PD
8-Pin SOP(JEDEC)
Operating ambient temperature
Topr
Storage temperature
Tstg
*1. At mounted on printed circuit board
[Mounted board]
(1) Board size: 114.3 mm × 76.2 mm × t1.6 mm
(2) Board name: JEDEC STANDARD51-7
Caution The absolute maximum ratings are rated values exceeding which the product could suffer physical
damage. These values must therefore not be exceeded under any conditions.
1200
1000
800
8-Pin SOP(JEDEC)
8-Pin TSSOP
600
400
200
0
0
50
100
150
Ambient Temperature (Ta) [ C]
Figure 4
Power Dissipation of Package (Mounted on Printed Circuit Board)
5
BATTERY BACKUP SWITCHING IC
S-8426A Series
Rev.2.0_03
Electrical Characteristics
1. S-8426AAA
Table 5
Item
Output voltage 1
Dropout voltage 1
Load stability 1
Input stability 1
Output voltage temperature
coefficient 1
Output voltage 2
Dropout voltage 2
Load stability 2
Input stability 2
Output voltage temperature
coefficient 2
Primary power input voltage
CS detection voltage
VIN = 6 V, IRO = 30 mA
VIN = 6 V, IRO = 30 mA
VIN = 6 V, IRO = 0.1 to 40 mA
VIN = 6 to 16 V, IRO = 30 mA
VOUT
Vdrop2
VOUT1
VOUT2
VOUT
Ta VOUT
VIN = 6 V, IOUT = 50 mA
VIN = 6 V, IOUT = 50 mA
VIN = 6 V, IOUT = 0.1 to 60 mA
VIN = 6 to 16 V, IOUT = 50 mA
VIN
VDET1
VDET1
RESET detection voltage
VDET2
RESET release voltage
VDET2
PREEND detection voltage
VDET3
Detection voltage
temperature coefficient
Sink current
Leakage current
Conditions
VRO
Vdrop1
VRO1
VRO2
VRO
Ta VRO
CS release voltage
PREEND release voltage
Operating voltage
6
Symbol
(1 / 2)
Ta = 40 to 85 C
Ta = 40 to 85 C
VIN voltage detection
VOUT voltage detection
2.842
2.994
3.068
3.142
V
2
VBAT voltage detection
2.058
2.100
2.142
V
2
2.154
2.207
2.260
V
2
16
V
ppm/
C
ppm/
C
ppm/
C
2
2.30
mA
3
1.50
2.30
mA
3
1.50
2.30
mA
A
3
3
VDET3
Vopr
(Unless otherwise specified: Ta = 25 C)
Test
Min.
Typ.
Max.
Unit
Circuit
4.900 5.000 5.100
V
1
356
474
mV
1
50
100
mV
1
5
20
mV
1
ppm/
100
1
C
4.900 5.000 5.100
V
1
401
540
mV
1
50
100
mV
1
10
30
mV
1
ppm/
100
1
C
16
V
1
4.410 4.500 4.590
V
2
VOUT
VOUT
VOUT
V
2
0.93
0.95
0.97
1.7
VIN or VBAT
VDET1
Ta = 40 to 85 C
Ta VDET1
VDET 2
Ta = 40 to 85 C
Ta VDET 2
VDET 3
Ta = 40 to 85 C
Ta VDET 3
ISINK
ILEAK
VDS = 0.5 V,
VIN = VBAT = 2.0 V
2.900
2.958
100
100
100
RESET
PREEND
CS
VDS = 16 V, VIN = 16 V
1.50
0.1
V
2
2
2
2
BATTERY BACKUP SWITCHING IC
S-8426A Series
Rev.2.0_03
Table 5
Item
Symbol
Switch voltage
VSW1
CS output inhibit voltage
VSW2
VBAT switch
leakage current
ILEAK
VBAT switch resistance
RSW
Switch voltage
temperature coefficient
CS output inhibit voltage
temperature coefficient
Current consumption
(2 / 2)
Conditions
Min.
0.1
30
VSW 1
Ta VSW 1
VSW 2
Ta VSW 2
*1.
1.7
Test
Circuit
V
4
V
5
A
6
7
ppm/
C
4
15
20
3.5
4.5
5.0
ppm/
C
A
A
A
A
A
8
8
8
8
8
4.0
V
7
100
6
7
0.5
1.5
Unit
60
100
ISS1
ISS2
IBAT1
VBAT
Max.
VDET4*1 VDET4*1 VDET4*1
0.75
0.77
0.79
VOUT
VOUT
VOUT
0.93
0.95
0.97
IBAT2
Backup power supply
input voltage
Typ.
