Epson S1F76640 User manual

Rev.1.5
S1F76640
Technical Manual

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©SEIKO EPSON CORPORATION 2007,All rights reserved.

Configuration of product number
!DEVICES
S1 F 76640 M 0C0 000
Packing specifications
Specifications
Shape
(M:SOP, SSOP)
Model number
Model name
(F : Power Supply)
Product classification
(S1:Semiconductors)

CONTENTS
1. DESCRIPTION........................................................................................................................................1
2. FEATURES..............................................................................................................................................1
3. BLOCK DIAGRAM................................................................................................................................2
4. PIN DESCRIPTION................................................................................................................................3
4.1 Pin Assignment............................................................................................................................................3
4.2 Pin Functions ...............................................................................................................................................4
5. FUNCTIONAL DESCRIPTION............................................................................................................5
6. ELECTRICAL CHARACTERISTICS .................................................................................................8
6.1 Absolute Maximum Ratings ........................................................................................................................8
6.2 Recommended Operating Conditions ..........................................................................................................9
6.3 Electrical Characteristics............................................................................................................................10
6.4 Measuring Circuit ......................................................................................................................................11
7. CHARACTERISTIC DATA.................................................................................................................12
8. APPLIED CIRCUIT EXAMPLES ......................................................................................................17
S1F76640 Technical Manual (Rev.1.5) EPSON i

1. DESCRIPTION
S1F76640 Technical Manual (Rev.1.5) EPSON 1
1. DESCRIPTION
The S1F76640 is a high efficient and low power consuming CMOS DC-DC converter.
It consists of two components: a booster and a stabilizer.
The booster provides double boosting output (3.6 to 11V), triple boosting output (5.4 to 16.5V) or quadruple
boosting output (7.2 to 22V) for input voltage (1.8 to -5.5V).
Moreover, the use of external parts such as diode and capacitor provides boosting of higher magnification.
The voltage stabilizer enables you to set to any output voltage.
It also provides three types of negative temperature gradients for voltage stabilization output, and it is most
suitable for LCD power.
The S1F76640 enables you to drive an IC (liquid crystal driver, analog IC, etc.) that would usually require
another power supply in addition to the logic main power, using a single power supply. Therefore, it is suitable
for supplying micro-power to compact electrical devices such as hand-held computers with low power
consumption.
2. FEATURES
(1) Highly efficient and low power consuming CMOS DC-DC converter
(2) Easy conversion from input voltage VDD (+3.3V) to three types of positive voltages
Output 2 ×VDD (+6.6V), 3 ×VDD (+9.9V), and 4 ×VDD (+13.2V) from input VDD (+3.3V)
(3) The use of external parts such as diode and capacitor provides boosting of higher magnification
(4) Built-in output voltage stabilizer
- Any output voltage settable with external resistor
(5) Output current: Max. 20mA (VDD = +5V)
(6) Efficiency of power conversion: typ.95 %
(7) Three types of reference voltage with negative temperature gradient characteristics suitable for LCD drive
power supply.
(8) Power-off operation by external signal
- Static current for power-off: Max. 2μA
(9) Boosting of higher magnification through serial connection
(10) Low voltage operation: Most suitable for battery drive
(11) Built-in CR oscillation circuit
(12) SSOP2-16 pins
(13) This IC is not designed to be radiation resistant

03. BLOCK DIAGRAM
2 EPSON S1F76640 Technical Manual (Rev.1.5)
3. BLOCK DIAGRAM
OSC1
VSS(GND)
OSC2
VDD
TC2
TC1
XPOFF
RV
VREG
VOUT
CR
oscillation
circuit
Reference voltage generato
r
Voltage stabilize
r
CAP1+
CAP3+
CAP2+
CAP2−
CAP1−
Booste
r
Voltage converte
r
VRI
Temperature gradient selection circuit
Stabilize
r
Fig.3.1 Block Diagram

