Epson S1F76680 User manual
NOTICE
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S1F76680 Technical Manual (Rev.1.22) EPSON i
Table of Contents
1. DESCRIPTION ................................................................................................................1
2. FEATURES......................................................................................................................1
3. BLOCK DIAGRAM ..........................................................................................................2
4. DESCRIPTION OF BLOCK DIAGRAM...........................................................................3
5. PIN ASSIGNMENT ..........................................................................................................4
6. PIN DESCRIPTION .........................................................................................................5
7. OPERATIONAL AND FUNCTIONAL DESCRIPTION.....................................................7
7.1 Activation sequence .....................................................................................................................7
7.2 Setting and operating state..........................................................................................................8
7.3 LED current setting.......................................................................................................................8
7.3.1 Setting of maximum current value ............................................................................................8
7.3.2 Setting of automatic luminance control.....................................................................................9
7.4 I2C slave function........................................................................................................................17
7.5 Other functions ...........................................................................................................................19
8. ABSOLUTE MAXIMUM RATINGS ................................................................................20
9. ELECTRICAL CHARACTERISTICS .............................................................................21
10. EXTERNAL CONNECTION DIAGRAM ......................................................................22
10.1 Standard Connection Examples ..............................................................................................22
10.2 Recommended connection parts.............................................................................................23
<Precautions> ..................................................................................................................24
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1. DESCRIPTION
S1F76680 Technical Manual (Rev.1.22) EPSON 1
1. DESCRIPTION
S1F76680 is a LED driver that can drive four (three) white LEDs lamps for backlighting in parallel
connection.
Necessary power is supplied to LED by the charge pump type DC/DC converter incorporated in S1F76680.
Also, the charge pump type DC/DC converter selects 1x or1.5x voltages on its own according to necessity.
Maximum driving current to LED can be set with one external resistor.
With S1F76680, LED’s current value is changed in harmony with ambient brightness level, when connected
with an external luminance sensor.
In this IC, a two-wire serial interface I2C-Bus slave function is contained, and the current value in accordance
with the ambient brightness can be set with a register of I2C.
Allowing to configure the backlight that automatically selects optimal LED current value in accordance with
thebrightness level of the surrounding environment, this function makes this device a optimal LED driver for
mobile devices realizing high viewability and low power consumption.
2. FEATURES
zDrives four (three) white LEDs lamps in parallel connection
zSets LED maximum current value with an external resistor
zPower saving operation due to booster magnification automatic switching function of an amp circuit
zDriving with the LED current value changed in accordance to the ambient brightness level (automatic
luminance control) when connected with a luminance sensor
zAllows setting of the automatic luminance control characteristic with I2C
zEnable automatic luminance control/imperative fixed current selection with I2C
zAcquires the information on ambient brightness with I2C
zIncorporates a soft start circuit for activation with EN1 pin
zEnable automatic luminance control circuit activation/stop selection with EN2 pin
zAllows a drive at set maximum current with EN3 pin
zMass production form QFN5-32PIN (5.0mm ×5.0mm)
zNot radiation- or light-proofed
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3. BLOCK DIAGRAM
2 EPSON S1F76680 Technical Manual (Rev.1.22)
3. BLOCK DIAGRAM
S1F76680
Charge pump
Automatic
luminance
control
I
2
C-Bus serial
interface
LED drive
r
VOUT
CVOUT
LED4
LED3
VSS3
LED2
LED1
AOUT
RLED
CLED
CLED
VREF
CVREF
EN1
EN2
EN3
VDD1
VSS1
CVDD
C1P
C1N
C2P
C2N
C1
C2
VDD2
VSS2
Sensor
PDOUT
RPD
PD
CPD
SAMPL
VDDL
CVDDL
SCL
SDA
RESET
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4. DESCRIPTION OF BLOCK DIAGRAM
S1F76680 Technical Manual (Rev.1.22) EPSON 3
4. DESCRIPTION OF BLOCK DIAGRAM
(1) Charge pump
The charge pump is a circuit that generates voltage required for driving LED at VOUT pin.
As a pump-up capacitor required to operate the DC/DC converter, connect capacitors C1 and C2 with
C1P, C1N, C2P and C2N pins respectively.
Connect CVOUT as a storage capacitor for booster voltage generated at VOUT pin.
(2) Automatic luminance control
A circuit that determines the LED current value in accordance with the ambient brightness.
