IS31FL3733
12×16 DOTS MATRIX LED DRIVER
WITH INDIVIDUAL AUTO BREATH FUNCTION
August 2022
GENERAL DESCRIPTION
FEATURES
The IS31FL3733 is a general purpose 12×16 LEDs
matrix driver with 1/12 cycle rate. The device can be
programmed via an I2C compatible interface. Each
LED can be dimmed individually with 8-bit PWM data
which allowing 256 steps of linear dimming.
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IS31FL3733 features 3 Auto Breathing Modes which
are noted as ABM-1, ABM-2 and ABM-3. For each
Auto Breathing Mode, there are 4 timing characters
which include current rising / holding / falling / off time
and 3 loop characters which include Loop-Beginning /
Loop-Ending / Loop-Times. Every LED can be
configured to be any Auto Breathing Mode or NoBreathing Mode individually.
Additionally each LED open and short state can be
detected, IS31FL3733 store the open or short
information in Open-Short Registers. The Open-Short
Registers allowing MCU to read out via I2C
compatible interface. Inform MCU whether there are
LEDs open or short and the locations of open or short
LEDs.
The IS31FL3733 operates from 2.7V to 5.5V and
features a very low shutdown and operational current.
IS31FL3733 is available in QFN-48 (6mm×6mm) and
eTQFP-48 packages. It operates from 2.7V to 5.5V
over the temperature range of -40°C to +125°C.
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•
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•
Supply voltage range: 2.7V to 5.5V
16 current source outputs for row control
12 switch current inputs for column scan control
Up to 192 LEDs (12×16) in dot matrix
Programmable 12×16 (64 RGBs) matrix size with
de-ghost function
1MHz I2C-compatible interface
Selectable 3 Auto Breath Modes for each dot
Auto Breath Loop Features interrupt pin inform
MCU Auto Breath Loop completed
Auto Breath offers 128 steps gamma current,
interrupt and state look up registers
256 steps Global Current Setting
Individual on/off control
Individual 256 PWM control steps
Individual Auto Breath Mode select
Individual open and short error detect function
Cascade for synchronization of chips
QFN-48 (6mm×6mm) and eTQFP-48 packages
APPLICATIONS
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•
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Hand-held devices for LED display
Gaming device (Keyboard, Mouse etc.)
LED in white goods application
TYPICAL APPLICATION CIRCUIT
Figure 1 Typical Application Circuit (12×16)
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Rev. F, 08/01/2022
1
IS31FL3733
TYPICAL APPLICATION CIRCUIT (CONTINUED)
*Note 2
VBattery
22 F/10V
20
0.47 F 0.1 F
0.47 F 0.1 F
0.47 F 0.1 F
29
VIO
PVCC
VIO/MCU
39
0.47 F
PVCC
37
AVCC
38
DVCC
CS1 CS2 CS3 CS4 CS5 CS6 CS7 CS8 CS9 CS10 CS11 CS12 CS13 CS14 CS15 CS16
CS16
CS15
33
32
2k
K
SW11
VIO/MCU
100k
L
SW12
2k
41
42
45
Micro
Controller
46
47
100k 100k
CS2
SDA
SCL
INTB
CS1
17
16
IS31FL3733
J
SW10
I
SW9
H
SW8
SDB
SW12
IICRST
SW11
15
14
G
SW7
F
SW6
E
SW5
40
35
43
REXT
20k
44
48
SYNC
R_EXT
SW2
SW1
ADDR1
ADDR2
PGND
GND
AGND
3
2
5,12
34
D
SW4
C
SW3
B
SW2
A
SW1
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Figure 2 Typical Application Circuit (RGB)
Figure 3 Typical Application Circuit (Eight Parts Synchronization-Work)
Note 1: IC should be placed far away from the antenna in order to prevent the EMI.
Note 2: Electrolytic/Tantalum Capacitor maybe considered for high current application to avoid audible noise interference.
Note 3: The VIO should be 1.8V≤ VIO ≤VCC. And it is recommended to be equal to VOH of the micro controller. For example, if VOH=1.8V, set
VIO=1.8V, if VOH=3.3V, set VIO=3.3V.
Note 4: One system should contain only one master, all slave parts should be configured as slave mode before the master is configured as
master mode. Work as master mode or slave mode specified by Configuration Register (Function Register, address 00h). Master part output
master clock, and all the other parts which work as slave input this master clock.
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2
IS31FL3733
PIN CONFIGURATION
Package
Pin Configuration (Top View)
NC 1
QFN-48
36 NC
SW1 2
35 R_EXT
SW2 3
34 AGND
SW3 4
33 CS16
PGND 5
32 CS15
SW4 6
31 CS14
SW5 7
30 CS13
SW6 8
29 PVCC
SW7 9
28 CS12
SW8 10
27 CS11
SW9 11
26 CS10
PGND 12
37 AVCC
41 SDA
PVCC 20
CS8 24
42 SCL
CS4 19
38 DVCC
43 ADDR1
CS3 18
CS7 23
44 ADDR2
CS2 17
39 VIO
45 INTB
CS1 16
CS6 22
46 SDB
SW12 15
40 SYNC
47 IICRST
SW11 14
CS5 21
48 GND
SW10 13
25 CS9
eTQFP-48
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3
IS31FL3733
PIN DESCRIPTION
No.
Pin
Description
1,36
NC
Not connect.
2~4,6~11,
13~15
SW1~SW12
Switch pin for LED matrix scanning.
5,12
PGND
Power GND.
16~19, 21~28,
30~33
CS1~CS16
Current Source.
20, 29
PVCC
Power for current source.
34
AGND
Analog GND.
35
R_EXT
Input terminal used to connect an external resistor.
This regulates current source DC current value.
37
AVCC
Power for analog circuits.
38
DVCC
Power for digital circuits.
39
VIO
Input logic reference voltage.
40
SYNC
Synchronize pin. It is used for more than one part
work synchronize. If it is not used please float this pin.
41
SDA
I2C compatible serial data.
42
SCL
I2C compatible serial clock.
43
ADDR1
I2C address setting.
44
ADDR2
I2C address setting.
45
INTB
Interrupt output pin. Register F0h sets the function of
the INTB pin and active low when the interrupt event
happens. Can be NC (float) if interrupt function no
used.
46
SDB
Shutdown the chip when pull to low.
47
IICRST
Reset I2C when pull high, need to pull down when
normal operation.
48
GND
Connect to GND.
Thermal Pad
Need to connect to GND pins.
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4
IS31FL3733
ORDERING INFORMATION
Industrial Range: -40°C to +125°C
Order Part No.
Package
QTY
IS31FL3733-QFLS4-TR
IS31FL3733-TQLS4
QFN-48, Lead-free
eTQFP-48, Lead-free
2500/Reel
250/Tray
Copyright © 2022 Lumissil Microsystems. All rights reserved. Lumissil Microsystems reserves the right to make changes to this specification and its
products at any time without notice. Lumissil Microsystems assumes no liability arising out of the application or use of any information, products or
services described herein. Customers are advised to obtain the latest version of this device specification before relying on any published information and
before placing orders for products.