4. PIN DESCRIPTION
S1F76640 Technical Manual (Rev.1.5) EPSON 3
4. PIN DESCRIPTION
4.1 Pin Assignment
SSOP2-16PIN
1
2
3
4
5
6
7
8
RV
VREG
TC1
TC2
XPOFF
(GND)VSS
OSC1
OSC2
16
15
14
13
12
11
10
9
VRI
VOUT
CAP3
+
CAP2
+
CAP2
−
CAP1
+
CAP1
−
VDD
Fig.4.1 SSOP2-16 Pin Assignment

04. PIN DESCRIPTION
4 EPSON S1F76640 Technical Manual (Rev.1.5)
4.2 Pin Functions
Pin Name Pin No. Function
CAP1+11 Positive pin connected to pump-up capacitor for double boosting
CAP1−10 Negative pin connected to pump-up capacitor for double boosting
Next-stage clock for serial connection
CAP2+13 Positive pin connected to pump-up capacitor for triple boosting
CAP2−12 Negative pin connected to pump-up capacitor for 3rd boosting
Output pin for double boosting (shorted with VOUT)
CAP3+14 Positive pin connected to pump-up capacitor for quadruple boosting
Output pin for triple boosting (shorted with VOUT)
TC1 3 Temperature gradient selection pin
TC2 4 Temperature gradient selection pin
VDD 9 Power supply pin (Positive side, system VCC)
VOUT 15 Output pin for quadruple boosting
VRI 16 Stabilizer input pin
VREG 2 Stabilizing voltage output pin
RV 1 Stabilizing voltage adjustment pin
Adjusts the VREG output voltage by connecting an intermediate tap of the external
volume (3-pin resistor) connected between the VDD and VREG pins to the RV pin.
XPOFF 5 VREG output ON/OFF control pin
Controls S1F76640M0C power-off (VREG output power off) by inputting a control
signal from the XPOFF system to this pin.
OSC2 8 Pin connected to oscillation resistor
Opened for external clock operation.
OSC1 7 Pin connected to oscillation resistor
Functions as a clock input pin for external clock operation
VSS(GND) 6 Power supply pin (Negative side, system GND)

5. FUNCTIONAL DESCRIPTION
S1F76640 Technical Manual (Rev.1.5) EPSON 5
5. FUNCTIONAL DESCRIPTION
!CR oscillation circuit
The S1F76640 is equipped with a CR oscillation circuit as an internal oscillation circuit, connecting external
resistor ROSC for oscillation between the OSC1 and OSC2 pins (Fig.5.1).
ROSC
(Note 1)
OSC1
OSC2 Open
External clock
OSC1
OSC2
Fig.5.1 CR oscillation circuit Fig.5.2 External Clock Operation
Note 1: The oscillation frequency varies depending on the wiring capacity, so the wire between the OSC1 and
OSC2 pins and ROSC must be short as much as possible.
To set the external resistor ROSC, first obtain the oscillation frequency fOSC that satisfies the maximum
efficiency in Figures 7.12 and 7.13, and then obtain ROSC corresponding to the fOSC in Fig.7.1.
The relationship between ROSC and fOSC can be briefly expressed by the following equation on condition that
400kΩ<ROSC<2MΩ.
OSC
OSC f1
AR ・=(where A is a constant: GND = 0V, VDD = 5V, fOSC A = 2.0 ×1010 (Ω•Hz))
Therefore, the ROSC value can be obtained from the relational expression above.
(Recommended oscillation frequency: 10kHz to 30kHz (ROSC: 2MΩto 680kΩ)
For external clock operation, open the OSC2 pin as shown in Fig.5.2 and input external clocks (duty 50%) from
the OSC1 pin.

