Rev. 7.2
_10
SMALL PACKAGE PWM/PFM CONTROL
STEP-UP SWITCHING REGULATOR
S-8324/8328 Series
Features
•
•
Low voltage operation:
0.9 V (I
OUT
=1 mA, 50 kHz and 100 kHz models)
Low current consumption:
During operation: 17.2
µA
(typ.)
(V
OUT
= 3 V, 50 kHz)
During shutdown: 0.5
µA
(max.)
Low Input current:
10.4
µA
( typ.)
(V
OUT
= 3 V, 50 kHz, no load)
PR
•
•
•
•
•
•
•
EXT
VSS
•
•
TI
NU
Duty ratio:
During PWM control: 15 to 83% typ.
(15 to 78% for 250kHz model)
During PFM control: 15 % typ.
ED
Applications
•
•
•
Power supplies for portable equipment such as pagers, handy calculators, and remote controllers
Constant voltage power supplies for cameras, video equipment, and communications equipment
Block Diagram
(1) S-8324 Series (Types A, C, H)
ON
Power supply for microcomputers
SC
CONT
VOUT
OD
UC
•
•
•
PWM
control
circuit
Soft start circuit
ON/ OFF
PWM
control
circuit
Soft start circuit
The S-8324/8328 is a series of CMOS PWM/PFM-control step-up
switching regulators which mainly consist of a reference voltage source,
an oscillation circuit, a power MOS FET (S-8324 Series) and an error
amplifier. The new method PWM/PFM control circuit automatically
switches the control method according to the current load, offering
products of a wide range, high efficiency. A step-up switching regulator is
constructed by externally connecting only a coil, a capacitor and a diode
to the S-8324 Series. This feature, along with its small package and low
current consumption, makes the S-8324 Series ideal for the power supply
of portable equipment. For applications requiring a high output current,
products used with an external transistor (S-8328 Series) are also
available.
External parts: coil, diode, and capacitor only
(a transistor is needed for the S-8328 Series.)
Output voltage: accuracy of
±2.4%
Oscillation frequency:
30 kHz, 50 kHz, 100 kHz, and 250 kHz
Software start function is built-in
Shutdown function
External transistor type is available (S-8328 Series)
SOT-23-5 small plastic package
SOT-23-3 small plastic package
SOT-89-3 miniature power molded plastic package
Step-down and invert type are also available.
(2) S-8328 Series (Types B, H)
DI
VREF
PWM
control
circuit
+
-
Soft start circuit
T
+
-
+
-
VOUT
VREF
VSS
ON/ OFF
(3) S-8324 Series (Types D, J)
CONT
VDD
PWM
control
circuit
Soft start circuit
VSS
VOUT
(4) S-8328 Series (Types E, J)
VOUT
VREF
+
-
VDD
EXT
VREF
VSS
Figure 1 Block Diagram
Seiko Instruments Inc.
1
SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR
S-8324/8328 Series
Selection Guide
1. Product Name
Rev. 7.2
_10
S-832 x x xx xx - xxx - T2
Tape Specification
Product name (abbreviation)
Package name (abbreviation)
MA : SOT-23-3 (without shutdown function)
MC : SOT-23-5 (with shutdown function, V
DD
/V
OUT
separate product)
UA : SOT-89-3 (without shutdown function)
Output voltage (symbol)
×10
Product category
A : Normal product, fosc=50 kHz (S-8324 only)
B : Normal product, fosc=100 kHz (S-8328 only)
C : For pagers, fosc=30 kHz (S-8324 only)
D : V
DD
/V
OUT
separate product, fosc=50 kHz (S-8324 only)
E : V
DD
/V
OUT
separate product, fosc=100 kHz (S-8328 only)
H : Normal product, fosc=250 kHz (S-8324/8)
J : V
DD
/V
OUT
separate product, fosc=250 kHz (S-8324/8)
Power transistor
4: Built-in PWM/PFM control switch.
8: PWM/PFM control switch with an external transistor.