Lumissil Microsystems does not recommend the use of any of its products in life support applications where the failure or malfunction of the product can
reasonably be expected to cause failure of the life support system or to significantly affect its safety or effectiveness. Products are not authorized for use
in such applications unless Lumissil Microsystems receives written assurance to its satisfaction, that:
a.) the risk of injury or damage has been minimized;
b.) the user assume all such risks; and
c.) potential liability of Lumissil Microsystems is adequately protected under the circumstances
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Rev. F, 08/01/2022
5
IS31FL3733
ABSOLUTE MAXIMUM RATINGS
Supply voltage, VCC
Voltage at any input pin
Maximum junction temperature, TJMAX
Storage temperature range, TSTG
Operating temperature range, TA=TJ
Package thermal resistance, junction to ambient (4-layer standard test PCB based
on JESD 51-2A standard), θJA
ESD (HBM)
ESD (CDM)
-0.3V ~ +6.0V
-0.3V ~ VCC+0.3V
+150°C
-65°C ~ +150°C
-40°C ~ +125°C
37.5°C/W (QFN)
39.0°C/W (eTQFP)
±8kV
±1kV
Note 5: Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress
ratings only and functional operation of the device at these or any other condition beyond those indicated in the operational sections of the
specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
The following specifications apply for VCC= 3.6V, TA= 25°C, unless otherwise noted.
Symbol
VCC
Parameter
Supply voltage
ICC
Quiescent power supply current
ISD
Shutdown current
IOUT
ILED
Conditions
Min.
Typ.
2.7
Max.
Unit
5.5
V
VSDB= VCC, all LEDs off
2
3
VSDB= VCC, all LEDs off,
GCC= 0x12
2
3
VSDB= 0V
2
5
VSDB= VCC, Configuration Register
written “0000 0000
2
5
mA
μA
REXT= 20kΩ, GCC= 255,
PWM= 255
38
42
46
mA
REXT= 20kΩ, GCC= 0x12,
PWM= 255
2.66
2.95
3.25
mA
Average current on each LED
ILED= IOUT/12.75
REXT= 20kΩ, GCC= 255,
PWM= 255
3.05
3.29
3.61
mA
Current sink headroom voltage
SW1~SW12
ISINK= 672mA (Note 6, 7)
300
400
Maximum constant current of
CS1~CS16
VHR
Current source headroom
voltage CS1~C16
ISINK= 48mA, GCC= 0x12
100
ISOURCE= 42mA (Note 6)
150
ISOURC = 3mA, GCC= 0x12
200
mV
100
tSCAN
Period of scanning
115
128
140
µs
tNOL
Non-overlap blanking time
during scan, the SWy and CSx
are all off during this time
7.2
8
8.75
µs
Logic Electrical Characteristics (SDA, SCL, ADDR1, ADDR2, SYNC, SDB)
VIL
Logic “0” input voltage
VIO= 3.6V
GND
0.2VIO
V
VIH
Logic “1” input voltage
VIO= 3.6V
0.75VIO
VIO
V
VHYS
Input Schmitt trigger hysteresis
VIO= 3.6V
VOL
Logic “0” output voltage for
IOL= 8mA
SYNC
VOH
Logic “1” output voltage for
IOH= 8mA
SYNC
0.2
V
0.4
0.75VIO
V
V
IIL
Logic “0” input current
VINPUT= 0V (Note 8)
5
nA
IIH
Logic “1” input current
VINPUT= VIO (Note 8)
5
nA
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6
IS31FL3733
DIGITAL INPUT SWITCHING CHARACTERISTICS (NOTE 8)
Symbol
Parameter
fSCL
Serial-clock frequency
tBUF
Fast Mode
Min.
Typ.
Fast Mode Plus
Max. Min.
Typ.
Max.
Units
-
400
-
1000
kHz
Bus free time between a STOP and a START
condition
1.3
-
0.5
-
μs
tHD, STA
Hold time (repeated) START condition
0.6
-
0.26
-
μs
tSU, STA
Repeated START condition setup time
0.6
-
0.26
-
μs
tSU, STO
STOP condition setup time
0.6
-
0.26
-
μs
tHD, DAT
Data hold time
-
-
-
-
μs
tSU, DAT
Data setup time
100
-
50
-
ns
tLOW
SCL clock low period
1.3
-
0.5
-
μs
tHIGH
SCL clock high period
0.7
-
0.26
-
μs
tR
Rise time of both SDA and SCL signals,
receiving
-
300
-
120
ns
tF
Fall time of both SDA and SCL signals,
receiving
-
300
-
120
ns
Note 6: In case of REXT = 20kΩ, Global Current Control Register (PG3, 01h) written “1111 1111”, GCC = “1111 1111”.
Note 7: All LEDs are on and PWM = “1111 1111”, GCC = “1111 1111”.
Note 8: Guaranteed by design.
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7
IS31FL3733
FUNCTIONAL BLOCK DIAGRAM
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Rev. F, 08/01/2022
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IS31FL3733
DETAILED DESCRIPTION
I2C INTERFACE
The IS31FL3733 uses a serial bus, which conforms to
the I2C protocol, to control the chip’s functions with
two wires: SCL and SDA. The IS31FL3733 has a 7-bit
slave address (A7:A1), followed by the R/W bit, A0.
Set A0 to “0” for a write command and set A0 to “1” for
a read command. The value of bits A1 and A2 are
decided by the connection of the ADDR1 pin. The
value of bits A3 and A4 are decided by the connection
of the ADDR2 pin.
The complete slave address is:
Table 1 Slave Address:
ADDR2 ADDR1
GND
GND
GND
GND
SCL
SCL
SCL
SCL
SDA
SDA
SDA
SDA
VCC
VCC
VCC
VCC
GND
SCL
SDA
VCC
GND
SCL
SDA
VCC
GND
SCL
SDA
VCC
GND
SCL
SDA
VCC
A7:A5
A4:A3
A2:A1
101
00
00
00
00
01
01
01
01
10
10
10
10
11
11
11
11
00
01
10
11
00
01
10
11
00
01
10
11
00
01
10
11
A0
After the last bit of the chip address is sent, the
master checks for the IS31FL3733’s acknowledge.
The master releases the SDA line high (through a
pull-up resistor). Then the master sends an SCL pulse.
If the IS31FL3733 has received the address correctly,
then it holds the SDA line low during the SCL pulse. If
the SDA line is not low, then the master should send a
“STOP” signal (discussed later) and abort the transfer.
Following acknowledge of IS31FL3733, the register
address byte is sent, most significant bit first.
IS31FL3733 must generate another acknowledge
indicating that the register address has been received.
Then 8-bit of data byte are sent next, most significant
bit first. Each data bit should be valid while the SCL
level is stable high. After the data byte is sent, the
IS31FL3733 must generate another acknowledge to
indicate that the data was received.
0/1
ADDR1/2 connected to GND, (A2:A1)/(A4:A3)=00;
ADDR1/2 connected to VCC, (A2:A1)/(A4:A3)=11;
ADDR1/2 connected to SCL, (A2:A1)/(A4:A3)=01;
ADDR1/2 connected to SDA, (A2:A1)/(A4:A3)=10;
The SCL line is uni-directional. The SDA line is bidirectional (open-collector) with a pull-up resistor
(typically 1kΩ). The maximum clock frequency
specified by the I2C standard is 1MHz. In this
discussion, the master is the microcontroller and the
slave is the IS31FL3733.
