○Product structure：Silicon monolithic integrated circuit ○This product is not designed for protection against radioactive rays.
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TSZ02201-0A0A2D300080-1-2
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TSZ22111･14･001
Multifunction LCD Segment Driver
BU97941FV MAX 104 segments (SEG26×COM4)
●Features
Integrated RAM for display data (DDRAM):
26 x 4 bit (Max 104 Segments)
LCD drive output:
4 Common output, 26 Segment output
Integrated 4ch LED driver circuit
Support standby mode
Integrated Power-on-Reset circuit (POR)
Integrated Oscillator circuit
No external component
Low power consumption design
Independent power supply for LCD driving
●Applications
Telephone
FAX
Portable equipment (POS, ECR, PDA etc.)
DSC
DVC
Car audio
Home electrical appliance
Meter equipment
etc.
●Key Specifications
■ Supply Voltage Range: +1.8V to +3.6V
■ LCD drive power supply Range: +2.7V to +5.5V
■ Operating Temperature Range: -40°C to +85°C
■ Max Segments: 104 Segments
■ Display Duty: Static, 1/3, 1/4 selectable
■ Bias: Static, 1/3
■ Interface: 3wire serial interface
●Package W (Typ.) x D (Typ.) x H (Max.)
●Typical Application Circuit
BU97941FV
Figure 1. Typical application circuit
SSOP-B40
13.60mm x 7.80mm x 2.00mm
Signal input from controller
*About resistor value:
Determine the optimal value
based on the applied curr
ent
With 25mA as max per 1 port
5.0V
3.3V
VLCD
VDD
CSB
SD
SCL
VSS
LCD
COM0
to
COM3
SEG0
to
SEG25
LED1
VLED=5.0V
LED2
LED3
LED4
BU97941FV
Datashee
t
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TSZ22111･15･001
BU97941FV MAX 104 segments (SEG26×COM4)
●Block Diagram / Pin Configuration / Pin Description
Figure 2. Block Diagram Figure 3. Pin Configuration (TOP VIEW)
Table 1 Pin Description
Pin Name
Pin No.
I/O
Setting
when not in
use
Function
CSB
26
I
VDD
Chip select: "L" active
SCL
27
I
VSS
Serial data transfer clock
SD
28
I
VSS
Input serial data
VDD
29
-
-
Power supply for LOGIC
VSS
25
-
-
External clock input terminal (for display/PWM using
selectable)
Support Hi-Z input mode at internal clock mode
VLCD
30
-
-
GND
COM0 to 3
31 to 34
O
OPEN
Power supply for LCD
SEG0 to 25
1 to 20
35 to 40
O
OPEN
COMMON output for LCD
LED1 to 4
21 to 24
O
OPEN
LED driver output
common
counter
OSCILLATOR
LCD
BIAS
SELECTOR
common
driver
Power On Reset
SD
SCL/CLKIN
VSS
VSS
COM0……COM3
SEG0……SEG25
IF FILTER
serial inter face
DDRAM
LCD voltage
Generator
Command register
Data Decoder
VLCD
CSB
VDD
Segment
driver
LED
Driver
LED4...LED1
External clock line
LED4
LED3
LED2
LED1
1
20
21
40
VSS
CSB
SCL
SD
VDD
VLCD
COM3
COM2
COM1
COM0
SEG4
SEG3
SEG1
SEG0
SEG5
SEG9
SEG10
SEG11
SEG12
SEG7
SEG8
SEG15
SEG16
SEG17
SEG18
SEG13
SEG14
SEG19
SEG20
SEG23
SEG24
SEG25
SEG21
SEG22
SEG6
SEG2
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TSZ22111･15･001
BU97941FV MAX 104 segments (SEG26×COM4)
●Absolute Maximum Ratings (VSS=0V)
Item
Symbol
Ratings
Unit
Remarks
Power supply Voltage1
VDD
-0.3 to +4.5
V
Power supply
Power supply Voltage2
VLCD
-0.5 to +7.0
V
Voltage for Liquid crystal Display
Power supply Voltage2
VLED
-0.5 to +7.0
V
Voltage for LED driving port terminal
Power Dissipation
Pd
0.8*1
W
Input Voltage Range
VIN
-0.5 to VDD+0.5
V
Operating Temperature
Range
Topr
-40 to +85
℃
Storage Temperature
Range
Tstg
-55 to +125
℃
Output Current
Iout1
5
mA
SEG Output
Iout2
5
mA
COM Output
Iout3
50
mA
LED Output (per 1 port)
*Decreases 8mW per 1℃ when using at 1 Ta=25℃ or higher. （During ROHM standard board mounting）
（Board size：74.2mm×74.2mm×1.6mm Material：FR4 Glass-epoxy board Copper foil： Land pattern only）
●Recommended Operating Ratings(Ta=-40°C to +85°C,VSS=0V)
Item
Symbol
MIN
TYP
MAX
Unit
Remarks
Power supply Voltage1
VDD
1.8
-
3.6
V
Power supply
Power supply Voltage2
VLCD
2.7
-
5.5
V
Voltage for Liquid crystal Display
Output Current
Iout1
-
-
25
mA