05. FUNCTIONAL DESCRIPTION
6 EPSON S1F76640 Technical Manual (Rev.1.5)
"Voltage converters (I) and (II)
Voltage converters (I) and (II) perform double boosting and triple boosting for input power voltage VDD using
clocks generated in the CR oscillation circuit.
For double boosting, the double input voltage is obtained from the Vout pin by connecting an external pump-up
capacitor between CAP1+ and CAP1- and jumpering between CAP2+, CAP3+ and VOUT.
For triple boosting, 3VDD is output from the VOUT pin by connecting an external pump-up capacitor between
CAP1+ and CAP1- and between CAP2+ and CAP2-, and connecting an external smoothing capacitor between
VDD and VOUT.
For quadruple boosting, 3VDD is output from the VOUT pin by connecting an external pump-up capacitor
between CAP1+ and CAP1- and between CAP2+ and CAP2-, and connecting an external smoothing capacitor
between VDD and VOUT.
Figures 5.3, 5.4 and 5.5 show the relationships between input and output voltages, using VSS = 0V and VDD =
5V.
VDD=5V
CAP1+=2VDD=10V
VSS=0V
VDD=5V
CAP2+=3VDD=15V
VSS=0V
VDD=5V
CAP3+=4VDD=20V
Note 2:
Note 3:
VSS=0V
Note 1:
Fig.5.3 Relationships between Fig.5.4 Relationships between Fig.5.5 Relationships
Double Boosting Voltages Triple Boosting Voltages between Quadruple
Boosting Voltages
Note 1: In triple boosting, the double boosting output (+10V) cannot be extracted from the CAP2+ pin.
Note 2: In quadruple boosting, the double boosting output (+10V) cannot be extracted from the CAP2+ pin.
Note 3: In quadruple boosting, the triple boosting output (+15V) cannot be extracted from the CAP3+ pin.
#Reference voltage generator, voltage stabilizer
The reference voltage generator generates a reference voltage required to operate the voltage stabilizer, and
provides a temperature gradient to the reference voltage.
There are three types of temperature gradients and the appropriate one is selected by a signal sent from the
temperature gradient selection circuit. The voltage stabilizer stabilizes boosting output voltage VOUT and
outputs any voltage.
As shown in Fig.5.5, the VREG output voltage can be set to any voltage between the reference voltage VRV and
VOUT by connecting the external resistor RRV and changing the voltage of the intermediate tap.
R1
VREG
VSS
X
POFF
RV
RRV
VREG =──── $VRV
R1
Control signal
RRV=100k
Ω
to 1M
Ω
Fig.5.6 Voltage Stabilizer
The voltage stabilizer, which contains the power-off function, enables VREG output ON/OFF control when the
signal is sent from the system (microprocessor, etc.).
When XPOFF = High (VDD), the VREG output is turned on; when XPOFF = Low (GND), it is turned off.
If the VREG output ON/OFF control is not necessary, XPOFF is fixed to High (VDD) as shown in Fig.4.5 (dashed
lines).

5. FUNCTIONAL DESCRIPTION
S1F76640 Technical Manual (Rev.1.5) EPSON 7
%Temperature gradient selection circuit
As shown in Table 5.1, the S1F76640 provides three types of temperature gradients suitable for LCD driving to
VREG output.
Table 5.1 Correspondence between Temperature Gradients and VREG Output ON/OFF
XPOFF
Note 1) TC2 Note 1) TC1 Note 1)
Temperature
gradient CT
Note 2) VREG output CR
oscillation
circuit Remarks
1(VDD) L(VSS) L(VSS) -0.40%/°C ON ON -
1(VDD) L(VSS) H(VOUT) -0.30%/°C ON ON -
1(VDD) H(VOUT) L(VSS) -0.50%/°C ON ON -
1(VDD) H(VOUT) H(VOUT) -0.50%/°C ON OFF
Serial connection
Note 4)
0(VSS) L(VSS) L(VSS) - OFF(Hi-Z) Note 3) OFF -
0(VSS) L(VSS) H(VOUT) - OFF(Hi-Z) Note 3) OFF -
0(VSS) H(VOUT) L(VSS) - OFF(Hi-Z) Note 3) OFF -
0(VSS) H(VOUT) H(VOUT) - OFF(Hi-Z) ON Boosting only Note 5)
Note 1: The high voltage is different between the XPOFF, TC2, and TC1 pins.
Note 2: The temperature gradient CT is defined in the following formula:
V
REG (50°C) - VREG (0°C) 1
CT= × ×100 (%/°C)
50°C - 0°C V
REG (25°C)
Example: When CT- = -0.3%/°C is selected;
if VREG output at Ta = 25°C is VREG (25°C) = 8V,
ΔVREG /ΔT = CT $|VREG (25°C) |= -0.3×10-2×8 = 24mV/°C is obtained,
the |VREG |value reduces 40mV each time the temperature rises by 1°C.
- VREG (25°C) = 10V results in Δ|VREG |/ΔT = 30mV/°C.
Note 3: When the power is off (VREG output: OFF, CR oscillation circuit: OFF), the VOUT output voltage is set
to VDD-0.5V.
Note 4: Selecting this mode for serial connection drives the next-stage IC with the first-stage clock, and
reduces the power consumption of the next-stage IC. (See item 8 - (4).)
Note 5: Select this mode for boosting operation only. It minimizes the current consumption.