5
VDET4 can be calculated by VDET1 with the following equation.
VDET4 = ( VDET1) + 15 {( VDET1) 0.8} 372
Remark The number in the Test Circuit column corresponds to the circuit number in the
Test Circuits section.
7
BATTERY BACKUP SWITCHING IC
S-8426A Series
Rev.2.0_03
Test Circuits
V
VBAT
VIN
VIN
VRO or
VOUT
VSS
10 F
V
V
VSS
100 k
100 k
100 k
VBAT VOUT
VIN
PREEND
VIN
RESET
CS
V
V
V
To measure V DET3, apply 6 V to VIN.
Figure 5 Test Circuit 1
VBAT VOUT CS
VIN
PREEND
VIN
VSS
Figure 6 Test Circuit 2
A
V
A
RESET
A
VIN
VOUT
VIN
VBAT
VBAT
V
VSS
VDS
Measure the value after applying 6 V to VIN.
Figure 7 Test Circuit 3
VIN
Figure 8 Test Circuit 4
Oscillo
scope
VOUT
VIN
VBAT
100 k
F.G.
VIN
Oscillo
scope
VSS VBAT CS
A
VSS
VBAT
Figure 9 Test Circuit 5
VIN
VBAT
VIN
VBAT
Figure 10 Test Circuit 6
VIN
VBAT
VOUT
IOUT
V
VSS
Leave open and measure the value after
applying 6 V to VIN.
Figure 11 Test Circuit 7
8
ISS A
VIN
A IBAT
VSS
VBAT
To measure IBAT2, apply 6 V to VIN and then
leave VIN open and measure IBAT.
Figure 12 Test Circuit 8
BATTERY BACKUP SWITCHING IC
S-8426A Series
Rev.2.0_03
Operation
The internal configuration of the S-8426A Series is as follows.
Voltage regulator 1, which stabilizes input voltage (VIN) and outputs it to VRO
Voltage regulator 2, which stabilizes input voltage (VIN) and outputs it to VOUT
CS voltage detector, which monitors input voltage (VIN)
PREEND voltage detector, which monitors output voltage (VBAT)
RESET voltage detector, which monitors output voltage (VOUT)
Switch unit
The functions and operations of the above-listed elements are described below.
1.
Voltage Regulators
The S-8426A Series features on-chip voltage regulators with a small dropout voltage. The voltage of the VRO and
VOUT pins (the output pins of the voltage regulator) can separately be selected for the output voltage in 0.1 V steps
between the range of 2.3 to 5.4 V.
1. 1 Dropout voltage Vdrop1, Vdrop2
Assume that the voltage output from the VRO pin is VRO(E) under the conditions of output voltage 1 described
in the electrical characteristics table. VIN1 is defined as the input voltage at which output voltage from the VRO
pin becomes 98% of VRO(E) when the input voltage VIN is decreased. Then, the dropout voltage Vdrop1 is
calculated by the following expression.
Vdrop1 = VIN1 VRO(E) 0.98
Similarly, assume that the voltage of the VOUT pin is VOUT(E) under the conditions of output voltage 2 described
in the electrical characteristics table. VIN2 is defined as the input voltage at which the output voltage from the
VOUT pin becomes 98% of VOUT(E). Then, the dropout voltage Vdrop2 is calculated by the following expression.
Vdrop2 = VIN2 VOUT(E) 0.98
2.
Voltage Detector
The S-8426A Series incorporates three high-precision, low power consuming voltage detectors with hysteresis
characteristics. The power of the CS voltage detector is supplied from the VIN and VBAT pins. Therefore, the
output is stable as long as the primary or backup power supplies are within the operating voltage range (1.7 to 16
V). All outputs are Nch open-drain, and need pull-up resistors of about 100 k .
2. 1
CS Voltage Detector
The CS voltage detector monitors the input voltage (VIN) (VIN pin voltage). The detection voltage can be
selected from between 2.4 and 5.3 V in 0.1 V steps. The result of detection is output at the CS pin: Low
for lower voltage than the detection level and High for higher voltage than the release level (however, when
the VOUT pin voltage is the CS output inhibit voltage (VSW2), a low level is output) .
Release voltage
Input voltage
Detection voltage
Output voltage
Figure 13
Definition of Detection and Release Voltages
9
BATTERY BACKUP SWITCHING IC
S-8426A Series
2. 2
Rev.2.0_03
PREEND Voltage Detector
The PREEND voltage detector monitors input voltage (VBAT) (VBAT pin voltage). The detection voltage can
be selected in the range of 1.7 to 3.4 V in 0.1 V step. By using this function, IC notifies if the backup battery is
scarce. The result of detection is output at the PREEND pin: Low for lower voltages than the detection
level and High for higher voltages than the release level.