LED Output (per LED1 port)
Iout2
-
-
100
mA
LED Output (LED port current total sum)
●Electrical Characteristics
DC Characteristics (Ta=-40°C to +85°C、VDD=1.8V to 3.6V、VLCD=2.7V to 5.5V、VSS=0V )
Item
Symbol
Limit Value
Unit
Condition
MIN
TYP
MAX
“H” level input voltage
VIH
0.8VDD
-
VDD
V
SD, SCL, CSB
“L” level input voltage
VIL
VSS
-
0.2VDD
V
SD, SCL, CSB
Hysteresis width
VH
-
0.2
-
V
SCL, VDD=3.3V、Ta=25°C
“H” level input current
IIH1
-
-
5
uA
SD,SCL, CSB,
VI=3.6V
LED off leak
OFF LEAK
5
0
5
uA
LED VI=5.5V
“H” level output voltage
(*2)
VOH1
VLCD
-0.4
-
-
V
Iload=-50uA, VLCD=5.0V
SEG0 to SEG25
VOH2
VLCD
-0.4
-
-
V
Iload=-50uA, VLCD=5.0V、
COM0 to COM3
“L” level output voltage
(*2)
VOL1
-
-
0.4
V
Iload= 50uA, VLCD=5.0V、
SEG0 to SEG25
VOL2
-
-
0.4
V
Iload= 50uA, VLCD=5.0V、
COM0 to COM3
VOL4
-
0.11
0.5
V
Iload=20mA、VLCD=5.0V、
LED1 to 4
output voltage (*2)
VOUT1
2.73
3.33
3.93
V
Iload=+/-50uA, VLCD=5.0V, SEG0 to 25,
COM0 to 3
VOUT2
1.07
1.67
2.27
V
Iload=+/-50uA, VLCD=5.0V, SEG0 to 25,
COM0 to 3
Supply current (*1)
IstVDD
-
3
10
uA
Input pin ALL ‟L‟,
Display off, Oscillation off
IstVLCD
-
0.5
5
uA
Input pin ALL ‟L‟,
Display off, Oscillation off
IVDD1
-
8
15
uA
VDD=3.3V、Ta=25°C、
1/3bias、fFR=64Hz、Output open
IVLCD1
-
10
15
uA
VLCD=5.0V、Ta=25°C、
1/3bias、fFR=64Hz、Output open
＊1 During Power save mode 1、Frame inversion.
＊2 Iload：When setting the load of 1 pin only.
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TSZ22111･15･001
BU97941FV MAX 104 segments (SEG26×COM4)
●Electrical Characteristics – continued
Oscillation Frequency Characteristics (Ta=-40°C to +85°C、VDD=1.8V to 3.6V、VLCD=2.7V to 5.5V、VSS=0V )
Item
Symbol
Limit Value
Unit
Condition
MIN
TYP
MAX
Frame Frequency 1
fFR1
76.5
85
93.5
Hz
VDD=3.3V、Ta=25°C、fFR=85Hz setting
Frame Frequency 2
fFR2
68
85
97.0
Hz
VDD=2.5V to 3.6V fFR=85Hz setting
Frame Frequency 3
fFR3
59.7
-
68
Hz
VDD=1.8V to 2.5V fFR=85Hz setting
MPU Interface Characteristics (Ta=-40°C to +85°C、VDD=1.8V to 3.6V、VLCD=2.7V to 5.5V、VSS=0V )
Item
Symbol
Limit Value
Unit
Condition
MIN
TYP
MAX
Input Rise Time
ｔｒ
-
-
50
ns
Input Fall Time
ｔf
-
-
50
ns
SCL Cycle
tSCYC
250
-
-
ns
“H” SCL pulse width
tSHW
50
-
-
ns
“L” SCL pulse width
tSLW
50
-
-
ns
SD Setup Time
tSDS
50
-
-
ns
SD Hold Time
tSDH
50
-
-
ns
CSB Setup Time
tCSS
50
-
-
ns
CSB Hold Time
tCSH
50
-
-
ns
“H” CSB pulse width
tCHW
50
-
-
ns
Figure 4. Serial Interface Timing
CSB
SCL
SD
tCSH
tSCYC
tSLW
tSHW
tSDS
tSDH
tf
tr
tCSS
tCHW
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TSZ22111･15･001
BU97941FV MAX 104 segments (SEG26×COM4)
●I/O equivalent circuit
Figure 5. I/O equivalent circuit
●Example of recommended circuit
Figure 6. Recommended circuit example
VDD
VSS
VLCD
VSS
VLCD
SEG0-25
COM0-3
VSS
LED1-4
VSS
VDD
CSB, SD,
SCL,CLKIN
VSS
Signal input from controller
*About resistor value
Determine the optimal value
based on the applied curr
ent
With 25mA as max per 1 port
5.0V
3.3V
VLCD
VDD
CSB
SD
SCL
VSS
LCD
COM0
to
COM3
SEG0
to
SEG25
LED1
VLED=5.0V
LED2
LED3
LED4
BU97941FV
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TSZ22111･15･001
BU97941FV MAX 104 segments (SEG26×COM4)
●Function Description
○Command・Data Transfer Method
○3-SPI（3-wire Serial Interface）
This device is controlled by a 3-wire signal: CSB, SCL, SD.
First, Interface Counter is initialized with CSB=”H”.
Setting CSB = “L” enables SD and SCL inputs.
Each command starts with Command or data judgment bit (D/C) as MSB data,
followed by D6 to D0 (this is while CSB=”L).
Internal data is latched at the rising edge of SCL, then the data is converted to an 8-bit parallel data at the falling edge of
the 8th CLK.
When CSB changes from “L” to “H” and the data being transferred is less than 8 bits, command and data being
transferred will be cancelled.
To start sending command again, please set CSB to “L”. Then, be sure to input a 1-byte command .