The ambient brightness can be evaluated by connecting a luminance sensor between PD pin and VSS
(GND), and an external resistor between PDOUT pin and PD pin.
(3) I2C -Bus serial interface
Advanced setting to this IC (selection of automatic luminance control operating status, characteristic
setting, reading of brightness information, etc) can be performed externally by reading /writing an
assigned register.
Since I2C on this IC only has slave function, control should be carried out externally by the master
function.
(4) LED driver
The LED driver drives four (three) white LEDs lamps in parallel connection.
Connect it with RLED, a resistor for maximum current setting.
The LED driver drives LED based on the settings of I2C, automatic luminance control and RLED.
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5. PIN ASSIGNMENT
4 EPSON S1F76680 Technical Manual (Rev.1.22)
5. PIN ASSIGNMENT
(QFN5-32PIN)
PIN No.
Pin Name I/O QFN5-32 Function
(test)
-
1 *Since this is a test pin, be sure to keep it “OPEN.”
(test)
-
2 *Since this is a test pin, be sure to keep it “OPEN.”
(test)
-
3 *Since this is a test pin, be sure to keep it “OPEN.”
EN3 I 4 Automatic luminance control/forced full lighting select pin. It is pulled down Internally.
VSS2
-
5 Ground pin.
(test)
-
6 *Since this is a test pin, be sure to keep it “OPEN.”
VDDL I 7 Input power supply pin for I2C I/O.
EN2 I 8 Automatic luminance control circuit activation/stop select pin. It is pulled down internally.
SCL I 9 I2C clock input pin.
SDA I/O 10 I2C data I/O pin.
RESET I 11 I2C reset (register initialization) pin
SAMPL I 12 Brightness evaluation sampling cycle select pin. It is pulled up internally.
VDD2
-
13 Input power supply pin.
PD I 14 Sensor connect pin.
PDOUT O 15 Sense resistor connect pin.
CLED O 16 Pin that connects to capacitor for LED current change delay
EN1 I 17 Input pin for activating IC. It is pulled down internally.
VREF O 18 Internal reference voltage pin.
AOUT O 19 Pin that connects to resistor for LED maximum current setting.
LED1 I 20 LED1 connect pin.
LED2 I 21 LED2 connect pin.
VSS3
-
22 Ground pin.
LED3 I 23 LED3 connect pin.
LED4 I 24
LED4 connect pin. *Be sure to connect this pin to ground when using three LEDs only.
(test)
-
25 *Since this is a test pin, be sure to keep it “OPEN.”
VSS1
-
26 Ground pin.
C1N
-
27 Pump-up capacitor C1 connect pin.
C1P
-
28 Pump-up capacitor C1 connect pin.
VOUT O 29 LED drive voltage output pin (LED common anode)
C2P
-
30 Pump-up capacitor C2 connect pin.
C2N
-
31 Pump-up capacitor C2 connect pin.
VDD1
-
32 Input power supply pin.
* EXPOSED DIE ATTACH PAD (refer to the outline drawing in No.P28) in the rear surface metal part of QFN5-32 package is
grounded to the same potential as VSS1=VSS2=VSS3.
Set the rear surface metal part to the open or grounding.
9 16
1
8
32 25
17
24
(test)
(test)
(test)
EN3
VSS2
(test)
VDDL
EN2
SD
A
RESET
SAMPL
VDD2
PD
PDOUT
CLED
LED4
LED3
VSS3
LED2
LED1
A
OUT
VREF
EN1
VDD1
C2N
C2P
VOUT
C1P
C1N
VSS1
(
test
)
S1F76680
SCL
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6. PIN DESCRIPTION
S1F76680 Technical Manual (Rev.1.22) EPSON 5
6. PIN DESCRIPTION
(1) Power Supply Pin
Pin Name PIN No.
(QFN5-32) Function
VDD1
VDD2
32
13
Power supply pin.
Supply voltage that obtains VDD1 = VDD2 ≥VDDL.
Since VDD1 is a power supply pin for the charge pump circuit, connect a bypass
capacitor CVDD immediately next to the VDD1 pin.
VDDL 7 Power supply pin for I2C I/O signal interface.
Supply voltage that obtains VDD1 = VDD2 ≥VDDL.
Connect a bypass capacitor CVDDL immediately next to VDDL pin.
VSS1
VSS2
VSS3
26
5
22
Ground pin.
(2) Input pin
1
Pin Name PIN No.