2. 3
RESET Voltage Detector
The RESET voltage detector monitors output voltage (VOUT) (VOUT pin voltage). The detection voltage can
be selected in the range of 1.7 to 3.4 V in 0.1 V step. The result of detection is output at the RESET pin:
Low for lower voltages than the detection level and High for higher voltages than the release level. RESET
outputs the normal logic if the VOUT pin voltage is 1.0 V or more.
Caution
3.
The PREEND and RESET voltage detectors use the different pins, respectively.
Practically, the current is taken from the VBAT side, and consider the I/O voltage
difference (Vdif) of M1 when M1 is ON.
Switch Unit
The switch unit consists of the VSW1 and VSW2 detectors, a switch controller, voltage regulator 2, and switch
transistor M1 (Refer to Figure 14).
VOUT
VIN
REG2
Switch
controller
M1
VSW1
detector
Figure 14
10
VBAT
VSW2
detector
BATTERY BACKUP SWITCHING IC
S-8426A Series
Rev.2.0_03
3. 1
VSW1 Detector
The VSW1 detector monitors the power supply voltage VIN and sends the results of detection to the switch
controller. The detection voltage (VSW1) can be set to 77 2% or 85 2% of the CS release voltage ( VDET1).
In the products VSW2 > VDET1, the setting value is 77 2% or 85 2% of VDET4 which is calculated with the
following equation.
VDET4 = ( VDET1) + 15 × { ( VDET1) 0.8 } ÷ 372
3. 2
VSW2 Detector
The VSW2 detector monitors the VOUT pin voltage and keeps the CS release voltage output low until the VOUT
pin voltage rises to VSW2 voltage. The CS pin output then changes from low to high if the VIN pin voltage is
more than the CS release voltage ( VDET1) when the VOUT pin voltage rises to 95 2% of the output voltage of
voltage regulator 2 (VOUT). The CS pin output changes from high to low regardless of the VSW2 voltage when
the VIN pin voltage drops to less than the CS detection voltage ( VDET1).
The CS pin output remains high if the VIN pin voltage stays higher than the CS detection voltage ( VDET1)
when the VOUT pin voltage drops to less than the VSW2 voltage due to an undershoot.
3. 3 Switch Controller
The switch controller controls voltage regulator 2 and switch transistor M1. There are two statuses
corresponding to the power supply voltage (VIN) (or power supply voltage (VBAT)) sequence: a special
sequence status and a normal sequence status. When the power supply voltage (VIN) rises and becomes
equal to or exceeds the CS release voltage ( VDET1), the normal sequence status is entered, but until then the
special sequence status is maintained.
(1) Special sequence status
The switch controller sets voltage regulator 2 ON and switch transistor M1 OFF from the initial status until
the primary power supply voltage (VIN) is connected and reaches more than the CS release voltage
( VDET1) in order to prevent consumption of the backup power supply regardless of the VSW1 detector
status. This status is called the special sequence status.
(2) Normal sequence status
The switch controller enters the normal sequence status from the special sequence status once the
primary power supply voltage (VIN) reaches more than the CS release voltage ( VDET1).
Once the normal sequence is entered, the switch controller switches voltage regulator 2 and switch
transistor M1 ON/OFF as shown in Table 6 according to the power supply voltage VIN. The time required
for voltage regulator 2 to be switched from OFF to ON is a few hundred s at most. During this interval,
voltage regulator 2 and switch transistor M1 may both switch OFF and the VOUT pin voltage may drop. To
prevent this, connect a capacitor of 10 F or more to the VOUT pin.
When the VOUT pin voltage becomes lower than the RESET detection voltage, the status returns to the
special sequence status.
IN
Power Supply Voltage (VIN)
Voltage Regulator 2
Switch Transistor M1
VIN > VSW1
ON
OFF
VIN < VSW1
OFF
ON
VOUT Pin Voltage
VOUT
VBAT
Vdif
11
BATTERY BACKUP SWITCHING IC
S-8426A Series
Rev.2.0_03
3. 4 Switch Transistor M1
Voltage regulator 2 is also used to switch from VIN pin to VOUT pin. Therefore, no reverse current flows from
VOUT pin to VIN pin when voltage regulator 2 is OFF. The output voltage of voltage regulator 2 can be
selected from between 2.3 V and 5.4 V in 0.1 V steps.