Also, when DDRAM data becomes input state through RAMWR command, the device cannot accept command inputs.
In order to input again, please start up CSB.
If CSB is set to ”H”, the data input state is cancelled and if ”CSB” is set to ”L” again, command will be received.
Figure 7. 3-SPI Data Transfer Format
○ Write and Transfer Method of Display Data
This device has display data ram of 26×4＝104bit.
The handling of display data with write and the handling of DDRAM data and Address and display are as follows:
Binary 8-bit data is written to DDRAM. The starting address is set with the Address set command, and is automatically
incremented per 4bit data received.
Next, by transferring data, data can be written continuously to DDRAM.
(When continuously writing data to DDRAM, after writing to the final address 19h（SEG25）, address will return to 00h
(SEG0) through auto increment.)
DDRAM address
00
01
02
03
04
05
06
07
・・・
17h
18h
19h
BIT
0
a
e
i
m
COM0
1
b
f
j
n
COM1
2
c
g
k
o
COM2
3
d
h
l
p
COM3
SEG
0
SEG
1
SEG
2
SEG
3
SEG
4
SEG
5
SEG
6
SEG
7
SEG
23
SEG
24
SEG
25
D/C
D/C
D3
D6
D0
D0
D6
D6
D5
D4
D3
D1
D0
D/C
D4
D3
D2
D1
SCL
CSB
SD
D/C
3rd byte Command
D2
1st byte Command
2nd byte Command
D4
D6
D5
D1
D2
D5
10000011
1st Byte
Command
a b c d
e f g h i j k l m n o p
…
onwards
Display data
00000000
Address set
Command
10100000
RAM Write
2nd Byte
Command
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TSZ22111･15･001
BU97941FV MAX 104 segments (SEG26×COM4)
Writing to RAM is done per 4bit. When CSB is set to „H‟ and the data is less than 4 bits, the writing of RAM will be
cancelled. （Transfer of command is done per 8bit.）
Figure 8. Display Data Transfer Method
D0
D7
D5
Address 31h
Display data
D5
D6
1st byte Command / 2nd byte Command
D4
D3
D2
Address Set Command
D0
Internal Signal
RAM write
Address 00h
Address 01h
CSB
Address 00h
D4
D4
D2
D1
D5
D3
Internal Signal
RAM write
SCL
D7
D6
SD
1st byte Command / 2nd byte Command
Display data
Address 02h
D6
D5
D4
D3
D7
D1
Address Set Command
SCL
CSB
SD
D2
RAM WRITE Command
D5
D4
D3
D2
D1
D0
Returns to 0 through
auto increment
Command
Command
RAM WRITE Command
D7
D6
RAM write per 4bit
When CSB='H' is set and
less than 4bit, writing
is cancelled.
Address 00h
Address 30h
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TSZ22111･15･001
BU97941FV MAX 104 segments (SEG26×COM4)
○LCD Driver Bias / Duty Circuit
Voltage is generated for LCD driver.
Buffer amplifier is integrated with low power consumption possible.
＊Line and frame inversion can be set by MODESET command.
＊1/4duty, 1/3duty, and static duty can be set by DISCTL command.
For each liquid crystal display waveform, see ”Liquid crystal Display Waveform”.
○Reset Initial State
The default condition after executing Software Reset is as follows:
・ Display is turned OFF.
・ Each command register enters Reset state.
・ DDRAM address is initialized.
(DDRAM data is not initialized. Therefore, it is recommended to write initial values to all DDRAM before Display on.）
●Command / Function Table
Function Description Table
NO
Command
Function
1
Mode Set (MODESET)
Liquid crystal Display setting
2
Display control (DISCTL)
LCD setting1
3
Address set (ADSET)
LCD setting2
4
LED control (LEDCTL)
LED board ON/OFF setting
5
RAM WRITE (RAMWR)
RAM Write Start setting
6
All Pixel ON (APON)
All display ON
7
All Pixel OFF (APOFF)
All display OFF
8
All Pixel On/Off mode off (NORON)
Normal display APON/APOFF setting release）
9
Software Reset (SWRST)
Software reset
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TSZ22111･15･001
BU97941FV MAX 104 segments (SEG26×COM4)
●Command Description
D/C (MSB) is a bit for command or data judgment.
For details, see 3-wire Serial Interface Command, Data Transfer Method.
○Mode Set Command (MODESET)
MSB
LSB
D/C
D6
D5
D4
D3
D2
D1
D0
Hex
Reset
1st byte Command
1
0
0
0
0
0
0
1
81h
-
2nd byte Command
0
0
0
0
P3
P2
P1
P0
-
00h
Display setting
Setting
P3
Reset state
Display OFF
0
○
Display ON
1
Display OFF ： Oscillation circuit operation OFF, Liquid crystal power supply circuit operation OFF with frame
cycle. Display OFF state (Output：VSS level)
Display ON ： Oscillation circuit operation ON, Liquid crystal power supply circuit ON. Read operation from
DDRAM starts. Display ON state with frame cycle.
＊LED board is not affected by the ON/OFF state of Display.
The output state of LED port is determined by the setting of the LEDCTL command.
Liquid crystal Drive Waveform Setting
Setting
P2
Reset state
Frame inversion
0
○
Line inversion
1
Power save mode (Low current consumption mode) setting
Setting
P1
P0
Reset state
Power save mode1
0
0
○
Power save mode2
0
1
Normal mode
1
0
High power mode
1
1
＊Use high power mode at VLCD＞3V or higher.