TI
NU
Built In power with external Switching Shutdown V
DD
/V
OUT
frequency function separate Package
Product Name
transistor
power
Application
(KHz)
transistor
type
S-8324AxxMC
Yes
50
Yes
SOT-23-5 With a shutdown function
S-8324AxxMA
Yes
50
SOT-23-3 without shutdown function
S-8324AxxUA
Yes
50
SOT-89-3 without shutdown function
S-8324DxxMC
Yes
50
Yes
SOT-23-5 For variable output voltage by step-up DC/DC
converter and step-down inverted output DC/DC
converter with an external resistor
S-8324CxxMA
Yes
30
SOT-23-3 For pagers
S-8324HxxMC
Yes
250
Yes
SOT-23-5 With a shutdown function
S-8324JxxMC
Yes
250
Yes
SOT-23-5 For variable output voltage by step-up DC/DC
converter and step-down inverted output DC/DC
converter with an external resistor
S-8328BxxMC
Yes
100
Yes
SOT-23-5 For large load current with shutdown function
ED
Yes
Yes
S-8328BxxMA
S-8328BxxUA
S-8328ExxMC
S-8328HxxMC
S-8328JxxMC
Yes
Yes
Yes
Yes
Yes
100
100
100
250
250
ON
Yes
2
DI
SC
Seiko Instruments Inc.
PR
SOT-23-3 For large load current without shutdown function
SOT-89-3 For large load current without shutdown function
SOT-23-5 For variable output voltage by step-up DC/DC
converter with an external resistor
SOT-23-5 For large load current without shutdown function
SOT-23-5 For variable output voltage by step-up DC/DC
converter with an external resistor
OD
UC
T
Rev. 7.2
-10
SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR
S-8324/8328 Series
3. Product Name List
Output voltage
(V)
2.0
2.5
2.7
2.8
3.0
3.3
5.0
S-8324AxxMC
Series
S-8324A25MC-EOF-T2
S-8324A27MC-EOH-T2
S-8324A28MC-EOI-T2
S-8324A30MC-EOK-T2
S-8324A33MC-EON-T2
S-8324A50MC-EPE-T2
S-8324AxxMA
Series
S-8324A25MA-EOF-T2
S-8324A27MA-EOH-T2
S-8324A30MA-EOK-T2
S-8324A33MA-EON-T2
S-8324A50MA-EPE-T2
S-8324AxxUA
S-8324CxxMA
S-8324DxxMC
Series
Series
Series
S-8324D20MC-E2A-T2
S-8324A25UA-EOF-T2 S-8324C25MA-EQF-T2
S-8324A27UA-EOH-T2 S-8324C27MA-EQH-T2
S-8324A28UA-EOI-T2
S-8324A30UA-EOK-T2 S-8324C30MA-EQK-T2 S-8424D30MC-E2K-T2
S-8324A33UA-EON-T2
S-8324A50UA-EPE-T2
S-8324D50MC-E4E-T2
Consult our sales person for products with an output voltage other than specified above.
DI
SC
Output voltage
S-8328HxxMC
(V)
Series
2.5
S-8328H25MC-FYF-T2
3.0
S-8328H30MC-FYK-T2
3.2
S-8328H32MC-FYM-T2
3.3
S-8328H33MC-FYN-T2
5.0
S-8328H50MC-FZE-T2
5.5
S-8328H55MC-FZJ-T2
ON
TI
NU
Output voltage
(V)
2.0
2.4
2.5
2.7
2.8
3.0
3.2
3.3
3.4
3.6
3.8
4.9
5.0
5.1
5.2
5.4
5.5
S-8328BxxMC
Series
S-8328B24MC-EWE-T2
S-8328B25MC-EWF-T2
S-8328B27MC-EWH-T2
S-8328B28MC-EWI-T2
S-8328B30MC-EWK-T2
S-8328B32MC-EWM-T2
S-8328B33MC-EWN-T2
S-8328B34MC-EWO-T2
S-8328B36MC-EWQ-T2
S-8328B38MC-EWS-T2
S-8328B49MC-EXD-T2
S-8328B50MC-EXE-T2
S-8328B51MC-EXF-T2
S-8328B52MC-EXG-T2
S-8328B54MC-EXI-T2
S-8328B55MC-EXJ-T2
S-8328BxxMA
Series
S-8328B25MA-EWF-T2
S-8328B27MA-EWH-T2
S-8328B30MA-EWK-T2
S-8328B33MA-EWN-T2
S-8328B50MA-EXE-T2
S-8328BxxUA
S-8328ExxMC
Series
Series
S-8328E20MC-EYA-T2
S-8328B25UA-EWF-T2
S-8328B27UA-EWH-T2
S-8328B30UA-EWK-T2
S-8328B33UA-EWN-T2
S-8328B50UA-EXE-T2 S-8328E50MC-E9E-T2
S-8328JxxMA
Series
S-8328J25MC-F2F-T2
S-8328J30MC-F2K-T2
S-8328J33MC-F2N-T2
S-8328J50MC-F3E-T2
Seiko Instruments Inc.