The on-resistance of switch transistor M1 is 60 or lower (IOUT = 10 to 500 A).
Therefore, when M1 is switched ON and VOUT pin is connected to VBAT pin, the voltage drop (Vdif) caused by
M1 is 60 IOUT (output current) at maximum., and VBAT Vdif (max.) is output to the VOUT pin at minimum.
When voltage regulator 2 is ON and M1 is OFF, the leakage current of M1 is kept below 0.1 A max. (VIN = 6
V, Ta = 25 °C) with the VBAT pin grounded (VSS pin).
VOUT
Vdif
VIN
REG2
M1
Figure 15 Definition of Vdif
12
VBAT
Rev.2.0_03
BATTERY BACKUP SWITCHING IC
S-8426A Series
Timing Chart
V IN (V)
V RO (V)
V OUT (V)
V BAT (V)
V CS (V)
V PREEND (V)
V RESET (V)
Remark CS, PREEND and RESET are pulled up to VOUT. Y-axis is an arbitrary scale.
Figure 16 Operation Timing Chart
13
BATTERY BACKUP SWITCHING IC
S-8426A Series
Rev.2.0_03
Standard Circuit
VRO
10 F
VRO
1k
VBAT
VIN
VOUT
6V
10 F
10 F
S-8426A
Series
VSS
0.1 F
3V
VOUT
RESET
CS
VOUT
100 k
PREEND
VOUT
VOUT
100 k
100 k
Figure 17
Caution 1.
2.
Be sure to add a 10 F or more capacitor to the VOUT and VRO pins.
The above connections and values will not guarantee correct operation. Before setting these
values, perform sufficient evaluation on the application to be actually used.
Precautions
In applications with small IRO or IOUT, the output voltages VRO and VOUT may rise, causing the load stability to exceed
standard levels. Set IRO and IOUT to 10 A or more.
Attach the proper capacitor to the VOUT pin to prevent the RESET voltage detector (which monitors the VOUT pin)
from coming active due to undershoot.
Watch for overshoot and ensure it does not exceed the ratings of the IC chips and/or capacitors attached to the VRO
and VOUT pins.
Add a 10 F or more capacitor to the VOUT and VRO pins.
When VIN rises from the voltage more than VSW1, a low pulse of less than 4 ms flows through the PREEND pin even
when VBAT is more than the PREEND release voltage. Thus when monitoring the PREEND pin, make sure to
take the 4 ms interval or more after the rise of VIN.
Do not apply an electrostatic discharge to this IC that exceeds the performance ratings of the built-in electrostatic
protection circuit.
ABLIC Inc. claims no responsibility for any and all disputes arising out of or in connection with any infringement by
products including this IC of patents owned by a third party.
14
BATTERY BACKUP SWITCHING IC
S-8426A Series
Rev.2.0_03
Application Circuits
1.
When Using Timer Micro controllers for Backup to display PREEND in the primary CPU
10 F
VOUT
VIN
10 F
1k
6V
3V
S-8426A
Series
VBAT
VCC
Timer
microcontroller
RESET
VRO
100 k
CS
CS
PREEND
0.1 F
10 F
100 k
RESET
VSS
100 k
VCC
RESET
Main
CPU
INT
Address data
Figure 18 Application Circuit 1
15
BATTERY BACKUP SWITCHING IC
S-8426A Series
2.
Rev.2.0_03
When Using Secondary Battery as Backup Battery
10 F
10 F
VRO
VOUT
VIN
VCC
S-8426A
Series
100 k
100 k
CS
VBAT
Microcontroller
INT
6V
3V
RESET
RESET
VSS
Figure 19 Application Circuit 2
Remark The backup battery can be floating-recharged by using voltage regulator 1.
3.
Memory Card
Card unit
VIN
VIN
10 F
VOUT
S-8426A
Series
10 F
SRAM
CS
BDT2
PREEND
BDT1
RESET
CS
VBAT
VSS
0.1 F
3V
CS
Figure 20 Application Circuit 3
Caution
16
The above connections and values will not guarantee correct operation. Before setting these values,
perform sufficient evaluation on the application to be actually used.
BATTERY BACKUP SWITCHING IC
S-8426A Series
Rev.2.0_03
Transient Response
1.
Line Transient Response Against Input Voltage Variation
The input voltage variation differs depending on whether the power supply input (0 to 10 V square wave) is applied
or the power supply variation (6 V and 10 V square waves) is applied. This section describes the ringing waveforms
and parameter dependency of each type. The test circuit is shown for reference.