(QFN5-32) Function
EN1 17 Input pin for activating IC. It is pulled down internally.
This IC is set to the standby mode as EN1=L is selected.Whenever starting this IC
from the standby mode, change the state of EN1 from L to H. When EN1=L, too, also
allows input to and output from I2C circuit.The standby current value depends on the
setting of the EN2 pin to be described later or I2C register (SEN2). (See
No.P22)Setting of EN2 (SEN)-L, in which the standby current value is reduce, is
recommended for the standby mode.
EN1 (with pull-down) Function
L Standby state
H Circuit operating state
EN2 8 Input pin that selects activation/stop state for the automatic luminance control circuit.
It is pulled down internally.
The automatic luminance control circuit operates based on the setting of this EN2 pin
or that of I2C register (SEN2), which will be explained later.
If you do not select the operating state of the automatic luminance control circuit with
the EN2 pin, fix EN2 pin to LOW, and select the operating state with I2C register
(SEN2).
EN2 (with pull-down) Function
L Automatic luminance control circuit stop state
H Automatic luminance control circuit activated state
EN3 4 Forced full lighting select pin.
It is pulled down internally.
Fix EN3 pin to LOW when activating automatic luminance control.
If EN3 pin is fixed to HIGH, LED will light at maximum luminance regardless of the
setting of EN2.
EN3 (with pull-down) Function
L Automatic luminance control mode
H Forced full lighting mode
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6. PIN DESCRIPTION
6 EPSON S1F76680 Technical Manual (Rev.1.22)
(3) Input pin
2
Pin Name PIN No.
(QFN5-32) Function
SCL 9 I2C clock input pin.
SDA 10 I2C data input pin.
RESET 11 I2C register hard reset pin.
Cancel the reset after VDDL has risen.
RESET Function
L Resets I2C register
H Exits reset
SAMPL 12 Brightness evaluation sampling cycle select pin.
This pin is pulled up to VDD1=VDD2 level in the IC.
SAMPLE (with pull-up) Sampling cycle (TSAMPL)
H 655msec
L 1310msec
(4) Pin for charge pump circuit
Pin Name PIN No.
(QFN5-32) Function
C1N
C1P
27
28
Pump-up capacitor C1 connect pin.
Pump-up capacitor C1 connect pin.
C2N
C2P
31
30
Pump-up capacitor C2 connect pin.
Pump-up capacitor C2 connect pin.
VOUT 29 LED drive voltage output pin (LED common anode)
(5) Automatic luminance control and LED
Pin Name PIN No.
(QFN5-32) Function
PDOUT 15 Sense resistor connect pin.
PD 14 Sensor connect pin.
CLED 16 Pin that connects to capacitor for delaying LED current change
It is possible to add delay to the LED current change waveform by connecting an
external capacitor CLED with this pin.
(Connection of CLED=1µF is recommended)
LED1
LED2
LED3
LED4
20
21
23
24
LED 1 cathode connect pin.
LED 2 cathode connect pin.
LED 3 cathode connect pin.
LED 4 cathode connect pin.
*Connect this pin to ground when using three LED lamps only.
AOUT 19 Connect pin for LED maximum current setting resistor
(6) Miscellaneous
Pin Name PIN No.
(QFN5-32) Function
VREF 18 Internal reference voltage pin.
Connect capacitor CVREF immediately next to VREF pin.
(test)
(test)
(test)
(test)
(test)
1
2
3
6
25
Test pin.
*Set it to “OPEN.”
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7. OPERATIONAL AND FUNCTIONAL DESCRIPTION
S1F76680 Technical Manual (Rev.1.22) EPSON 7
7. OPERATIONAL AND FUNCTIONAL DESCRIPTION
7.1 Activation sequence
S1F76680 activation sequence is shown below.
1VDD1 and VDD2 start. (The battery voltage is supplied.)
2VDDL starts. (It is possible to start this at the same time as 1.)
3RESET = Low →High, and the resetting is cancelled.
Resetting of the I2C register is cancelled, and SCL and SDA are become effective.
4Start EN1. S1F76680 starts operating from the standby status.
The software start begins. (It is possible to start 1and 2at the same time.)
5After the software start period ends, the setting to turn on the LED will become effective.