(Reference Current Consumption Data)
Setting
Current
Consumption
Power save mode 1
×1.0
Power save mode 2
×1.7
Normal mode
×2.7
High power mode
×5.0
＊The current consumption data above is reference data and changes according to panel load.
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TSZ22111･15･001
BU97941FV MAX 104 segments (SEG26×COM4)
○Display control command (DISCTL)
MSB
LSB
D/C
D6
D5
D4
D3
D2
D1
D0
Hex
Reset
1st byte Command
1
0
0
0
0
0
1
0
82h
-
2nd byte Command
0
0
0
0
P3
P2
P1
P0
-
02h
Duty setting
Setting
P3
P2
Reset state
1/4duty (1/3bias)
0
0
○
1/3duty (1/3bias)
0
1
Static (1/1bias)
1
*
(*: Don‟t care)
At 1/3duty, the display / blink data for COM3 are invalid.
(COM3: same waveform with COM1)
At 1/1duty (Static), the display / blink data for COM1 to 3 are invalid.
(COM1 to 3: same waveform with COM0)
Be careful in sending display data.
For sample output waveform of SEG/COM with duty setting, see "Liquid crystal Display Waveform".
Frame Frequency Setting
Setting
(When 1/4,1/3,1/1duty)
P1
P0
Reset state
(128Hz, 130Hz, 128Hz)
0
0
(85Hz, 86hz, 64Hz)
0
1
○
(64Hz, 65Hz, 48Hz)
1
0
(51Hz, 52Hz, 32Hz)
1
1
The relationship with frame frequency (FR), internal osc frequency and dividing number is below:
DISCTL
(P1,P0)
Divide
FR [Hz]
1/4duty
1/3duty
1/1duty
1/4duty
1/3duty
1/1duty
(0,0)
160
156
160
128
131.3
128
(0,1)
240
237
320
85.3
86.4
64
(1,0)
320
315
428
64
65
47.9
(1,1)
400
393
640
51.2
52.1
32
When calculating the OSC frequency from the measurement value of frame frequency, use the following equation:
“ OSC frequency = Frame Frequency (Measurement value) × Dividing number”
Dividing number：Using the values of Frame Frequency setting (P1,P0) and duty setting(P3,P2), determine the
values from the table above.
Ex) (P1,P0) = (0,1) 、(P3,P2) = (0,1) ⇒ Dividing number= 237
＊1：The value of FR in the table above is the Frame Frequency calcuated as OSC Frequency = 20.48KHz (typ).
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TSZ22111･15･001
BU97941FV MAX 104 segments (SEG26×COM4)
○Address set command (ADSET)
MSB
LSB
MSB
D/C
D6
D5
D4
D3
D2
D1
D0
Hex
Reset
1st byte Command
1
0
0
0
0
0
1
1
83h
-
2nd byte Command
0
0
0
P4
P3
P2
P1
P0
-
00h
Sets the starting RAM address for normal display.
Address can be set from 00h to 1Bh.
Setting is prohibited for addresses not written above.
Address during Reset is 00h.
When writing to RAM, a separate RAM WRITE setting is needed.
○LED control command (LEDCTL)
MSB
LSB
MSB
D/C
D6
D5
D4
D3
D2
D1
D0
Hex
Reset
1st byte Command
1
0
0
0
0
1
0
1
85h
-
2nd byte Command
0
0
0
0
P3
P2
P1
P0
-
00h
Sets the driver of the LED port. Setting during Reset is 00h.
The relationship between each parameter and the Drive board is as follows:
LED1
P0
LED2
P1
LED3
P2
LED4
P3
LED ON
1
1
1
1
LED OFF
0
0
0
0
＊ Please input CSB="H" after LEDCTL command is issued.
To avoid noise and reset interface.
○RAM WRITE command (RAMWR)
MSB
LSB
D/C
D6
D5
D4
D3
D2
D1
D0
Hex
Reset
1st byte Command
1
0
1
0
0
0
0
0
A0h
-
2nd byte Command
Display data
Random
・・・・
n byte Command
Display data
Random
The input data after command setting is the data input for display.
Be sure to send this command after setting the ADSET command.
The display data is transferred per 4bit. (For details, see “Write and Transfer Method of Display Data.”)
○All Pixel ON command (APON)
MSB
LSB
D/C
D6
D5
D4
D3
D2
D1
D0
Hex
Reset
1st byte Command
1
0
0
1
0
0
0
1
91h
-
Regardless of the contents of DDRAM, the SEG output will enter all light up mode. (Pin that selects SEG output)
12/23
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TSZ22111･15･001
BU97941FV MAX 104 segments (SEG26×COM4)
○All Pixel OFF command (APOFF)
MSB
LSB
D/C
D6
D5
D4
D3
D2
D1
D0
Hex
Reset
1st byte Command
1
0
0
1
0
0
0
0
90h
-
Regardless of the contents of DDRAM, the SEG output will enter all light up mode. (Pin that selects SEG output)
○All Pixel ON/OFF mode off (NORON)
MSB
LSB
D/C
D6
D5
D4
D3
D2
D1
D0
Hex
Reset
1st byte Command
1
0
0
1
0
0
1
1
93h
-
APON / OFF mode is cancelled and switches to normal display mode. (Pin that selects SEG output)
After reset, NORON is set and becomes normal display state.
○Software Reset command (SWRST)
MSB
LSB
D/C
D6
D5
D4
D3
D2
D1
D0
Hex
Reset
1st byte Command
1
0
0
1
0
0
1
0
92h
-
Resets software. This IC is in reset state.