06. ELECTRICAL CHARACTERISTICS
8 EPSON S1F76640 Technical Manual (Rev.1.5)
6. ELECTRICAL CHARACTERISTICS
6.1 Absolute Maximum Ratings
Standard value
Item Symbol
Min. Max.
Unit Remarks
Input power voltage VDD GND-0.3 24/N V VDD (N= 3, 4)
8 N = 3: Triple boosting
6 N = 4: Quadruple boosting
Input pin voltage VIGND-0.3 VDD-0.3 V 0SC1, XPOFF
GND-0.3 VOUT-0.3 V TC1, TC2, RV
Output voltage V0GND-0.3 24 V VOUT Note 3:
GND-0.3 VOUT V VREG Note 3:
Output pin voltage 1 V0C1 GND-0.3 VDD-0.3 V CAP1+, CAP2+, 0SC2
Output pin voltage 2 V0C2 GND-0.3 2×VDD-0.3 V CAP1-
Output pin voltage 3 V0C3 GND-0.3 3×VDD-0.3 V CAP2-
Output pin voltage 4 V0C4 GND-0.3 4×VDD-0.3 V CAP3-
Allowable dissipation Pd - 210 mW SSOP-16PIN
Operating temperature Topr -40 85 °C -
Storage temperature Tstg -55 150 °C -
Soldering temperature and time Tsol - 260"10 °C"s Lead part
Note 1: Use exceeding the absolute maximum ratings above may cause a permanent destruction of the IC.
A long-duration operation at the absolute maximum ratings may significantly decrease reliability.
Note 2: All the voltage values above are based on GND.
Note 3: The VOUT and VREG output pins output the boosted voltage and stabilized boosted-voltage.
No external voltage should therefore be applied to these pins. When being compelled to apply external
voltage to the pins for use, it must be in the allowable range of the rated voltages above.

6. ELECTRICAL CHARACTERISTICS
S1F76640 Technical Manual (Rev.1.5) EPSON 9
6.2 Recommended Operating Conditions
Standard value
Item Symbol
Min. Max.
Unit Remarks
Boosting start voltage VSAT1 1.8 - V ROSC=1MΩ, C4≥10μF
CL/C4≥1/20, Note 2)
VSAT2 2.2 - V ROSC=1MΩ
Boosting stop voltage VSTP - 1.8 V ROSC=1MΩ
Output load current IOUT - 20 mA -
fOSC 10 30 kHz - Oscillation frequency
External resistor for oscillation ROSC 680 2000 kΩ -
Boosting capacitor C1,C2,C3,C4 3.3 - μF -
Stabilization-output adjusting resistor RRV 100 1000 kΩ -
Note 1: All voltages are based on the condition that the VSS (GND) is equal to 0V.
Note 2: For low-voltage (VDD = 1.8 to 2.2V) operation, the recommended circuit is as follows:
1
2
3
4
5
6
7
8
RV
VREG
TC1
TC2
POFF
VSS
OSC1
OSC2
16
15
14
13
12
11
10
9
VRI
VOUT
CAP3
+
CAP2
+
CAP1
+
CAP2
−
CAP1
−
VDD
VI
C2
C1
C3
C4
D1
RL
CL
+
−
+
−
+
−
+
−
(D1 (VF(IF = 1mA)
≤
0.6V recommended)
Fig.6.2.1 Recommended Circuit for Low-voltage Operation (Example of Quadruple Booster Circuit)