[Input]
VDD1
VDD2
VDDL
RESET
EN1
LED lighting setting
NLED
EN2(SEN2)
EN3
SCL/SDA
[Output]
VOUT
Softstart
Softstart period Tss
After it ends for the softstart period
LED lighting set effective
Reset release
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7. OPERATIONAL AND FUNCTIONAL DESCRIPTION
8 EPSON S1F76680 Technical Manual (Rev.1.22)
7.2 Setting and operating state
EN1 EN2
*1 EN3 NLED
(I2C register)
Operating state
(After completion of soft start)
L X *2 X X Standby
H L L L LED lights off
H X H X LED lights up 1(At maximum current)
H H L L LED lights up 2(Under automatic luminance control)
H X L H LED lights up 3(At fixed current set in the register)
*1 EN2=H when either EN2 pin or I2C register SEN2 (see No.P14) is set to HIGH.
*2 The standby current value depends on the setting of EN2 pin I2C register (SEN2). (See No.P21)
7.3 LED current setting
7.3.1 Setting of maximum current value
The LED’s maximum current value is determined by the resistance value of resistor RLED connected with
AOUT pin.
The current value that can be set with I2C register described later cannot exceed this maximum current value.
(The current value can be set in the unit of one 127th of ILEDmax)
Connect resistor RLED as shown below, and be sure connect it between AOUT pin and VSS3.
Determine RLED from the following formula:
RLED=200 / ILEDmax
Maximum current set value = ILEDmax (mA), resistance value = RLED (kΩ)
For example, when ILEDmax=20mA is to be set, RLED=10kΩ.
AOUT VSS3
RLED
S1F76680
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7. OPERATIONAL AND FUNCTIONAL DESCRIPTION
S1F76680 Technical Manual (Rev.1.22) EPSON 9
7.3.2 Setting of automatic luminance control
[1] Connection of a sensor
For enabling automatic luminance control, a luminance sensor and resistor have to be connected externally.
Connect the sensor between VSS2 and PD pin, and sense resistor RPD between PDOUT and PD pin as
shown below.
When current flowing to the sensor is assumed IPD, VPD=IPD×RPD is established. S1F76680 uses this
VPD to evaluate brightness on the scale of 1 to 16.
The voltage at PDOUT and PD pins is 0V in the standby state.
Measures, such as shorter wiring between the sensor and sense resistor and S1F76680, stable VSS2 level
supply, etc, are required to avoid noise influence as much as possible.
It is recommended that CPD, a capacitor in the range from 0.1 to 1µF, be connected between VPD and
PDOUT pin as shown below as a measure.
[2] Selection of brightness evaluation sampling cycle
The S1F76680 sensor evaluates brightness in the brightness evaluation sampling cycle (TSAMPL).
The following values can be selected for the sampling cycle by setting SAMPL pin.
When using default sampling cycle (655msec), set SAMPL pin to “OPEN.”
SAMPL pin setting Sampling cycle (TSAMPL)
H (pulled up) 655msec
L 1310msec
* This pin is pulled up to VDD1=VDD2 level in the IC.
RPD
PDOUT
VSS2
CPD
VPD
IPD
S1F76680
PD
Sensor
Senso
r
Brightness
evaluation
LED current
settin
g
table LED driver
Brightness evaluation
Sampling cycle TSAMPL
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7. OPERATIONAL AND FUNCTIONAL DESCRIPTION
10 EPSON S1F76680 Technical Manual (Rev.1.22)
[3] Selection of the change time of the automatic luminance control current
S1F76680 judges brightness at every sampling cycle and then automatically changes LED current so that it
may correspond to the brightness.
When the automatic luminescence control is turned on, LED current value changes in a unit of 1/127 of
ILEDmax.
You can set the current change time from the 1AH at an address (to be described later) of I2C-Bus.
Independent setup is available for the increased current (TUP) and decreased current (TDW).
zWaveform of LED current changes in the automatic luminescence control
zCurrent change time selection register used in the automatic luminescence control
Register
TDW setting register TUP setting register
Address Item
D7 D6 D5 D4 D3 D2 D1 D0
Remarks
Register
name TDW3 TDW2 TDW1 TDW0 TUP3 TUP2 TUP1 TUP0
R/W R/W R/W R/W R/W R/W R/W R/W R/W
1AH
Initial value 0 1 1 1 0 1 0 1
-
zCurrent change time setting table
Change time 4-bit register setting
State of
selection TDW3
TUP3
TDW2
TUP2
TDW1
TUP1
TDW0
TUP0
Change time (Unit) Remarks
0 0 0 0 0 0.32 msec
1 0 0 0 1 0.64 msec
2 0 0 1 0 1.28 msec
3 0 0 1 1 2.56 msec
4 0 1 0 0 5.12 msec
5 0 1 0 1 10.24 msec TUP initial value
6 0 1 1 0 20.48 msec
7 0 1 1 1 40.96 msec TDW initial value
8 1 0 0 0 81.92 msec
9 1 0 0 1 163.84 msec
10 1 0 1 0 327.68 msec
11 1 0 1 1 655.36 msec
12 1 1 0 0 1.31 sec
13 1 1 0 1 2.62 sec
14 1 1 1 0 5.24 sec
15 1 1 1 1 10.48 sec
TUP TDW
ILED
ILED Max.