1. 1 Power supply application: 0 to 10 V Square wave
Fast amplifier
Input voltage
0V
10 V
VIN
Overshoot
Undershoot
Oscillo
scope
VOUT
S-8426A
Series
VSS
P.G.
COUT
Output voltage
Figure 21 Power Supply Application:
RL
Figure 22 Test Circuit
0 to 10 V Square Wave
VOUT pin
VRO pin
COUT = 22 F, IOUT = 50 mA, Ta = 25 C
CRO = 22 F, IRO = 30 mA, Ta = 25 C
10 V
10 V
Input Voltage
(5 V/div)
Input Voltage
5 V/div)
0V
Output Voltage
0V
Output Voltage
(0.5 V/div)
(0.5 V/div)
t (100 s/div)
Figure 23 Ringing Waveform of Power Supply
Application (VOUT Pin)
t (100 s/div)
Figure 24 Ringing Waveform of Power Supply
Application (VRO Pin)
17
BATTERY BACKUP SWITCHING IC
S-8426A Series
Rev.2.0_03
1. 2 Power supply variation: 6 V and 10 V square waves
Input
voltage
6V
Fast amplifier
10 V
VIN
Output
voltage
Overshoot
P.G.
VOUT
S-8426A
Seriers
VSS
COUT
Oscillo
scope
RL
Undershoot
Figure 25 Power Supply Variation:
Figure 26
Test Circuit
6 V and 10 V Square Waves
VOUT pin
COUT = 22 F, IOUT = 50 mA, Ta = 25 C
10 V
Input Voltage
10 V
6V
6V
(4 V/div)
Output Voltage
(50 mV/div)
t (100 s/div)
t (100 s/div)
Figure 27 Ringing Waveform of Power Supply Variation (VOUT Pin)
VRO pin
CRO = 22 F, IRO = 30 mA, Ta = 25 C
10 V
Input Voltage
10 V
6V
6V
(4 V/div)
Output Voltage
(50 mV/div)
t (100 s/div)
t (100 s/div)
Figure 28 Ringing Waveform of Power Supply Variation (VRO Pin)
18
BATTERY BACKUP SWITCHING IC
S-8426A Series
Rev.2.0_03
1. 3 Reference data: Dependency of output current (IOUT), load capacitance (COUT), input variation width
( VIN), temperature (Ta)
For reference, the following pages describe the results of measuring the ringing amounts at the VOUT and VRO
pins using the output current (IOUT), load capacitance (COUT), input variation width ( VIN), and temperature (Ta) as
parameters.
(1) IOUT Dependency
(a) VOUT pin
(b) VRO pin
COUT = 22 F, VIN = 6
10 V, Ta = 25 C
CRO = 22 F, VIN = 6
0.25
0.25
0.20
0.20
0.15
0.15
0.10
0.10
0.05
0.05
0.00
0
20
40
60
0.00
0
10 V, Ta = 25 C
20
IOUT (mA)
40
60
IRO (mA)
Figure30
Figure 29
Overshoot
Undershoot
(2) COUT Dependency
(a) VOUT pin
(b) VRO pin
IOUT = 50 mA, VIN = 6
10 V, Ta = 25 C
IRO = 30 mA, VIN = 6
0.50
0.50
0.40
0.40
0.30
0.30
0.20
0.20
0.10
0.10
0.00
0
10
20
30
COUT ( F)
Figure 31
40
50
0.00
0
10
20
10 V, Ta = 25 C
30
40
50
CRO ( F)
Figure32
Overshoot
Undershoot
19
BATTERY BACKUP SWITCHING IC
S-8426A Series
Rev.2.0_03
(3) VIN Dependency
VIN shows the difference between the low voltage fixed to 6 V and the high voltage.
For example, VIN = 2 V means the difference between 6 V and 8 V.
(a) VOUT pin
(b) VRO pin
IOUT = 50 mA, COUT = 22 F, Ta = 25 C
IRO = 30 mA, CRO = 22 F, Ta = 25 C
0.30
0.30
0.25
0.25
0.20
0.20
0.15
0.15
0.10
0.10
0.05
0.05
0.00
0.00
0
1
2
3
4
5
0
1
2
VIN (V)
3
4
5
VIN (V)
Figure34
Figure 33
Overshoot
Undershoot
(4) Temperature Dependency
(a) VOUT pin
VIN = 6 10 V, IOUT = 50 mA, COUT = 22 F
0.30
(b) VRO pin
VIN = 6
0.25
0.25
0.20
0.20
0.15
0.15
0.10
0.10
0.05
0.05
0.00
10 V, IRO = 30 mA, CRO = 22 F
0.30
0.00
50
0
50
Ta ( C)
Figure 35
100
50
0
50
100
Ta ( C)
Figure 36
Overshoot
Undershoot
20
BATTERY BACKUP SWITCHING IC
S-8426A Series
Rev.2.0_03
2.