The timing diagram for the I2C is shown in Figure 4.
The SDA is latched in on the stable high level of the
SCL. When there is no interface activity, the SDA line
should be held high.
The “START” signal is generated by lowering the SDA
signal while the SCL signal is high. The start signal will
alert all devices attached to the I2C bus to check the
incoming address against their own chip address.
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Rev. F, 08/01/2022
The 8-bit chip address is sent next, most significant bit
first. Each address bit must be stable while the SCL
level is high.
The “STOP” signal ends the transfer. To signal
“STOP”, the SDA signal goes high while the SCL
signal is high.
ADDRESS AUTO INCREMENT
To write multiple bytes of data into IS31FL3733, load
the address of the data register that the first data byte
is intended for. During the IS31FL3733 acknowledge
of receiving the data byte, the internal address pointer
will increment by one. The next data byte sent to
IS31FL3733 will be placed in the new address, and so
on. The auto increment of the address will continue as
long as data continues to be written to IS31FL3733
(Figure 7).
READING OPERATION
Register FEh, F1h, 18h~45h of Page 0 and 11h of
Page 3 can be read.
To read the FEh and F1h, after I2C start condition, the
bus master must send the IS31FL3733 device
____
address with the R/W bit set to “0”, followed by the
register address (FEh or F1h) which determines which
register is accessed. Then restart I2C, the bus master
should send the IS31FL3733 device address with the
____
R/W bit set to “1”. Data from the register defined by
the command byte is then sent from the IS31FL3733
to the master (Figure 8).
To read the 18h~45h of Page 0 and 11h of Page 3,
the FDh should write with 00h before follow the Figure
8 sequence to read the data, that means, when you
want to read 18h~45h of Page 0 and 11h of Page 3
the FDh should point to Page 0 first and you can read
the Page 0 data.
9
IS31FL3733
Figure 4 Interface Timing
Figure 5 Bit Transfer
Figure 6 Writing to IS31FL3733 (Typical)
Figure 7 Writing to IS31FL3733 (Automatic Address Increment)
Figure 8 Reading from IS31FL3733
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Rev. F, 08/01/2022
10
IS31FL3733
REGISTER DEFINITION-1
Address
Name
Function
Table
R/W
Default
2
W
xxxx xxxx
FDh
Command Register
Available Page 0 to Page 3 Registers
FEh
Command Register Write lock To lock/unlock Command Register
3
R/W
F0h
Interrupt Mask Register
Configure the interrupt function
4
W
F1h
Interrupt Status Register
Show the interrupt status
5
R
0000 0000
REGISTER CONTROL
Table 2 FDh Command Register (Write Only)
Data
Function
0000 0000
Point to Page 0 (PG0, LED Control Register is available)
0000 0001
Point to Page 1 (PG1, PWM Register is available)
0000 0010
Point to Page 2 (PG2, Auto Breath Mode Register is available)
0000 0011
Point to Page 3 (PG3, Function Register is available)
Others
Reserved
Note: FDh is locked when power up, need to unlock this register before write command to it. See Table 3 for detail.
The Command Register should be configured first after writing in the slave address to choose the available register. Then write data in the
choosing register. Power up default state is “0000 0000”.
For example, when write “0000 0001” in the Command Register (FDh), the data which writing after will be stored in the PWM Register (Page1).
Write new data can configure other registers.
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11
IS31FL3733
Table 3 FEh Command Register Write Lock
(Read/Write)
Table 5 F1h Interrupt Status Register (Read Only)
Bit
D7:D0
Name
CRWL
Default
0000 0000 (FDh write disable)
Bit
D7:D5
Name
-
Default
000
D4
D3
D2
ABM3 ABM2 ABM1
0
0
0
D1
D0
SB
OB
0
0
Show the interrupt status for IC.
To select the PG0~PG3, need to unlock this register
first, with the purpose to avoid misoperation of this
register. When FEh is written with 0xC5, FDh is
allowed to modify once, after the FDh is modified the
FEh will reset to be 0x00 at once.
ABM3 Auto Breath Mode 3 Finish Bit
0
ABM3 not finish
1
ABM3 finish
ABM2 Auto Breath Mode 2 Finish Bit
0
ABM2 not finish
1
ABM2 finish
CRWL Command Register Write Lock
0x00 FDh write disable
0xC5 FDh write enable once
Table 4 F0h Interrupt Mask Register (Write Only)
Bit
D7:D4
D3
D2
D1
D0
Name
-
IAC
IAB
IS
IO
Default
0000
0
0
0
0
Configure the interrupt function for IC.
IAC
Auto Clear Interrupt Bit
0
Interrupt could not auto clear
1
Interrupt auto clear when INTB stay low
exceeds 8ms
IAB
0
1
Auto Breath Interrupt Bit
Disable auto breath loop finish interrupt
Enable auto breath loop finish interrupt
IS
0
1
Dot Short Interrupt Bit
Disable dot short interrupt
Enable dot short interrupt
IO
0
1
Dot Open Interrupt Bit
Disable dot open interrupt
Enable dot open interrupt
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ABM1 Auto Breath Mode 1 Finish Bit
0
ABM1 not finish
1
ABM1 finish
SB
0
1
Short Bit
No short
Short happens
OB
0
1
Open Bit
No open
Open happens
12
IS31FL3733
REGISTER DEFINITION-2
Address
Name
Function
Table
R/W
Default
PG0 (0x00): LED Control Register
00h ~ 17h LED On/Off Register