×
1/127
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7. OPERATIONAL AND FUNCTIONAL DESCRIPTION
S1F76680 Technical Manual (Rev.1.22) EPSON 11
[4] LED lighting sequence
Delay between the startup and LED lighting varies as shown below depending on the operating state.
zIn the case of LED lighting 1(Max. current) and LED lighting 3(fixed current set from the register)
zIn the case of LED lighting 2(Automatic luminescence control)
When lighting LED automatically after startup, a delay of TLEDON2 occurs until LED is lighted.
* You can cut the lighting delay time short during the automatic luminescence control mode by combining
two operations as shown above and then lighting LED with the fixed current.
Switching from the fixed current to the automatic luminescence control must be done after making sure
that the time of TLEDON4>TLEDON1+TELDON3 and TLEDON4>TLEDON2 have elapsed.
EN1
EN3/NLED
ILED (LED current)
TLEDON1 TLEDON3
EN1
EN2
(
SEN2
)
ILED (LED current)
TLEDON2
EN1
EN3/
(
SEN2
)
ILED (LED current)
TLEDON1
EN3/NLED TLEDON4
TLEDON3
TLEDON2
Fixed current
A
utomatic luminescence current
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7. OPERATIONAL AND FUNCTIONAL DESCRIPTION
12 EPSON S1F76680 Technical Manual (Rev.1.22)
When SAMPL=H
(Pull up) SAMPL=L Remarks
TLEDON1(msec) Max. 5msec+TUP
TLEDON2(msec) Max. 1180msec+TUP Max. 2360msec+TUP
TUP is selected from the current
change time setting table
(No.P11)
TLEDON3(msec) Max. 2100msec CLED=1.0µF
ILED 0%→90%,NLED=127
After LED has been lit, change of TUP becomes available from 1AH register at an address (to be described
later) of I2C-Bus.
[5] Delay in LED current change
S1F76680 allows providing delay to the LED current change waveform and thus realizing a smoother
current change by connecting the capacitor CLED to CLED pin. Connection of CLED=1µF is
recommended.
zLED current change waveform
CLED connect
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7. OPERATIONAL AND FUNCTIONAL DESCRIPTION
S1F76680 Technical Manual (Rev.1.22) EPSON 13
[6] Constant setting
Ambient luminance evaluated by a luminance sensor and sensor current IPD typically shows the following
inclination.
S1F76680 evaluates ambient brightness using value of sensor’s VPD on the scale of 1 to 16.
The following table shows relation between VPD and brightness.
VPD(V) Brightness
Brightness 1
Brightness 2
Brightness 3
Brightness 4
Brightness 5
Brightness 6
Brightness 7
Brightness 8
Brightness 9
Brightness 10
Brightness 11
Brightness 12
Brightness 13
Brightness 14
Brightness 15
Brightness 16
Dark
(low sensor current)
Bright
(high sensor current)
VPDn : Threshold of brigtness n and brightness n+1
Sensor current IPD [µA] log
Ambient luminance - Sensor current IPD
Ambient luminance [lx] log
10 100 1000 10000
VPD1=0.003
VPD2=0.004
VPD3=0.006
VPD4=0.010
VPD5=0.016
VPD6=0.026
VPD7=0.040
VPD8=0.063
VPD9=0.079
VPD10=0.126
VPD11=0.173
VPD12=0.299
VPD13=0.472
VPD14=0.787
VPD15=1.197
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7. OPERATIONAL AND FUNCTIONAL DESCRIPTION
14 EPSON S1F76680 Technical Manual (Rev.1.22)
The appropriate RPD is determined by the characteristic of the luminance sensor being used and this IC’s
VPD for brightness evaluation.