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TSZ22111･15･001
BU97941FV MAX 104 segments (SEG26×COM4)
●Liquid crystal Drive Waveform
Figure 9. LCD Drive Waveform during Line inversion Figure 10.LCD Drive Waveform during Frame inversion
1/4Duty
Line inversion
Frame inversion
1frame
1frame
COM0
COM0
COM1
COM1
COM2
COM2
COM3
COM3
SEGn
SEGn
SEGn+1
SEGn+1
SEGn+2
SEGn+2
SEGn+3
SEGn+3
stateA
stateA
(COM0-SEGn)
(COM0-SEGn)
stateB
stateB
(COM1-SEGn)
(COM1-SEGn)
COM1
stateB
COM2
COM3
SEGn+2
SEGn+3
COM0
stateA
SEGn
SEGn+1
SEGn+2
SEGn+3
COM3
stateA
SEGn
SEGn+1
COM0
COM1
COM2
stateB
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
Vreg
-Vreg
Vreg
-Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
Vreg
-Vreg
Vreg
-Vreg
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TSZ22111･15･001
BU97941FV MAX 104 segments (SEG26×COM4)
Figure 11. LCD Drive Waveform during Line inversion Figure 12. LCD Drive Waveform during Frame inversion
1/3Duty
Line inversion
Frame inversion
1frame
1frame
COM0
COM0
COM1
COM1
COM2
COM2
COM3
COM3
SEGn
SEGn
SEGn+1
SEGn+1
SEGn+2
SEGn+2
SEGn+3
SEGn+3
stateA
stateA
(COM0-SEGn)
(COM0-SEGn)
stateB
stateB
(COM1-SEGn)
(COM1-SEGn)
COM1
stateB
COM2
COM3
SEGn+2
SEGn+3
COM0
stateA
SEGn
SEGn+1
SEGn+2
SEGn+3
COM3
stateA
SEGn
SEGn+1
COM0
COM1
COM2
stateB
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
Vreg
-Vreg
Vreg
-Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
Vreg
-Vreg
Vreg
-Vreg
VSS
Vreg
When 1/3duty
COM3 waveform output is same as COM1
When 1/3duty
COM3 waveform output is same as COM1
When 1/3duty
COM3 waveform output
is same as COM1
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TSZ22111･15･001
BU97941FV MAX 104 segments (SEG26×COM4)
Figure 13.LCD Drive Waveform during Line inversion Figure 14. LCD Drive Waveform during Frame inversion
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
Vreg
-Vreg
Vreg
-Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
VSS
Vreg
Vreg
-Vreg
Vreg
-Vreg
VSS
Vreg
When 1/1duty (Static)
COM1 ： same waveform as COM0
COM2 ：same waveform as COM0
COM3 ：same waveform as COM0
When 1/1duty
(Static)
COM1 / COM0
is same waveform
COM2 / COM0
is same waveform
COM3 / COM0
is same waveform
When 1/1duty (Static)
COM1 ：same waveform as COM0
COM2 ：same waveform as COM0
COM3 ：same waveform as COM0
1/1Duty (Static)
Line inversion
Frame inversion
1frame
1frame
COM0
COM0
COM1
COM1
COM2
COM2
COM3
COM3
SEGn
SEGn
SEGn+1
SEGn+1
SEGn+2
SEGn+2
SEGn+3
SEGn+3
stateA
stateA
stateB
stateB
COM2
COM3
stateB
stateB
COM1
SEGn+2
SEGn+3
COM0
stateA
SEGn
SEGn+1
SEGn+2
SEGn+3
COM3
stateA
SEGn
SEGn+1
COM0
COM1
COM2
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TSZ22111･15･001
BU97941FV MAX 104 segments (SEG26×COM4)
●Initialization Sequence
Execute the following sequence after power supply and start display after the IC has initialized.
Power supply
↓
CSB „H‟ …Initialize I/F
↓
CSB „L‟ …Start I/F Data Transfer
↓
Execute Software Reset from SWRST command
↓
MODESET (Display off)
↓
Various command setting
↓
RAM WRITE
↓
MODESET (Display on)
↓
Start display
＊After inserting power supply, each register value, DDRAM address and DDRAM data are random prior to initialization.
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TSZ22111･15･001
BU97941FV MAX 104 segments (SEG26×COM4)
●Caution during Power supply ON/OFF
○POR circuit
During power supply rise, because the IC internal circuit and reset pass through an area of unstable low voltage and VDD
starts up, there is a risk that the inside of the IC is not completely reset and wrong operation might occur. In order to
prevent this, P.O.R circuit and Software Reset functions are incorporated. In order to ensure that operation, do as follows
during power supply rise:
1. Set power up conditions to meet the recommended tR, tOFF and Vbot specs below in order to ensure POR operation.
（POR circuit uses VDET type）
(＊The voltage detection of POR differs depending on the used environment etc.
In order to to assure the operation of POR, it is recommended to make Vbot = 0.5V or lower.)
Figure 15. Rise Waveform
2. When the conditions are not met, do the following countermeasures after power supply ON:
(1) Set CSB to ‟H‟.
(2) Turn ON the CSB and execute SWRST command.
In order for the SWRST command to take effect for sure, it is recommended to start up CSB after 1ms after the VDD
level has reached 90%.
※Since the state is irregular until SWRST command input after power supply ON, countermeasure through Software
Reset is not the perfect substitute for P.O.R function so it is important to be careful.