Set on or off state for each LED
7
W
18h ~ 2Fh LED Open Register
Store open state for each LED
8
R
30h ~ 47h LED Short Register
Store short state for each LED
9
R
Set PWM duty for LED
10
W
0000 0000
11
W
0000 0000
0000 0000
PG1 (0x01): PWM Register
00h~BFh
PWM Register
PG2 (0x02): Auto Breath Mode Register
00h~BFh
Auto Breath Mode Register Set operating mode of each dot
PG3 (0x03): Function Register
00h
Configuration Register
Configure the operation mode
13
W
01h
Global Current Control
Register
Set the global current
14
W
02h
Auto Breath Control
Register 1 of ABM-1
Set fade in and hold time for breath
function of ABM-1
15
W
03h
Auto Breath Control
Register 2 of ABM-1
Set the fade out and off time for breath
function of ABM-1
16
W
04h
Auto Breath Control
Register 3 of ABM-1
Set loop characters of ABM-1
17
W
05h
Auto Breath Control
Register 4 of ABM-1
Set loop characters of ABM-1
18
W
06h
Auto Breath Control
Register 1 of ABM-2
Set fade in and hold time for breath
function of ABM-2
15
W
07h
Auto Breath Control
Register 2 of ABM-2
Set the fade out and off time for breath
function of ABM-2
16
W
08h
Auto Breath Control
Register 3 of ABM-2
Set loop characters of ABM-2
17
W
09h
Auto Breath Control
Register 4 of ABM-2
Set loop characters of ABM-2
18
W
0Ah
Auto Breath Control
Register 1 of ABM-3
Set fade in and hold time for breath
function of ABM-3
15
W
0Bh
Auto Breath Control
Register 2 of ABM-3
Set the fade out and off time for breath
function of ABM-3
16
W
0Ch
Auto Breath Control
Register 3 of ABM-3
Set loop characters of ABM-3
17
W
0Dh
Auto Breath Control
Register 4 of ABM-3
Set loop characters of ABM-3
18
W
0Eh
Time Update Register
Update the setting of 02h ~ 0Dh registers
-
W
0Fh
SWy Pull-Up Resistor
Selection Register
Set the pull-up resistor for SWy
19
W
10h
CSx Pull-Down Resistor
Selection Register
Set the pull-down resistor for CSx
20
W
11h
Reset Register
Reset all register to POR state
-
R
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Rev. F, 08/01/2022
0000 0000
13
IS31FL3733
Table 6 Page 0 (PG0, 0x00): LED Control Register
LED Location
LED On/Off Register
LED Open Register LED Short Register
SW1(CS1~ CS8)
SW1(CS9~ CS16)
00h
01h
18h
19h
30h
31h
SW2(CS1~ CS8)
SW2(CS9~ CS16)
02h
03h
1Ah
1Bh
32h
33h
SW3(CS1~ CS8)
SW3(CS9~ CS16)
04h
05h
1Ch
1Dh
34h
35h
SW4(CS1~ CS8)
SW4(CS9~ CS16)
06h
07h
1Eh
1Fh
36h
37h
SW5(CS1~ CS8)
SW5(CS9~ CS16)
08h
09h
20h
21h
38h
39h
SW6(CS1~ CS8)
SW6(CS9~ CS16)
0Ah
0Bh
22h
23h
3Ah
3Bh
SW7(CS1~ CS8)
SW7(CS9~ CS16)
0Ch
0Dh
24h
25h
3Ch
3Dh
SW8(CS1~ CS8)
SW8(CS9~ CS16
0Eh
0Fh
26h
27h
3Eh
3Fh
SW9(CS1~ CS8)
SW9(CS9~ CS16)
10h
11h
28h
29h
40h
41h
SW10(CS1~ CS8)
SW10(CS9~ CS16)
12h
13h
2Ah
2Bh
42h
43h
SW11(CS1~ CS8)
SW11(CS9~ CS16)
14h
15h
2Ch
2Dh
44h
45h
SW12(CS1~ CS8)
SW12(CS9~ CS16)
16h
17h
2Eh
2Fh
46h
47h
Table 7 00h ~ 17h LED On/Off Register
Table 9 30h ~ 47h LED Short Register
Bit
D7:D0
Bit
D7:D0
Name
CCS8 : CCS1 or CCS16 : CCS9
Name
ST8 : ST1 or ST16 : ST9
Default
0000 0000
Default
0000 0000
The LED On/Off Registers store the on or off state of
each LED in the Matrix.
The LED Short Registers store the short or normal
state of each LED in the Matrix.
CX-Y
0
1
STx
0
1
LED State Bit
LED off
LED on
LED Short Bit
LED normal
LED short
Table 8 18h ~ 2Fh LED Open Register
Bit
D7:D0
Name
OP8 : OP1 or OP16 : OP9
Default
0000 0000
The LED Open Registers store the open or normal
state of each LED in the Matrix.
OPx
0
1
LED Open Bit
LED normal
LED open
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Rev. F, 08/01/2022
14
IS31FL3733
Page 1 (PG1, 0x01): PWM Register
PVCC
PWM PWM PWM PWM PWM PWM PWM PWM PWM PWM PWM PWM PWM PWM PWM PWM
CS1 CS2 CS3 CS4 CS5 CS6 CS7 CS8 CS9
CS10 CS11 CS12 CS13 CS14 CS15 CS16
L
B0
B3 B4 B5 B6 B7 B8 B9 BA BB BC BD BE BF
SW12
K
A0 A1 A2 A3 A4 A5 A6 A7 A8 A9 AA AB AC AD AE AF
SW11
90
9F
SW10
8F
SW9
J
80
I
B1
91
81
B2
92
82
93
94
83
84
95
96
85
86
97
87
98
88
99
89
9A 9B 9C 9D 9E
8A 8B 8C 8D 8E
H
70
71
72
73
74
75
76
77
78
79
7A 7B 7C 7D 7E
7F
SW8
G
60
61
62
63
64
65
66
67
68
69
6A 6B 6C 6D 6E
6F
SW7
F
50
51
52
53
54
55
56
57
58
59
5A 5B 5C 5D 5E
5F
SW6
E
40
41
42
43
44
45
46
47
48
49
4A 4B 4C 4D 4E
4F
SW5
D
30
31
32
33
34
35
36
37
38
39
3A 3B 3C 3D 3E
3F
SW4
C
20
21
22
23
24
25
26
27
28
29
2A 2B 2C 2D 2E
2F
SW3
1F
SW2
SW1
10
B
A
11
12
13
14
15
16
17
18
19
1A 1B 1C 1D 1E
00
01
02
03
04
05
06
07
08
09
0A 0B 0C 0D 0E
0F
1
2
3
4
5
6
7
8
9
10
11
16
12
13
14
15
T12
T11
T10
T09
T08
T07
T06
T05
T04
T03
T02
T01
Figure 9 PWM Register
Table 10 00h ~ BFh PWM Register
Bit
D7:D0
Name
PWM
Default
0000 0000
Where Duty is the duty cycle of SWy,
Duty =
PWM
× I OUT × Duty
256
PWM =
(1)
IOUT =
n
n =0
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Rev. F, 08/01/2022
840 GCC
×
REXT 256
(3)
GCC is the Global Current Control register (PG3,
01h) value and REXT is the external resistor of
R_EXT pin. D[n] stands for the individual bit value, 1
or 0, in location n.
For example: if D7:D0= 10110101 (0xB5, 181),
GCC=255, REXT=20kΩ (IOUT=42mA),
7
D[n ] ⋅ 2
(2)
IOUT is the output current of CSx (x=1~16),
Each dot has a byte to modulate the PWM duty in
256 steps.
The value of the PWM Registers decides the
average current of each LED noted ILED.