Load Transient Response Based on Output Current Fluctuation
The overshoot and undershoot are caused in the output voltage if the output current fluctuates between 10 A and
50 mA (VRO is between 10 A and 30 mA) while the input voltage is constant. Figure 37 shows the output voltage
variation due to the output current. Figure 38 shows the test circuit for reference. The latter half of this section
describes ringing waveform and parameter dependency.
Input
voltage
50 mA
VIN
VOUT
S-8426A Series
10 A
VSS
Overshoot
Output
voltage
Figure 37
Oscillo
scope
COUT
Undershoot
Output Voltage Variation due to Output Current
Figure 38 Test Circuit
2. 1 Load Variation
Figure 39 shows the ringing waveforms at the VOUT pin and Figure 40 shows the ringing waveforms at the VRO
pin due to the load variation, respectively.
VOUT pin
VIN = 6.0 V, COUT = 22 F, Ta = 25 C
50 mA
Output current
50 mA
10 A
10 A
Output voltage
(50 mV/div)
t (50 s/div)
t (500 ms/div)
Figure 39 Ringing Waveform due to Load Variation (VOUT Pin)
VRO pin
VIN = 6.0 V, CRO = 22 F, Ta = 25 C
30 mA
Output current
30 mA
10 A
10 A
Output voltage
(20 mV/div)
t (20 ms/div)
t (50 s/div)
Figure 40 Ringing Waveform due to Load Variation (VRO Pin)
21
BATTERY BACKUP SWITCHING IC
S-8426A Series
Rev.2.0_03
2. 2 Reference data: Dependency of input voltage (VIN), load capacitance (COUT), output variation width
( IOUT), and temperature (Ta)
(1) VIN Dependency
(a) VOUT pin
COUT = 22 F, IOUT = 50 mA
10 A, Ta = 25 C
(b) VRO pin
CRO = 22 F, IRO = 30 mA
0.12
0.12
0.10
0.10
0.08
0.08
0.06
0.06
0.04
0.04
0.02
0.02
0.00
4
5
6
7
8
9
10
0.00
4
5
VIN (V)
10 A, Ta = 25 C
6
7
8
9
10
VIN (V)
Figure 42
Figure 41
Overshoot
Undershoot
(2) COUT Dependency
(a) VOUT pin
(b) VRO pin
VIN = 6.0 V, IOUT = 50 mA
10 A, Ta = 25 C
VIN = 6.0 V, IRO = 30 mA
0.60
0.30
0.50
0.25
0.40
0.20
0.30
0.15
0.20
0.10
0.10
0.05
0.00
0
10
20
30
COUT ( F)
Figure 43
40
50
0.00
0
10
10 A, Ta = 25 C
20
30
40
50
CRO ( F)
Figure 44
Overshoot
Undershoot
22
BATTERY BACKUP SWITCHING IC
S-8426A Series
Rev.2.0_03
(3) IOUT Dependency
IOUT and IRO show the fluctuation between the low current stabilized at 10
example, IOUT = 10 mA means a fluctuation between 10 A and 10 mA.
(a) VOUT pin
(b) VRO pin
CRO = 22 F, VIN = 6.0 V, Ta = 25 C
COUT = 22 F, VIN = 6.0 V, Ta = 25 C
0.12
0.12
0.10
0.10
0.08
0.08
0.06
0.06
0.04
0.04
0.02
0.02
0.00
0
10
20
30
40
50
A and the high current. For
60
0.00
0
10
20
30
40
50
60
IRO (mA)
IOUT (mA)
Figure 46
Figure 45
Overshoot
Undershoot
(4) Temperature Dependency
(a) VOUT pin
VIN = 6.0 V, IOUT = 50 mA
10 A, COUT = 22 F
(b) VRO pin
VIN = 6.0 V, IRO = 30 mA
0.16
0.08
0.14
0.07
0.12
0.06
0.10
0.05
0.08
0.04
0.06
0.03
0.04
0.02
0.02
0.01
0.00
0.00
50
0
50
Ta ( C)
Figure 47
100
50
10 A, CRO = 22 F
0
50
100
Ta ( C)
Figure 48
Overshoot
Undershoot
Caution 1. Be sure to add a 10 F or more capacitor to the VOUT and VRO pins.
2. The above connections and values will not guarantee correct operation. Before setting these
values, perform sufficient evaluation on the application to be actually used.