Figure 16. SWRST command sequence
VDD
CSB
Min 1ms
Min 50ns
SWRST command
Recommended conditions of tR, tOFF, Vbot
tR
tOFF
Vbot
VDET
10ms or lower
1ms or higher
0.5V or lower
TYP 1.2
V
VDD
tR
tOFF
Vbot
* VDET is integrated POR detection level
VDET
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TSZ22111･15･001
BU97941FV MAX 104 segments (SEG26×COM4)
●Power ON / OFF Sequence
To prevent incorrect display, malfunction and abnormal current,
VDD must be turned on before VLCD In power up sequence.
VDD must be turned off after VLCD In power down sequence.
Please satisfies VLCD≥VDD, t1>0ns, t2>0ns
MODE SET
Display off
SWRST
Various Setup
Blink RAM
WRITE
MODE SET
Display off
VDD min
VDD min
10%
10%
t1
t2
Command
VDD
VLCD
MODE SET
RAM WRITE
Figure 17. Power On/Off Sequence
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TSZ22111･15･001
BU97941FV MAX 104 segments (SEG26×COM4)
●Attention about using LEDCTL(85h) command
Please input CSB="H" after LEDCTL command is issued. To avoid noise and reset interface.
Figure 18. Recommended sequence when using LEDCTL (85h) command
●Attention about input port pull down
Satisfy the following sequence if input terminals are pulled down by external resistors (In case MPU output Hi-Z).
Figure 19. Recommended sequence when input ports are pulled down
BU97941FV adopts a 5V tolerant I/O for the digital input. This circuit includes a bus-hold function to keep the level of HIGH.
A pull down resistor of below 10KΩshall be connected to the input terminals to transit from HIGH to LOW because the
bus-hold transistor turns on during the input‟s HIGH level. (Refer to the Figure 5. I/O Equivalent Circuit)
A higher resistor than 10KΩ (approximate) causes input terminals being steady by intermediate potential between HIGH and
LOW level so unexpected current is consumed by the system.
The potential depends on the pull down resistance and bus-hold transistor‟s resistance.
As the bus-hold transistor turns off upon the input level cleared to LOW a higher resistor can be used as a pull down resistor
if an MPU sets SD and SCL lines to LOW before it releases the lines.
The LOW period preceding the MPU‟s bus release shall be at least 50ns as same as a minimum CLK width ( tSLW ).
0
D/C
0
0
1
P0
D6
D6
D5
D4
D3
D1
D0
D/C
0
P3
P2
P1
SCL
CSB
SD
1
2nd Command
1
LEDCTL (85h)
0
0
0
0
D2
0
Parameter
SCL
SD
CSB
Date transaction period with MPU
Input "L"
period
Input"Hi-Z"
period
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TSZ22111･15･001
BU97941FV MAX 104 segments (SEG26×COM4)
●Operational Notes
(1) Absolute maximum ratings
Operating the IC over the absolute maximum ratings may damage the IC. The damage can either be a short circuit
between pins or an open circuit between pins. Therefore, it is important to consider circuit protection measures, such as
adding a fuse, in case the IC is operated over the absolute maximum ratings.
(2) Recommended operating conditions
These conditions represent a range within which the expected characteristics of the IC can be approximately obtained.
The electrical characteristics are guaranteed under the conditions of each parameter.
(3) Reverse connection of power supply
Connecting the power supply in reverse polarity can damage the IC. Take precautions against reverse polarity when
connecting the power supply, such as mounting an external diode between the power supply and the IC‟s power supply
terminals.
(4) Power supply lines
Design the PCB layout pattern to provide low impedance ground and supply lines. Separate the ground and supply lines
of the digital and analog blocks to prevent noise in the ground and supply lines of the digital block from affecting the
analog block. Furthermore, connect a capacitor to ground at all power supply pins. Consider the effect of temperature
and aging on the capacitance value when using electrolytic capacitors.
(5) Ground Voltage
The voltage of the ground pin must be the lowest voltage of all pins of the IC at all operating conditions. Ensure that no
pins are at a voltage below the ground pin at any time, even during transient condition.
(6) Short between pins and mounting errors
Be careful when mounting the IC on printed circuit boards. The IC may be damaged if it is mounted in a wrong orientation
or if pins are shorted together. Short circuit may be caused by conductive particles caught between the pins.
(7) Operation under strong electromagnetic field
Operating the IC in the presence of a strong electromagnetic field may cause the IC to malfunction.
(8) Testing on application boards
When testing the IC on an application board, connecting a capacitor directly to a low-impedance output pin may subject
the IC to stress. Always discharge capacitors completely after each process or step. The IC‟s power supply should
always be turned off completely before connecting or removing it from the test setup during the inspection process. To
prevent damage from static discharge, ground the IC during assembly and use similar precautions during transport and
storage.
(9) Regarding input pins of the IC
In the construction of this IC, P-N junctions are inevitably formed creating parasitic diodes or transistors. The operation of
these parasitic elements can result in mutual interference among circuits, operational faults, or physical damage.
Therefore, conditions which cause these parasitic elements to operate, such as applying a voltage to an input pin lower
than the GND voltage should be avoided. Furthermore, do not apply a voltage to the input terminals when no power
supply voltage is applied to the IC. Even if the power supply voltage is applied, make sure that the input terminals have
voltages within the values specified in the electrical characteristics of this IC.