ILED computed by Formula (1):
I LED =
128μs
1
1
× =
(128μs + 8μs) 12 12.75
I LED =
20 + 22 + 24 + 25 + 27
1
× I OUT ×
= 2 .34 mA
256
12 .75
15
IS31FL3733
Page 2 (PG2, 0x02): Auto Breath Mode Register
PVCC
PWM PWM PWM PWM PWM PWM PWM PWM PWM PWM PWM PWM PWM PWM PWM PWM
CS1 CS2 CS3 CS4 CS5 CS6 CS7 CS8 CS9
CS10 CS11 CS12 CS13 CS14 CS15 CS16
L
B0
B3 B4 B5 B6 B7 B8 B9 BA BB BC BD BE BF
SW12
K
A0 A1 A2 A3 A4 A5 A6 A7 A8 A9 AA AB AC AD AE AF
SW11
J
90
91
92
93
94
95
96
97
98
99
9A 9B 9C 9D 9E
9F
SW10
I
80
81
82
83
84
85
86
87
88
89
8A 8B 8C 8D 8E
8F
SW9
H
70
71
72
73
74
75
76
77
78
79
7A 7B 7C 7D 7E
7F
SW8
6F
SW7
5F
SW6
4F
SW5
60
G
50
F
40
E
B1
61
51
41
B2
62
52
42
63
53
43
64
54
44
65
55
45
66
67
56
57
46
47
68
58
48
69
59
49
6A 6B 6C 6D 6E
5A 5B 5C 5D 5E
4A 4B 4C 4D 4E
D
30
31
32
33
34
35
36
37
38
39
3A 3B 3C 3D 3E
3F
SW4
C
20
21
22
23
24
25
26
27
28
29
2A 2B 2C 2D 2E
2F
SW3
B
10
11
12
13
14
15
16
17
18
19
1A 1B 1C 1D 1E
1F
SW2
A
00
01
02
03
04
05
06
07
08
09
0A 0B 0C 0D 0E
0F
1
2
3
4
5
6
7
8
9
10
11
16
12
13
14
15
SW1
T12
T11
T10
T09
T08
T07
T06
T05
T04
T03
T02
T01
Figure 10 Auto Breath Mode Selection Register
Table 11 00h ~ BFh Auto Breath Mode Register
Bit
D7:D2
D1:D0
Name
-
ABMS
Default
-
00
The Auto Breath Mode Register sets operating mode
of each dot.
ABMS
00
01
10
11
Auto Breath Mode Selection Bit
PWM control mode
Select Auto Breath Mode 1 (ABM-1)
Select Auto Breath Mode 2 (ABM-2)
Select Auto Breath Mode 3 (ABM-3)
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Rev. F, 08/01/2022
16
IS31FL3733
Table 12 Page 3 (PG3, 0x03): Function Register
Register
Name
Function
R/W
00h
Configuration Register
Configure the operation mode
W
01h
Global Current Control
Register
Set the global current
W
02h
Auto Breath Control
Register 1 of ABM-1
Set fade in and hold time for breath function of
ABM-1
W
03h
Auto Breath Control
Register 2 of ABM-1
Set the fade out and off time for breath function
of ABM-1
W
04h
Auto Breath Control
Register 3 of ABM-1
Set loop characters of ABM-1
W
05h
Auto Breath Control
Register 4 of ABM-1
Set loop characters of ABM-1
W
06h
Auto Breath Control
Register 1 of ABM-2
Set fade in and hold time for breath function of
ABM-2
W
07h
Auto Breath Control
Register 2 of ABM-2
Set the fade out and off time for breath function
of ABM-2
W
08h
Auto Breath Control
Register 3 of ABM-2
Set loop characters of ABM-2
W
09h
Auto Breath Control
Register 4 of ABM-2
Set loop characters of ABM-2
W
0Ah
Auto Breath Control
Register 1 of ABM-3
Set fade in and hold time for breath function of
ABM-3
W
0Bh
Auto Breath Control
Register 2 of ABM-3
Set the fade out and off time for breath function
of ABM-3
W
0Ch
Auto Breath Control
Register 3 of ABM-3
Set loop characters of ABM-3
W
0Dh
Auto Breath Control
Register 4 of ABM-3
Set loop characters of ABM-3
W
0Eh
Time Update Register
Update the setting of 02h ~ 0Dh registers
W
0Fh
SWy Pull-Up Resistor
Selection Register
Set the pull-up resistor for Swy
W
10h
CSx Pull-Down Resistor
Selection Register
Set the pull-down resistor for CSx
W
11h
Reset Register
Reset all register to POR state
R
Table 13 00h Configuration Register
Bit
D7:D6
D5:D3
D2
D1
D0
Name
SYNC
-
OSD
B_EN
SSD
Default
00
000
0
0
0
The Configuration Register sets operating mode of
IS31FL3733.
When SYNC bits are set to “01”, the IS31FL3733 is
configured as the master clock source and the
SYNC pin will generate a clock signal distributed to
the clock slave devices. To be configured as a clock
slave device and accept an external clock input the
slave device’s SYNC bits must be set to “10”.
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Rev. F, 08/01/2022
Default
0000
0000
When OSD set high, open/short detection will be
trigger once, the user could trigger OS detection
again by set OSD from “0” to “1”.
When B_EN enable, those dots select working in
ABM-x mode will start to run the pre-established
timing. If it is disabled, all dots work in PWM mode.
Following Figure 16 to enable the Auto Breath mode
When SSD is “0”, IS31FL3733 works in software
shutdown mode and to normal operate the SSD bit
should set to “1”.
17
IS31FL3733
SYNC
00/11
01
10
Synchronize Configuration
High Impedance
Master
Slave
OSD
0
1
Open/Short Detection Enable Bit
Disable open/short detection
Enable open/short detection
B_EN Auto Breath Enable
0
PWM Mode Enable
1
Auto Breath Mode Enable
SSD
0
1
Software Shutdown Control
Software shutdown
Normal operation
011
100
101
110
111
1.68s
3.36s
6.72s
13.44s
26.88s
T2
0000
0001
0010
0011
0100
0101
0110
0111
1000
Others
T2 Setting
0s
0.21s
0.42s
0.84s
1.68s
3.36s
6.72s
13.44s
26.88s
Unavailable
Table 14 01h Global Current Control Register
Bit
D7:D0
Name
GCCx
Default
0000 0000
Table 16 03h, 07h, 0Bh Auto Breath Control
Register 2 of ABM-x
The Global Current Control Register modulates all
CSx (x=1~16) DC current which is noted as IOUT in
256 steps.
IOUT is computed by the Formula (3):
IOUT =
840 GCC
×
REXT 256
GCC =
(3)
7
D[ n ] ⋅ 2
n
n=0
Where D[n] stands for the individual bit value, 1 or 0,
in location n, REXT is the external resistor of R_EXT
pin.
For example: if D7:D0 = 1011 0101,
IOUT =
20 + 22 + 24 + 25 + 27 840
×
256
REXT
Table 15 02h, 06h, 0Ah Auto Breath Control
Register 1 of ABM-x
Bit
D7:D5
D4:D1
D0
Name
T1
T2
-
Default
000
0000
0
Auto Breath Control Register 1 set the T1&T2 time in
Auto Breath Mode.
T1
000
001
010
T1 Setting
0.21s
0.42s
0.84s
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Rev. F, 08/01/2022
Bit
D7:D5
D4:D1
D0
Name
T3
T4
-
Default
000
0000
0
Auto Breath Control Register 2 set the T3&T4 time in
Auto Breath Mode.
T3
000
001
010
011
100
101
110
111
T3 Setting
0.21s
0.42s
0.84s
1.68s
3.36s
6.72s
13.44s
26.88s
T4
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
Others
T4 Setting
0s
0.21s
0.42s
0.84s
1.68s
3.36s
6.72s
13.44s
26.88s
53.76s
107.52s
Unavailable
18
IS31FL3733
Table 17 04h, 08h, 0Ch Auto Breath Control
Register 3 of ABM-x
Table 18 05h, 09h, 0Dh Auto Breath Control
Register 4 of ABM-x
Bit
D7:D6
D5:D4
D3:D0
Bit
D7:D0
Name
LE
LB
LTA
Name
LTB
Default
00
00
0000
Default
0000 0000
Total loop times= LTA ×256 + LTB.