23
BATTERY BACKUP SWITCHING IC
S-8426A Series
Rev.2.0_03
Characteristics (Typical Data)
1.
Voltage Regulator Unit (VRO VOUT
5.0 V)
1. 1 Input Voltage (VIN) vs. Output Voltage (VRO) Characteristics (REG1)
85 C
(1) Ta
(2) Ta
25 C
5.2
5.2
5.0
5.0
4.8
4.8
IRO = 10 mA
IRO = 30 mA
IRO = 50 mA
IRO = 70 mA
IRO = 90 mA
4.6
4.4
4.2
4.0
4.0
6.0
5.0
IRO = 10 mA
IRO = 30 mA
IRO = 50 mA
IRO = 70 mA
IRO = 90 mA
4.6
4.4
4.2
4.0
4.0
7.0
5.0
VIN [V]
(3) Ta
6.0
7.0
VIN [V]
40 C
5.2
5.0
IRO = 10 mA
IRO = 30 mA
IRO = 50 mA
IRO = 70 mA
IRO = 90 mA
4.8
4.6
4.4
4.2
4.0
4.0
6.0
5.0
7.0
VIN [V]
1. 2 Input Voltage (VIN) vs. Output Voltage (VOUT) Characteristics (REG2)
(1) Ta
85 C
(2) Ta
5.2
5.2
5.0
5.0
4.8
4.4
4.2
4.0
4.0
5.0
6.0
4.6
4.4
4.2
4.0
7.0
VIN [V]
(3) Ta
5.2
5.0
IOUT = 10 mA
IOUT = 30 mA
IOUT = 50 mA
IOUT = 70 mA
IOUT = 90 mA
4.6
4.4
4.2
4.0
4.0
5.0
6.0
VIN [V]
4.0
6.0
5.0
VIN [V]
40 C
4.8
IOUT = 10 mA
IOUT = 30 mA
IOUT = 50 mA
IOUT = 70 mA
IOUT = 90 mA
4.8
IOUT = 10 mA
IOUT = 30 mA
IOUT = 50 mA
IOUT = 70 mA
IOUT = 90 mA
4.6
24
25 C
7.0
7.0
BATTERY BACKUP SWITCHING IC
S-8426A Series
Rev.2.0_03
1.0
1.0
0.8
0.8
Ta = 85 C
Ta = 25 C
Ta = 40 C
0.6
0.4
0.6
Ta = 85 C
Ta = 25 C
Ta = 40 C
0.4
0.2
0.2
0
0
0
0.04
0.02
0
0.06
5.20
5.10
5.00
0.06
IOUT [A]
5.20
Ta = 40 C
Ta = 25 C
Ta = 85 C
VIN = 6 V
0.04
0.02
IRO [A]
5.10
Ta = 40 C
Ta = 25 C
Ta = 85 C
VIN = 6 V
5.00
4.90
4.90
4.80
4.80
4.70
4.70
1
100
10m
1
1
100
IRO [A]
10m
1
IOUT [A]
30
30
20
20
10
10
0
0
10
10
20
20
30
30
40
25
0
25
Ta [ C]
50
75 85
30
20
20
15
10
10
0
5
10
40
25
0
25
Ta [ C]
50
75 85
40
25
0
25
Ta [ C]
50
75 85
0
40
25
0
25
Ta [ C]
50
75 85
25
BATTERY BACKUP SWITCHING IC
S-8426A Series
Rev.2.0_03
40
40
30
30
20
20
10
10
0
0
40
2.
25
0
25
Ta [ C]
50
75 85
25
0
25
Ta [ C]
50
75 85
Voltage Detector
2. 1
CS Voltage Detector ( VDET1
4.5 V)
20
30
Ta = 25 C
25
10
20
0
VIN = 3 V
15
10
10
VIN = 1.7 V
5
20
0
40
25
0
25
Ta [ C]
50
75 85
40
25
0
25
Ta [ C]
50
75 85
10
8
6
4
2
0
26
40
0
1.0
2.0
VDS [V]
3.0
4.0
BATTERY BACKUP SWITCHING IC
S-8426A Series
Rev.2.0_03
2. 2
RESET Voltage Detector ( VDET2
2.9 V)
RESET
20
30
Ta = 25 C
25
10
VIN = 3 V
20
0
15
10
10
VIN = 1.7 V
5
20
0
40
25
0
25
Ta [ C]
50
75 85
40
25
0
25
Ta [ C]
50
75 85
0
1.0
2.0
VDS [V]
3.0
4.0
10
8
6
4
2
0
2. 3
PREEND Voltage Detector ( VDET3
2.1 V)
PREEND
30
20
Ta = 25 C
25
10
20
15
0
VIN = 2 V
10
10
5
VIN = 1.7 V
0
20
40
25
0
25
Ta [ C]
50
75 85
40
25
0
25
Ta [ C]
50
75 85
0
1.0
2.0
VDS [V]
3.0
4.0
10
8
6
4
2
0
27
BATTERY BACKUP SWITCHING IC
S-8426A Series
3.