(10) GND wiring pattern
When using both small-signal and large-current GND traces, the two ground traces should be routed separately but
connected to a single ground at the reference point of the application board to avoid fluctuations in the small-signal
ground caused by large currents. Also ensure that the GND traces of external components do not cause variations on the
GND voltage. The power supply and ground lines must be as short and thick as possible to reduce line impedance.
(11) External Capacitor
When using a ceramic capacitor, determine the dielectric constant considering the change of capacitance with
temperature and the decrease in nominal capacitance due to DC bias and others.
(12) Unused input terminals
Input terminals of an IC are often connected to the gate of a CMOS transistor. The gate has extremely high impedance
and extremely low capacitance. If left unconnected, the electric field from the outside can easily charge it. The small
charge acquired in this way is enough to produce a significant effect on the conduction through the transistor and cause
unexpected operation of IC. So unless otherwise specified, input terminals not being used should be connected to the
power supply or ground line.
(13) Rush current
When power is first supplied to the IC, rush current may flow instantaneously. It is possible that the charge current to the
parasitic capacitance of internal photo diode or the internal logic may be unstable. Therefore, give special consideration
to power coupling capacitance, power wiring, width of GND wiring, and routing of connections.
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TSZ22111･15･001
BU97941FV MAX 104 segments (SEG26×COM4)
●Ordering Information
B
U
9
7
9
4
1
F
V
-
E 2
Part Number
Package
Packaging and forming specification
E2: Embossed tape and reel
(SSOP-B40)
FV
: SSOP-B40
●Marking Diagram
SSOP-B40(TOP VIEW)
B U 9 7 9 4 1
Part Number Marking
LOT Number
1PIN MARK
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TSZ22111･15･001
BU97941FV MAX 104 segments (SEG26×COM4)
●Physical Dimension, Tape and Reel Information
Package Name
SSOP-B40
(Max 13.95 (include. BURR)
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TSZ22111･15･001
BU97941FV MAX 104 segments (SEG26×COM4)
●Revision History
Date
Revision
Changes
14.Mar.2012
001
New Release
8.Jan.2013
002
Improved the statement in all pages.
Deleted “Status of this document” in page 20.
Changed format of Physical Dimension, Tape and Reel Information
26.Jan.2015
003
Add the condition when power supply in page 18.
10.Apr.2015
004
Modified figure of Power On/Off Sequence in page 18.
Datasheet
Datasheet
Notice-PGA-E Rev.001
© 2015 ROHM Co., Ltd. All rights reserved.
Notice
Precaution on using ROHM Products
1. Our Products are designed and manufactured for applicatio n in ordinar y elec tronic eq uipm ents (such as AV equipment ,
OA equipment, telecommunication equipment, home electronic appliances, amusement equipment, etc.). If you
intend to use our Products in devices requiring extremely high reliability (such as medical equipment (Not e 1), transport
equipment, traffic equipment, aircraft/spacecraft, nuclear power controllers, fuel controllers, car equipment including car
accessories, safety devices, etc.) and whose malfunction or failure may cause loss of human life, bodily injury or
serious damage to property (“Specific Applications”), please consult with the ROHM sales representative in advance.
Unless otherwise agreed in writing by ROHM in advance, ROHM shall not be in any way responsible or liable for any
damages, expenses or losses incurred b y you or third parties arisin g from the use of an y ROHM’s Prod ucts for Specific
Applications.
(Note1) Medical Equipment Classification of the Specific Applications
JAPAN USA EU CHINA
CLASSⅢ CLASSⅢ CLASSⅡb CLASSⅢ
CLASSⅣ CLASSⅢ
2. ROHM designs and manufactures its Products subject to strict quality control system. However, semiconductor
products can fail or malfunction at a certain rate. Please be sure to implement, at your own responsibilities, adequate
safety measures including but not limited to fail-safe d esign against the physical injur y, damage to any property, which
a failure or malfunction of our Products may cause. T he following are examples of safety measures:
[a] Installation of protection circuits or other protective devices to improve system safety
[b] Installation of redundant circuits to reduce the impact of single or multiple circuit failure
3. Our Products are designed and manufactured for use under standard conditions and not under any special or
extraordinary environments or conditions, as exemplified below. Accordingly, ROHM shall not be in any way
responsible or liable for any damages, expenses or losses arising from the use of any ROHM’s Products under any
special or extraordinary environments or conditions. If you intend to use our Products under any special or
extraordinary environments or conditions (as exemplified below), your independent verification and confirmation of
product performance, reliabili ty, etc, prior to use, must be necessary:
[a] Use of our Products in any types of liquid, including water, oils, chemicals, and organic solvents
[b] Use of our Products outdoors or in places where the Products are exposed to direct sunlig ht or dust
[c] Use of our Products in places where the Products are exposed to sea wind or corrosive gases, including Cl2,
H2S, NH3, SO2, and NO2
[d] Use of our Products in places where the Products are exposed to static electricity or electromagnetic waves
[e] Use of our Products in proximity to heat-producing comp onents, plastic cords, or other flammable items
[f] Sealing or coating our Products with resin or other coating materials
[g] Use of our Products without cleaning residue of flu x (even if you use no-clean type fluxes, cleaning residue of
flux is recommended); or Washing our Products by using water or water-soluble cleaning agents for cleaning
residue after soldering
[h] Use of the Products in places subject to dew condensation
4. The Products are not subject to radi ation-proof design.
5. Please verify and confirm ch aracteristics of the final or mounted products in using the Products.
6. In particular, if a transient load (a large amount of load applied in a short period of time, such as pulse. is applied,
confirmation of performance characteristics after on-board mounting is strongly recommended. Avoid applying power
exceeding normal rated power; exceeding the power rating under steady-state loading condition may negatively affect
product performance and reliability.