For example, if LTA=2, LTB=100, the total loop times
is 256×2+100= 612 times.
For the counting of breathing times, do follow Figure
16 to enable the Auto Breath Mode.
If the loop start from T4,
T4->T1->T2->T3(1)->T4->T1->T2->T3(2)->T4->T1>... and so on.
If the loop not start from T4,
Tx->T3(1) ->T4->T1->T2->T3(2)->T4-> T1->... and
so on.
If the loop ends at off state (End of T3), the LED will
be off state at last. If the loop ends at on state (End
of T1), the LED will run an extra T4&T1, which are
not included in loop.
LB
00
01
10
11
Loop Beginning Time
Loop begin from T1
Loop begin from T2
Loop begin from T3
Loop begin from T4
LE
00
01
Loop End Time
Loop end at off state (End of T3)
Loop end at on state (End of T1)
LTA
0000
0001
0010
…
1111
8-11 Bits Of Loop Times
Endless loop
1
2
…
15
Total loop times= LTA ×256 + LTB.
For example, if LTA=2, LTB=100, the total loop times
is 256×2+100= 612 times.
LTB
0000 0000
0000 0001
0000 0010
…
1111 1111
0-7 Bits Of Loop Times
Endless loop
1
2
…
255
0Eh Time Update Register (02h~0Dh)
The data sent to the time registers (02h~0Dh) will be
stored in temporary registers. A write operation of
“0000 0000” data to the Time Update Register is
required to update the registers (02h~0Dh). Please
follow Figure 16 to enable the Auto Breath mode and
update the time parameters.
Table 19 0Fh SWy Pull-Up Resistor Selection
Register
Bit
D7:D3
D2:D0
Name
-
PUR
Default
00000
000
Set pull-up resistor for SWy.
PUR
000
001
010
011
100
101
110
111
SWy Pull-up Resistor Selection Bit
No pull-up resistor
0.5kΩ pull-up in tNOL
1.0kΩ pull-up in tNOL
2.0kΩ pull-up in tNOL
4.0kΩ pull-up in tNOL
8.0kΩ pull-up in tNOL
16kΩ pull-up in tNOL
32kΩ pull-up in tNOL
Figure 11 Auto Breathing Function
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Rev. F, 08/01/2022
19
IS31FL3733
Table 20 10h CSx Pull-Down Resistor Selection
Register
Bit
D7:D3
D2:D0
Name
-
PDR
Default
00000
000
11h Reset Register
Once user read the Reset Register, IS31FL3733 will
reset all the IS31FL3733 registers to their default
value. On initial power-up, the IS31FL3733 registers
are reset to their default values for a blank display.
Set the pull-down resistor for CSx.
PDR
000
001
010
011
100
101
110
111
CSx Pull-down Resistor Selection Bit
No pull-down resistor
0.5kΩ pull-down in tNOL
1.0kΩ pull-down in tNOL
2.0kΩ pull-down in tNOL
4.0kΩ pull-down in tNOL
8.0kΩ pull-down in tNOL
16kΩ pull-down in tNOL
32kΩ pull-down in tNOL
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Rev. F, 08/01/2022
20
IS31FL3733
APPLICATION INFORMATION
Figure 12 Scanning Timing
SCANING TIMING
PWM CONTROL
As shown in Figure 12, the SW1~SW12 is turned on
by serial, LED is driven 16 by 16 within the SWy
(x=1~12) on time (SWy, y=1~12) is sink and pull low
when LED on), including the non-overlap blanking time
during scan, the duty cycle of SWy (active low, y=1~12)
is:
After setting the IOUT and GCC, the brightness of each
LEDs (LED average current (ILED)) can be modulated
with 256 steps by PWM Register, as described in
Formula (1).
Duty =
128μs
1
1
× =
(128μs + 8μs) 12 12.75
(2)
Where 128μs is tSCAN, the period of scanning and 8μs
is tNOL, the non-overlap time.
EXTERNAL RESISTOR (REXT)
The output current for each CSx can be can be set by
a single external resistor, REXT, as described in
Formula (3).
IOUT =
840 GCC
×
REXT 256
(3)
GCC is Global Current Control Register (PG3, 01h)
data showing in Table 14.
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Rev. F, 08/01/2022
I LED =
PWM
× I OUT × Duty
256
(1)
Where PWM is PWM Registers (PG1, 00h~BFh) data
showing in Table 10.
For example, in Figure 1, REXT = 20kΩ, if PWM=255,
and GCC=255, then
I LED =
255
840
255
1
×
×
×
= 3 .29 mA
256 20 k Ω 256 12 .75
Writing new data continuously to the registers can
modulate the brightness of the LEDs to achieve a
breathing effect.
LED AVERAGE CURRENT (ILED)
As described in Formula (1), the LED average current
(ILED) is effected by 3 factors:
21
IS31FL3733
2. Global Current Control Register (PG3, 01h). This
register adjusts all CSx (x=1~16) output currents by
256 steps as shown in Formula (3).
3. PWM Registers (PG1, 00h~BFh), every LED has an
own PWM register. PWM Registers adjust individual
LED average current by 256 steps as shown in
Formula (1).
GAMMA CORRECTION
In order to perform a better visual LED breathing effect
we recommend using a gamma corrected PWM value
to set the LED intensity. This results in a reduced
number of steps for the LED intensity setting, but
causes the change in intensity to appear more linear to
the human eye.
Gamma correction, also known as gamma
compression or encoding, is used to encode linear
luminance to match the non-linear characteristics of
display. Since the IS31FL3733 can modulate the
brightness of the LEDs with 256 steps, a gamma
correction function can be applied when computing
each subsequent LED intensity setting such that the
changes in brightness matches the human eye’s
brightness curve.
Table 21 32 Gamma Steps with 256 PWM Steps
C(0)
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
C(7)
0
1
2
4
6
10
13
18
C(8)
C(9)
C(10)
C(11)
C(12)
C(13)
C(14)
C(15)
22
28
33
39
46
53
61
69
C(16)
C(17)
C(18)
C(19)
C(20)
C(21)
C(22)
C(23)
78
86
96
106
116
126
138
149
C(24)
C(25)
C(26)
C(27)
C(28)
C(29)
C(30)
C(31)
161
173
186
199
212
226
240
255
256
Table 22 64 Gamma Steps with 256 PWM Steps
C(0)
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
C(7)
0
1
2
3
4
5
6
7
C(8)
C(9)
C(10)
C(11)
C(12)
C(13)
C(14)
C(15)
8
10
12
14
16
18
20
22
C(16)
C(17)
C(18)
C(19)
C(20)
C(21)
C(22)
C(23)
24
26
29
32
35
38
41
44
C(24)
C(25)
C(26)
C(27)
C(28)
C(29)
C(30)
C(31)
47
50
53
57
61
65
69
73
C(32)
C(33)
C(34)
C(35)
C(36)
C(37)
C(38)
C(39)
77
81
85
89
94
99
104
109
C(40)
C(41)
C(42)
C(43)
C(44)
C(45)
C(46)
C(47)
114
119
124
129
134
140
146
152
C(48)
C(49)
C(50)
C(51)
C(52)
C(53)
C(54)
C(55)
158
164
170
176
182
188
195
202
C(56)
C(57)
C(58)
C(59)
C(60)
C(61)
C(62)
C(63)
209
216
223
230
237
244
251
255
256
224
192
160
128
96
64
224
32
192
PWM Data
Choosing more gamma steps provides for a more
continuous looking breathing effect. This is useful for
very long breathing cycles. The recommended
configuration is defined by the breath cycle T. When
T=1s, choose 32 gamma steps, when T=2s, choose
64 gamma steps. The user must decide the final
number of gamma steps not only by the LED itself,
but also based on the visual performance of the
finished product.