ED
PR
OD
UC
Output voltage
S-8324HxxMC
(V)
Series
2.5
3.0
S-8324H30MC-F6K-T2
3.3
S-8324H33MC-F6N-T2
5.0
S-8324H50MC-F7E-T2
5.2
S-8324H52MC-F7G-T2
5.3
S-8324H53MC-F7H-T2
5.4
S-8324H54MC-F7I-T2
5.5
S-8324H55MC-F7J-T2
S-8324JxxMC
Series
S-8324J25MC-FUF-T2
S-8324J30MC-FUK-T2
S-8324J33MC-FUN-T2
S-8324J50MC-FVE-T2
T
3
SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR
S-8324/8328 Series
Pin Assignment
5
SOT-23-5
Top view
4
SOT-23-3
Top view
1
2
3
1
3
Figure 2
Product Names; S-8324AXxxMC / S-8328BxxMC
S-8324HxxMC / S-8328HxxMC
Package;
SOT-23-5
Pin No.
1
Functions
Shutdown pin
ON / OFF “H”: normal operation
(stepping up operation)
“L”: stop stepping up
(whole circuit stop)
VOUT Output voltage pin and power
supply pin
-
N.C. (Non Connection)
VSS
GND pin
CONT External inductor connection
pin (for S-8324 Series)
EXT
External transistor connection
pin (for S-8328 Series)
Pin name
Product Names; S-8324DxxMC / S-8328ExxMC
S-8324JxxMC / S-8328JxxMC
Package;
SOT-23-5
Pin No.
1
2
3
4
5
Pin name
VOUT
VDD
-
VSS
CONT
EXT
2
SOT-89-3
Top view
Rev. 7.2
_10
1
2
3
2
3
4
5
3
Absolute Maximum Ratings
Note:
the limit of the protection circuit should not be applied to.
DI
Although the IC contains protection circuit against static electricity, excessive static
electricity or voltage which exceeds
(Unless otherwise specified: Ta=25°C)
Symbol
V
OUT
, V
DD
V
ON/OFF
V
CONT
I
CONT
V
EXT
I
EXT
PD
SOT-89-3
SOT-23-5, SOT-23-3
Operating temperature
Storage temperature
T
OPR
T
STG
Ratings
V
SS
+11
V
ss
-0.3 to V
SS
+11
V
SS
+11
300
V
ss
-0.3 to V
OUT
+0.3
±50
500
150
-40 to +85
-40 to +125
°C
°C
Unit
V
V
V
mA
V
mA
mW
Parameter
VOUT, VDD pin voltage
ON/OFF pin voltage
CONT pin voltage
CONT pin current
EXT pin voltage
EXT pin current
Power dissipation
4
SC
ON
TI
NU
Pin No.
1
2
Pin name
Functions
VSS
GND pin
VOUT Output voltage pin and power
supply pin
CONT External inductor connection
pin (for S-8324 Series)
EXT
External transistor connection
pin (for S-8328 Series)
Seiko Instruments Inc.
ED
Product Names; S-8324AXXMA/S-8324AxxUA / S-8324CxxMA
S-8328BxxMA / S-8328BxxUA
Packages;
SOT-23-3, SOT-89-3
PR
OD
UC
Functions
Output voltage pin
Power supply pin
N.C. (Non Connection)
GND pin
External inductor connection
pin (for S-8324 Series)
External transistor connection
pin (for S-8328 Series)
T
Rev. 7.2
-10
SMALL PACKAGE PWM/PFM CONTROL STEP-UP SWITCHING REGULATOR
S-8324/8328 Series
Electrical Characteristics
1-1. S-8324AxxMC
Parameter
Output voltage
Symbol
V
OUT
Conditions
S-8324A50MC
S-8324A33MC
S-8324A30MC
S-8324A28MC
S-8324A27MC
S-8324A25MC
I
OUT
=1 mA
No external parts, voltage applied to V
OUT
CONT pulled up to 5 V by 10 kΩ
I
OUT
=1 mA, Measured by decreasing V
IN
voltage gradually
No load
S-8324A50MC
S-8324A33MC
S-8324A30MC
S-8324A28MC
S-8324A27MC
S-8324A25MC
V
OUT
=output voltage×0.95
S-8324A50MC
S-8324A33MC
S-8324A30MC
S-8324A28MC
S-8324A27MC
S-8324A25MC
V
OUT
=output voltage+0.5
S-8324A50MC
S-8324A33MC
S-8324A30MC
S-8324A28MC
S-8324A27MC
S-8324A25MC
V
ON/OFF
=0 V
Min.