7. De-rate Power Dissipation (Pd ) dependi ng on Ambient temp erature (T a). When used i n sealed area, co nfirm the actual
ambient temperature.
8. Confirm that operation temperature is within the specified range described in the product specification.
9. ROHM shall n ot be in any way responsible or liable for failure induce d under deviant condition from what is defined in
this document.
Precaution for Mounting / Circuit board design
1. When a highly active halogen ous (chlori ne, bromine, etc.) flu x is used, the residue of flux may negativel y affect product
performance and reliability.
2. In principle, the reflow soldering method must be used on a surface-mount products, the flow soldering method must
be used on a through hole mount products. If the flow soldering method is preferred on a surface-mount products,
please consult with the ROHM represe ntative in advance.
For details, please refer to ROHM Mounting specification
Datasheet
Datasheet
Notice-PGA-E Rev.001
© 2015 ROHM Co., Ltd. All rights reserved.
Precautions Regarding Application Examples and External Circuits
1. If change is made to the constant of an external circuit, please allow a sufficient margin considering variations of the
characteristics of the Products and external components, including transient characteristics, as well as static
characteristics.
2. You agree that application notes, reference designs, and associated data and information contained in this document
are presented only as guidance for Products use. Therefore, in case you use such information, you are solely
responsible for it and you must exercise you r own indepen dent verificatio n and judgmen t in the use of such information
contained in this document. ROHM shall not be in any way responsible or liable for any damages, expenses or losses
incurred by you or third parties arising from the use of such information.
Precaution for Electrostatic
This Product is electrostatic sensitive product, which may be damaged due to electrostatic discharge. Please take proper
caution in your manufacturing process and storage so that voltage exceeding the Products maximum rating will not be
applied to Products. Please t ake special care under dry condit ion (e.g. Grounding of human body / equipment / sol der iron,
isolation from charged objects, setting of Ionizer, friction prevention and temperature / humidity control).
Precaution for Storage / Transportati on
1. Product performance and soldered connections may deteriorate if the Products are stored in the places where:
[a] the Products are exposed to sea winds or corrosive gases, including Cl2, H2S, NH3, SO2, and NO2
[b] the temperature or humidity exceeds those recommende d b y ROHM
[c] the Products are exposed to direct sunshine or condensation
[d] the Products are exposed to high Electrostatic
2. Even under ROHM recommended storage condition, solderabilit y of products out of recommended storage time period
may be degraded. It is strongly recommended to confirm solderability before using Products of which storage time is
exceeding the recommen de d storage time period.
3. Store / transport cartons in the correct direction, which is indicated on a carton with a symbol. Otherwise bent leads
may occur due to excessive s t ress applied when dropping o f a carton.
4. Use Products within the specified time after opening a humidity barrier bag. Baking is r equired before using Products of
which storage time is exceeding the recommended storage time period.
Precaution for Product Label
QR code printed on ROHM Products label is for ROHM’s internal use only.
Precaution for Disposition
When disposing Products pl ease dispose them properly using an authorized industry waste company.
Precaution for Foreign Exchange and Foreign Trade act
Since concerned goods might be fallen under listed items of export control prescribed by Foreign exchange and Foreign
trade act, please consult with ROHM in case of export.
Precaution Regarding Intellectual Property Rights
1. All information and data including but not limited to application example contained in this document is for reference
only. ROHM does not warrant that foregoi ng information or data will not infringe any int ellectual property rights or any
other rights of any third party regarding such information or data.
2. ROHM shall not have any obligations where the claims, actions or demands arising from the combination of the
Products with other articles such as components, circuits, systems or external equipment (including software).
3. No license, expressly or implied, is granted hereby under any intellectual property rights or other rights of ROHM or any
third parties with respect to the Products or the information contained i n this document. Provide d, however, that ROHM
will not assert its intellectual property rights or other rights against you or your customers to the extent necessary to
manufacture or sell products containing the Products, subject to the terms and conditions herein.
Other Precaution
1. This document may not be reprinted or reproduced, in whole or in part, without prior written consent of ROHM.
2. The Products may not be disassembled, converted, modified, reproduced or otherwise changed without prior written
consent of ROHM.
3. In no event shall you use in any way whatsoever the Products and the related technical information contained in the
Products or this document for any military purposes, including b ut not limited to, the development of mass-destruction
weapons.
4. The proper names of companies or products described in this document are trademarks or registered trademarks of
ROHM, its affiliated companies or third parties.
DatasheetDatasheet
Notice – WE Rev.001
© 2015 ROHM Co., Ltd. All rights reserved.
General Precaution
1. Before you use our Pro ducts, you are requested to care fully read this document and fully understand its contents.
ROHM shall n ot be in an y way responsible or liabl e for fa ilure, malfunction or acci dent arising from the use of a ny
ROHM’s Products against warning, caution or note contained in this document.
2. All information contained in this docume nt is current as of the issuing date and subj ect to change without any prior
notice. Before purchasing or using ROHM’s Products, please confirm the la test information with a ROHM sale s
representative.
3. The information contained in this doc ument is provi ded on an “as is” basis and ROHM does not warrant that all
information contained in this document is accurate an d/or error-free. ROHM shall not be in an y way responsible or
liable for an y damages, expenses or losses incurred by you or third parties resulting from inaccur acy or errors of or
concerning such information.