PWM Data
1. REXT, resistor which is connected R_EXT pin and
GND. REXT sets the current of all CSx (x=1~16) based
on Formula (3).
0
0
8
16
160
32
40
48
56
64
Intensity Steps
128
Figure 14 Gamma Correction (64 Steps)
Note: The data of 32 gamma steps is the standard value and the
data of 64 gamma steps is the recommended value.
96
64
OPERATING MODE
32
0
24
0
4
8
12
16
20
24
Intensity Steps
Figure 13 Gamma Correction (32 Steps)
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Rev. F, 08/01/2022
28
32
Each dot of IS31FL3733 has two selectable operating
modes, PWM Mode and Auto Breath Mode.
PWM Mode
By setting the Auto Breath Mode Register bits of the
Page 2 (PG2, 00h~BFh) to “00”, or disable the B_EN
bit of Configure Register (PG3, 00h), the IS31FL3733
22
IS31FL3733
operates in PWM Mode. The brightness of each LED
can be modulated with 256 steps by PWM registers.
For example, if the data in PWM Register is “0000
0100”, then the PWM is the fourth step.
Writing new data continuously to the registers can
modulate the brightness of the LEDs to achieve a
breathing effect.
Auto Breath Mode
By setting the B_EN bit of the Configuration Register
(PG3, 00h) to “1”, breath function enables. When set
the B_EN bit to “0”, breath function disables.
By setting the Auto Breath Mode Register bits of the
Page 2 (PG2, 00h~BFh) to “01” (ABM-1), “10” (ABM-2)
or “11” (ABM-3), the IS31FL3733 operates in Auto
Breath Mode.
IS31FL3733 has three auto breath modes, Auto Breath
Mode 1, Auto Breath Mode 2 and Auto Breath Mode 3.
Each ABM has T1, T2, T3 and T4, as shown below:
OPEN/SHORT DETECT FUNCTION
IS31FL3733 has open and short detect bit for each
LED.
By setting the OSD bit of the Configuration Register
(PG3, 00h) from “0” to “1”, the LED Open Register
and LED Short Register will start to store the
open/short information and after at least 2 scanning
cycle (3.264ms) the MCU can get the open/short
information by reading the 18h~2Fh/30h~47h, for
those dots are turned off via LED On/Off Registers
(PG0, 00h~17h), the open/short data will not get
refreshed when setting the OSD bit of the
Configuration Register (PG3, 00h) from “0” to “1”.
The Global Current Control Register (PG3, 01h) need
to set to 0x01 in order to get the right open/short data.
The detect action is one-off event and each time
before reading out the open/short information, the
OSD bit of the Configuration Register (PG3, 00h)
need to be set from “0” to “1” (clear before set
operation).
INTERRUPT CONTROL
Figure 15 Auto Breathing Function
T1/T3 is variable from 0.21s to 26.88s, T2/T4 is
variable from 0s to 26.88s, for each loop, the start
point can be T1~T4 and the stop point can be on state
(T2) and off state (T4), also the loop time can be set to
1~212 times or endless. Each LED can select ABM1~ABM-3 to work.
The setting of ABM-1~ABM-3 (PG2, 02h~0Dh) need to
write the 0Eh in PG3 to update before effective.
IS31FL3733 has an INTB pin, by setting the Interrupt
Mask Register (F0h), it can be the flag of LED open,
LED short or the finish flag of ABM-1, ABM-2, and
ABM-3.
For example, if the IO bit of the Interrupt Mask
Register (F0h) set to “1”, when LED open happens,
the INTB will pull be pulled low and the OB bit of
Interrupt Status Register (F1h) will store open status
at the same time.
The INTB pin will be pulled high after reading the
Interrupt Status Register (F1h) operation or it will be
pulled high automatically after it stays low for 8ms
(Typ.) if the IAC bit of Interrupt Mask Register (F0h) is
set to “1”. The bits of Interrupt Status Register (F1h)
will be reset to “0” after INTB pin pulled high.
SYNCHRONIZE FUNCTION
SYNC bits of the Configuration Register (PG3, 00h)
sets SYNC pin input or output synchronize clock
signal. It is used for more than one part working
synchronize. When SYNC bits are set to “01”, SYNC
pin output synchronize clock to synchronize other
parts as master. When SYNC bits are set to “10”,
SYNC pin input synchronize clock and work
synchronization with this input signal as slave. When
SYNC bits are set to “00/11”, SYNC pin is high
impedance, and synchronize function is disabled.
SYNC bit default state is “00” and SYNC pin is high
impedance when power up.
DE-GHOST FUNCTION
Figure 16 Enable Auto Breath Mode
If not follow this flow, first loop’s start point may be
wrong.
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The “ghost” term is used to describe the behavior of
an LED that should be OFF but instead glows dimly
when another LED is turned ON. A ghosting effect
typically can occur when multiplexing LEDs. In matrix
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IS31FL3733
architecture any parasitic capacitance found in the
constant-current outputs or the PCB traces to the
LEDs may provide sufficient current to dimly light an
LED to create a ghosting effect.
stop scanning, and keep working in test mode. So we
recommend for white goods applications, writing
these registers repeatedly like every 5 seconds to
prevent the IC entering test mode without quitting.
To prevent this LED ghost effect, the IS31FL3733 has
integrated pull-up resistors for each SWy (y=1~12) and
pull-down resistors for each CSx (x=1~16). Select the
right SWy pull-up resistor (PG3, 0Fh) and CSx pulldown resistor (PG3, 10h) which eliminates the ghost
LED for a particular matrix layout configuration.
1. Write FDh with 0x03 enter page 3, if it is in page 3,
skip this step.
2. Write E0h with 0x01 to enter test mode
3. Write E1h with 0x00 to quit the ‘SWy stop
scanning’ status.
4. Write E2h with 0x00 to default value
5. Write E3h with 0x00 to default value
6. Write E0h with 0x01 to quit and prevent entering
test mode.
Below are definition of test related registers.
Typically, selecting the 32kΩ will be sufficient to
eliminate the LED ghost phenomenon.
The SWy pull-up resistors and CSx pull-down resistors
are active only when the CSx/SWy outputs are in the
OFF state and therefore no power is lost through these
resistors
Table 21 E0h Test Mode Enable Register
Bit
D7:D1
D0
I2C RESET
Name
-
TEST_PT
The I2C will be reset if the IICRST pin is pull-high,
when normal operating the I2C bus, the IICRST pin
need to keep low.