06. ELECTRICAL CHARACTERISTICS
10 EPSON S1F76640 Technical Manual (Rev.1.5)
6.3 Electrical Characteristics
If not specified Ta=-40°C to +85°C VSS=0V､VDD=5V
Standard value
Symbol
Min. Typ. Max.
Unit Conditions Measuring
circuit
Item
Input power voltage VDD 1.8 - 5.5 V -
Output voltage VOUT - - 22 V -
VREG VRV - 22 V R=∞, RRv=1MΩ,
VOUT=22V
"
Stabilizer operating
voltage
VOUT VRV+2.5 - 22 V -
Booster current
consumption
Iopr1 - 30 60 μARL=∞, ROSC=1MΩ!
Stabilized circuit
current consumption
Iopr2 - 25 50 μARL=∞, VOUT=20V "
Static current IQ - - 2 μA TC2=TC1=VOUT, Rl=∞!
Oscillation frequency f0SC 14.0 17.5 21.0 kHZ ROSC=1MΩ!
Output impedance ROUT - 250 350 ΩIOUT=10mA !
Pef 90 95
- % IOUT=5mA !Boosting power
conversion efficiency
Note 2)
ΔVREG
ΔVOUT･VREG
0.1
- %/V 10V<VOUT<20V,
VREG=10V
RL=∞, Ta=25°C
"
Stabilization output
voltage variation
ΔVREG
ΔIOUT
- 5 - ΩVOUT=20V, VREG=15V
Ta=25°C, 0<IOUT<10Ma
TC1=VOUT, TC2=GND
"
Stabilization output
load variation Note
3)
RSAT
- 10 - ΩRSAT=Δ(VOUT-VREG)/
ΔIOUT
0<IOUT<10mA, RV=GND,
Ta=25°C
"
Stabilization output
saturated resistance
Note 4)
Reference voltage VRV0 1.70 1.90 2.20 V TC2=GND, TC1=VOUT,
Ta=25°C
"
VRV1 1.80 2.00 2.20 V TC2=TC1=GND,Ta=25°C
VRV2 1.50 1.60 1.80 V TC2=VOUT, TC1=GND,
Ta=25°C
Temperature CT0 -0.40 -0.30 -0.20 %/°CVDD=5V､VOUT=20V "
gradient CT1 -0.50 -0.40 -0.30 %/°C Note 5)
CT2 -0.60 -0.50 -0.40 %/°C
Input leak current IL - - 2 μA Poff, TC1, TC20SC1, and
RV pins
#
Note 1: All voltages are based on the condition that the VSS (GND) is equal to 0V.
Note 2: The values above indicate the conversion efficiency of the booster. When the stabilizer is active, the
loss is (VREG - VOUT) ×IOUT.
It is, therefore, recommended to use the method of reducing (VOUT - VREG) as much as possible.
If (VOUT - VOUT) ×IOUT is high, the stabilizer characteristics vary as the IC temperature rises.
Note 3: See Figures 7.15, 7.16, and 7.17.
Note 4: RSAT indicates the inclination shown in Fig.7.18; VOUT - Δ(VOUT - VREG) indicates the lower limit
voltage of the VREG output.
Note 5: The computational expression of CT is shown below:
V
REG (50°C) - VREG (0°C) 1
CT= × ×100 (%/°C)
50°C - 0°C V
REG (25°C)

6. ELECTRICAL CHARACTERISTICS
S1F76640 Technical Manual (Rev.1.5) EPSON 11
6.4 Measuring Circuit
!Booster circuit characteristics Measuring circuit
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
A
A
V
Iopr1
ROSC
IO
RL
C1
C2
C3 C4
VO
+
−
+
−
+
−
+
−
"Stabilization circuit characteristics Measuring circuit
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
A
V
VO
IOR1
R2
VI
RL
VREG
A
Iopr2 (excluding the current flowing
through R1, R2 and RL)
(RRV＝R1+R2)
#Input leak current Measuring circuit
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
A
Connected to each
measurement pin