Rev.2.0_03
Switch Unit
20
20
10
10
0
0
10
10
20
20
40
25
0
25
Ta [ C]
50
75 85
60
60
50
50
50
40
30
30
20
20
10
10
0
40
25
0
25
Ta [ C]
50
75 85
40
25
0
25
Ta [ C]
50
75 85
40
25
0
25
Ta [ C]
50
75 85
0
1
2
3
4
5
VBAT [V]
30
25
20
15
10
5
0
40
4.
25
0
50
75 85
Consumption Current
16
14
12
10
8
6
4
2
0
16
Ta = 85 C
Ta = 25 C
Ta = 40 C
12
8
4
0
0
28
25
Ta [ C]
2
4
6
8 10 12 14 16 18
VIN [V]
Disclaimers (Handling Precautions)
1.
All the information described herein (product data, specifications, figures, tables, programs, algorithms and application
circuit examples, etc.) is current as of publishing date of this document and is subject to change without notice.
2.
The circuit examples and the usages described herein are for reference only, and do not guarantee the success of
any specific mass-production design.
ABLIC Inc. is not responsible for damages caused by the reasons other than the products described herein
(hereinafter "the products") or infringement of third-party intellectual property right and any other right due to the use
of the information described herein.
3.
ABLIC Inc. is not responsible for damages caused by the incorrect information described herein.
4.
Be careful to use the products within their specified ranges. Pay special attention to the absolute maximum ratings,
operation voltage range and electrical characteristics, etc.
ABLIC Inc. is not responsible for damages caused by failures and / or accidents, etc. that occur due to the use of the
products outside their specified ranges.
5.
When using the products, confirm their applications, and the laws and regulations of the region or country where they
are used and verify suitability, safety and other factors for the intended use.
6.
When exporting the products, comply with the Foreign Exchange and Foreign Trade Act and all other export-related
laws, and follow the required procedures.
7.
The products must not be used or provided (exported) for the purposes of the development of weapons of mass
destruction or military use. ABLIC Inc. is not responsible for any provision (export) to those whose purpose is to
develop, manufacture, use or store nuclear, biological or chemical weapons, missiles, or other military use.
8.
The products are not designed to be used as part of any device or equipment that may affect the human body, human
life, or assets (such as medical equipment, disaster prevention systems, security systems, combustion control
systems, infrastructure control systems, vehicle equipment, traffic systems, in-vehicle equipment, aviation equipment,
aerospace equipment, and nuclear-related equipment), excluding when specified for in-vehicle use or other uses. Do
not apply the products to the above listed devices and equipments without prior written permission by ABLIC Inc.
Especially, the products cannot be used for life support devices, devices implanted in the human body and devices
that directly affect human life, etc.
Prior consultation with our sales office is required when considering the above uses.
ABLIC Inc. is not responsible for damages caused by unauthorized or unspecified use of our products.
9.
Semiconductor products may fail or malfunction with some probability.
The user of the products should therefore take responsibility to give thorough consideration to safety design including
redundancy, fire spread prevention measures, and malfunction prevention to prevent accidents causing injury or
death, fires and social damage, etc. that may ensue from the products' failure or malfunction.
The entire system must be sufficiently evaluated and applied on customer's own responsibility.
10. The products are not designed to be radiation-proof. The necessary radiation measures should be taken in the
product design by the customer depending on the intended use.
11. The products do not affect human health under normal use. However, they contain chemical substances and heavy
metals and should therefore not be put in the mouth. The fracture surfaces of wafers and chips may be sharp. Be
careful when handling these with the bare hands to prevent injuries, etc.
12. When disposing of the products, comply with the laws and ordinances of the country or region where they are used.
13. The information described herein contains copyright information and know-how of ABLIC Inc.
The information described herein does not convey any license under any intellectual property rights or any other
rights belonging to ABLIC Inc. or a third party. Reproduction or copying of the information from this document or any
part of this document described herein for the purpose of disclosing it to a third-party without the express permission
of ABLIC Inc. is strictly prohibited.
14. For more details on the information described herein, contact our sales office.
2.2-2018.06
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