4.880
3.221
2.928
2.733
2.635
2.440
0.7
(Unless otherwise specified: Ta=25
°C)
Typ.
Max.
Unit
Test circuit
5.000
3.300
3.000
2.800
2.700
2.500
10.5
10.4
10.4
10.5
10.5
10.5
30.2
19.1
17.2
16.1
15.5
14.3
3.5
3.3
3.2
3.2
3.2
3.2
182
125
125
98
98
98
30
30
±0.25
±0.17
±0.15
±0.14
±0.14
±0.13
50
83
15
6.0
87
83
83
79
79
79
5.120
3.379
3.072
2.867
2.765
2.560
9
0.9
0.8
21.1
20.8
20.7
21.0
21.1
21.0
50.3
31.8
28.7
26.8
25.9
23.9
6.9
6.5
6.4
6.4
6.4
6.3
0.5
1.0
60
60
57.5
90
24
0.3
0.2
12.0
ms
%
1
V
2
µA
V
1
Input voltage
Operation start voltage
Oscillation start voltage
Operation holding voltage
Input current at no load
V
IN
V
ST1
V
ST2
V
HLD
I
IN
2
1
Current consumption 1
I
SS1
OD
UC
T
2
Current consumption 2
I
SS2
TI
NU
ED
Current consumption during
shutdown
Switching current
I
SSS
I
SW
PR
V
CONT
=0.4 V
S-8324A50MC
S-8324A33MC
S-8324A30MC
S-8324A28MC
S-8324A27MC
S-8324A25MC
Switching transistor leak
current
Line regulation
Load regulation
Output voltage
temperature
coefficient
I
SWQ
V
OUT
= V
CONT
=10 V
114
78
78
61
61
61
42.5
75
5
0.75
3.0
mA
µA
mV
mV/°C
1
Oscillation frequency
Max duty ratio
PWM/PFM control switch
duty ratio
Shutdown pin
Input voltage
(ON/OFF type)
Soft start time
Efficiency
∆V
OUT1
V
IN
=output voltage×0.4 to
×0.6
∆V
OUT2
I
OUT
=10µA to I
OUT
(below)
×1.25
∆V
OUT
/∆Ta Ta=-40°C to +85°C
S-8324A50MC
S-8324A33MC
S-8324A30MC
S-8324A28MC
S-8324A27MC
S-8324A25MC
fosc
V
OUT
=output voltage×0.95
Measured waveform at CONT pin
MaxDuty V
OUT
=output voltage×0.95
Measured waveform at CONT pin
PFMDuty V
IN
= output voltage -0.1 V
No load
V
SH
V
OUT
=output voltage×0.95
Judged the oscillation at CONT pin
V
SL1
V
OUT
=output voltage×0.95
When
V
OUT
≥1.5
V
V
SL2
Judged the stop of oscillation When
at CONT pin
V
OUT
<1.5 V
t
SS
EFFI
S-8324A50MC
S-8324A33MC
S-8324A30MC
S-8324A28MC
S-8324A27MC
S-8324A25MC
ON
kHz
%
2
SC
1
External parts used:
-Coil:
CD54 (100
µH)
of Sumida Corporation
-Diode:
MA720 (Schottky type) of Matsushita Electric Industrial Co., Ltd.
-Capacitor: F93 (16 V, 22
µF,
tantalum type) of Nichicon Corporation
Applied V
IN
=output voltage×0.6, I
OUT
=output voltage/250
Ω
The shutdown pin is connected to VOUT pin.
Note 1: The output voltage specified above is the typical value.
DI
Seiko Instruments Inc.
5