07. CHARACTERISTIC DATA
12 EPSON S1F76640 Technical Manual (Rev.1.5)
7. CHARACTERISTIC DATA
1
10
100
1000
10 100 1000 10000
R
OSC
[ｋΩ]
f
osc [kHz]
V
DD
=2V
V
DD
=5V
V
DD
=3V
Ta=25°C
10
12
14
16
18
20
-40 -20 0 20 40 60 80 100
Ｔａ [°C]
f
osc [kHz]
V
DD
=5V
V
DD
=2V
V
DD
=3V
Fig.7.1 Oscillation frequency- External
resistor for oscillation
Fig.7.2 Oscillation frequency
0
10
20
30
40
50
60
70
0123456
VDD [V]
IOPR1 [μA]
f
OSC=8.75kHz
Ta=25°C
VDD=5V
C1 to C4=10μF
f
OSC=35kHz
f
OSC=17.5kHz
0
5
10
15
20
0102030
IO[mA]
VO[V]
Ta=25°C
VDD=5V
C1 to C4=10μF
Quadruple
boosting Triple
boosting Double
boosting
Fig.7.3 Booster current consumption
- Input voltage
Fig.7.4 Output voltage (VO) - Output current !

7. CHARACTERISTIC DATA
S1F76640 Technical Manual (Rev.1.5) EPSON 13
0
2
4
6
8
10
12
0 5 10 15 20
IO[mA]
V
0
1
2
3
4
5
6
7
8
9
10
0246810
I
O
[m A]
VO[V]
Ta=25°C
V
DD
=2V
C1 to C4=10μF
Quadruple
boosting Triple
boosting
Double
boosting
Fig.7.5 Output voltage (VO) - Output current "Fig.7.6 Output voltage (VO) - Output current #
Fig.7.7 Output impedance - Input voltage !Fig.7.8 Output impedance - Input voltage "
0
100
200
300
400
500
600
700
0123456
VDD [V]
RO[Ω]
Ta=25°C
IO=5mA
Quadruple
boosting Triple
boosting
Double
boosting
0
100
200
300
400
500
600
700
0123456
VDD [V]
RO[Ω]
Ta=25°C
IO=10mA
Quadruple
boosting Triple
boosting
Double
boosting
O[V]
Quadruple
boosting
Ta=25°C
VDD=3V
C1 to C4=10μF
Triple
boosting Double
boosting

07. CHARACTERISTIC DATA
14 EPSON S1F76640 Technical Manual (Rev.1.5)
0
10
20
30
40
50
60
70
80
90
100
0102030
IO[mA]
Peff [%]
0
30
60
90
120
150
IDD [mA]
Ta=25°C
VDD=5V
C1 to C4=10μF
Quadruple
boosting
Pef f
Triple
boosting Pef f
Double
boosting Peff
Quadruple
boosting
Triple
boostin
g
IDD
Double
boosting IDD
0
10
20
30
40
50
60
70
80
90
100
0 5 10 15 20
IO[mA]
Peff [%]
0
10
20
30
40
50
60
70
80
90
100
IDD [mA]
Ta=25°C
VDD=3V
C1 to C4=10μF
Quadruple
boosting
Pef f
Triple
boosting Pef f
Double
boosting Pef f
Quadruple
boosting
Triple
boosting IDD
Double
boosting IDD
Fig.7.9 Boosting power conversion efficiency
- Output current !
Input current - Output current !
Fig.7.10 Boosting power conversion efficiency
-Outputcurrent"
Input current - Output current "
0
10
20
30
40
50
60
70
80
90
100
1 10 100 1000
fOSC [kHz]
Peff [%]
Ta=25°C
VDD=5V
C1 to C4=10μF
IO=10m A
IO=2mA
IO=5m
A
IO=20mA
0
10
20
30
40
50
60
70
80
90
100
012345678910
IO[mA]
Peff [%
0
10
20
30
40
50
IDD [mA]
Fig.7.11 Boosting power conversion efficiency
- Output current #
Input current - Output current #
Fig.7.12 Boosting power conversion efficiency
- Oscillation frequency !
]
Ta=25°C
VDD=2V
C1 to C4=10
Quadruple
boosting
Pe f f
Triple
boosting Pef f
Double
boosting Pef f
Quadruple
boosting IDD
Triple
boosting IDD
Double
boosting IDD
F
μ