The following table shows IPDs for brightness evaluation with sense resistor RPD=100kΩ.
VPD(V) Brightness
RPD(kΩ) Brightness is judged. IPD(µA)
IPDn=VPDn/RPD
Brightness 1
Brightness 2
Brightness 3
Brightness 4
Brightness 5
Brightness 6
Brightness 7
Brightness 8
Brightness 9
Brightness 10
Brightness 11
Brightness 12
Brightness 13
Brightness 14
Brightness 15
Brightness 16
Dark
(low sensor current)
Bright
(high sensor current)
100
IPD(µA)=VPD÷RPD
VPD(mV)
Bright Bright Bright
・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・
Bright Bright
ness1 ness2 ness3 ness15 ness16
VPD1=0.003
VPD2=0.004
VPD3=0.006
VPD4=0.010
VPD5=0.016
VPD6=0.026
VPD7=0.040
VPD8=0.063
VPD9=0.079
VPD10=0.126
VPD11=0.173
VPD12=0.299
VPD13=0.472
VPD14=0.787
VPD15=1.197
IPD1=0.03
IPD2=0.04
IPD3=0.06
IPD4=0.10
IPD5=0.16
IPD6=0.26
IPD7=0.40
IPD8=0.63
IPD9=0.79
IPD10=1.26
IPD11=1.73
IPD12=2.99
IPD13=4.72
IPD14=7.87
IPD15=11.97
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7. OPERATIONAL AND FUNCTIONAL DESCRIPTION
S1F76680 Technical Manual (Rev.1.22) EPSON 15
Next, determine the LED current values at respective brightness levels.
Set the current values to the following addresses with I2C-Bus, which will be explained later.
It is possible to set 128 gradations (SLED), from 0 to 127, for the LED current value and SLED (0 to 127) is
set by setting 7-bit value, from D0 (LSB) to D6 (MSB), to each address.
D7 is a dummy.
When automatic luminance control is activated, LED drive current changes gradually between current values
set to respective address.
This gradual change of the current value realizes the comfortable display during automatic luminance control.
The current value can be obtained from the following formula:
ILED(mA)=ILEDmax ×SLED / 127
* Note, however, that SLED (0 to 3) are not lighted but they are turned off.
Note that setting SLED (0 to 3) lights off LED.
When ILEDmax=20mA
If (D7,D6,D5,D4,D3,D2,D1,D0)=(X,1,1,1,1,1,1,1) is input, SLED=127, therefore, ILED=20mA ×127/127 =
20mA, which means LED is driven at maximum current.
If (D7,D6,D5,D4,D3,D2,D1,D0)=(X,0,0,0,0,0,0,0) is input, SLED=0, therefore, ILED=20mA ×0/127=0mA,
which means LED goes off.
* When variations in luminescence result from the minute LED lighting current setting (SLED being set to
small), you can specify to increase the LED current value.
If LED setting address is not newly set, SLED will be operated at register default value.
Brightness LED current setting
address Register default value
Brightness 1 02H 13
Brightness 2 03H 18
Brightness 3 04H 38
Brightness 4 05H 42
Brightness 5 06H 52
Brightness 6 07H 62
Brightness 7 08H 68
Brightness 8 09H 85
Brightness 9 0AH 100
Brightness 10 0BH 108
Brightness 11 0CH 127
Brightness 12 0DH 127
Brightness 13 0EH 127
Brightness 14 0FH 125
Brightness 15 10H 119
Brightness 16
Dark
(low sensor current)
Bright
(high sensor current) 11H 105
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7. OPERATIONAL AND FUNCTIONAL DESCRIPTION
16 EPSON S1F76680 Technical Manual (Rev.1.22)
The following table shows an example of customized LED current setting for automatic luminance control.
Brightness LED current setting
address Setup example:
Brightness 1 02H 15
Brightness 2 03H 28
Brightness 3 04H 36
Brightness 4 05H 44
Brightness 5 06H 53
Brightness 6 07H 62
Brightness 7 08H 72
Brightness 8 09H 85
Brightness 9 0AH 95
Brightness 10 0BH 105
Brightness 11 0CH 108
Brightness 12 0DH 108
Brightness 13 0EH 108
Brightness 14 0FH 108
Brightness 15 10H 108
Brightness 16
Dark
(low sensor current)
Bright
(high sensor current) 11H 108
An example of LED current setting
VPD
120
100
80
60
40
20
0
SLED
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