Default
0000 000
0
SHUTDOWN MODE
Test mode enable register has two functions, first it is
the entrance of the test mode, second it also protects
the other test registers been miswritten.
Shutdown mode can be used as a means of reducing
power consumption. During shutdown mode all
registers retain their data.
TEST_PT
0
Software Shutdown
By setting SSD bit of the Configuration Register (PG3,
00h) to “0”, the IS31FL3733 will operate in software
shutdown mode. When the IS31FL3733 is in software
shutdown, all current sources are switched off, so that
the matrix is blanked. All registers can be operated.
Typical current consume is 3μA.
Hardware Shutdown
The chip enters hardware shutdown when the SDB pin
is pulled low. All analog circuits are disabled during
hardware shutdown, typical the current consume is
3μA.
The chip releases hardware shutdown when the SDB
pin is pulled high. During hardware shutdown state
Function Register can be operated.
If VCC has risk drop below 1.75V but above 0.1V during
SDB pulled low, please re-initialize all Function
Registers before SDB pulled high.
TEST MODE
In order to test or adjust some items of the IC, the
IS31FL3733 has some registers in test mode. In test
mode, the scanning of the SW can be stopped and
some parameters can be adjusted by setting the
register bits of certain registers. Test mode is not
allowed to enter in normal operations, but in some bad
conditions like keep doing EFT (Electrical Fast
Transient) test in power system, very low risk that the
I2C bus will mis-write those registers and let the IC
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1
Test mode protect bit
Disable test mode, E1h~E3h cannot
be accessed
Enable test mode, E1h~E3h can be
accessed
Table 22 E1h Test Mode Data Register 1
Bit
D7:D4
D3:D0
Name
-
SW_S
Default
0000
0000
When normal operation, SW1~SW12 are always
scanning as the timing of Figure 12, if SW_S bits are
set to “0001”~”0111”, SWy stop scanning’ status and
one of the SWy will be selected as the power output
all the time.
SW_S
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
SWy Setting
SW1 always on, other SWy float
SW2 always on, other SWy float
SW3 always on, other SWy float
SW4 always on, other SWy float
SW5 always on, other SWy float
SW6 always on, other SWy float
SW7 always on, other SWy float
SW8 always on, other SWy float
SW9 always on, other SWy float
SW10 always on, other SWy float
SW11 always on, other SWy float
SW12 always on, other SWy float
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IS31FL3733
3
Table 23 E2h Test Mode Data Register 2
D7:D3
D2:D0
Name
-
TRIM_CS
Default
00
000
Table 24 E3h Test Mode Data Register 3
Bit
D7:D4
D3:D0
Name
TRIM_BG
TRIM_OSC
Default
0000
0000
eTQFP-48
Power Dissipation (W)
Bit
2.5
2
1.5
1
0.5
Data register 2 and 3 can change the voltage of
R_EXT pin (TRIM_BG), adjust the internal oscillator
frequency (TRIM_OSC) and trim the average output
current of all CSx (TRIM_CS), when normal operation,
these registers must keep default value, otherwise
those parameters will be changed permanently.
0
-40
-25
≈IPVCC×PVCC – IPVCC×VF(AVR)
≈IPVCC×(PVCC – VF(AVR))
Where IPVCC is the current of PVCC and VF(AVR) is the
average forward of all the LED.
For example, if REXT=20kΩ, GCC=255, PWM=255,
PVCC=5V, VF(AVR)=3.5V@42mA,
then the IPVCC=42mA×16×12/12.75=632.5mA.
50
65
80
95
110 125
80
95
110 125
QFN-48
2.5
2
1.5
1
0.5
0
-40
When operating the chip at high ambient temperatures,
or when driving maximum load current, care must be
taken to avoid exceeding the package power
dissipation limits. The maximum power dissipation can
be calculated using the following Equation (5):
125°C − 25°C
θ JA
-25
-10
5
20
35
50
65
Temperature (°C)
P3733=632.5mA×(5V-3.5V)=0.948.75W
And, PD ( MAX ) =
35
Figure 17 Dissipation Curve
Power Dissipation (W)
P3733=IPVCC×PVCC+ IQ×DVCC(AVCC) – IPVCC×VF(AVR)
(4)
PD ( MAX ) =
20
3
The power dissipation of the IS31FL3733 can
calculate as below:
So,
5
Temperature (°C)
POWER DISSIPATION
PD ( MAX ) =
-10
(5)
125°C − 25°C
≈ 2.56W (eTQFP )
39°C / W
125°C − 25°C
≈ 2.67W (QFN )
37.5°C / W
Figure 17 and 18, shows the power derating of the
IS31FL3733 on a JEDEC boards (in accordance with
JESD 51-5 and JESD 51-7) standing in still air.
Figure 18 Dissipation Curve
LAYOUT
As described in external resistor (REXT), the chip
consumes lots of power. Please consider below
factors when layout the PCB.
1. The VCC (PVCC, DVCC, AVCC, VIO) capacitors
need to close to the chip and the ground side should
well connected to the GND of the chip.
2. REXT should be close to the chip and the ground
side should well connect to the GND of the chip.
3. The thermal pad should connect to ground pins and
the PCB should have the thermal pad too, usually this
pad should have 16 or 25 via thru the PCB to other
side’s ground area to help radiate the heat. About the
thermal pad size, please refer to the land pattern of
each package.
4. The CSx pins maximum current is 42mA
(REXT=20kΩ), and the SWy pins maximum current is
672mA (REXT=20kΩ), the width of the trace, SWy
should have wider trace then CSx.
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IS31FL3733
5. In the middle of SDA and SCL trace, a ground line is
recommended to avoid the effect between these two
lines.
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Rev. F, 08/01/2022
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IS31FL3733
CLASSIFICATION REFLOW PROFILES
Profile Feature
Pb-Free Assembly
Preheat & Soak
Temperature min (Tsmin)
Temperature max (Tsmax)
Time (Tsmin to Tsmax) (ts)
150°C
200°C
60-120 seconds
Average ramp-up rate (Tsmax to Tp)
3°C/second max.
Liquidous temperature (TL)
Time at liquidous (tL)
217°C
60-150 seconds
Peak package body temperature (Tp)*
Max 260°C
Time (tp)** within 5°C of the specified
classification temperature (Tc)
Max 30 seconds
Average ramp-down rate (Tp to Tsmax)
6°C/second max.
Time 25°C to peak temperature
8 minutes max.
Figure 19 Classification Profile
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Rev. F, 08/01/2022
27
IS31FL3733
PACKAGE INFORMATION
QFN-48
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Rev. F, 08/01/2022
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IS31FL3733
eTQFP-48
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Rev. F, 08/01/2022
29
IS31FL3733
RECOMMENDED LAND PATTERN
QFN-48
eTQFP-48
Note:
1. Land pattern complies to IPC-7351.
2. All dimensions in MM.
3. This document (including dimensions, notes & specs) is a recommendation based on typical circuit board manufacturing parameters. Since
land pattern design depends on many factors unknown (eg. User’s board manufacturing specs), user must determine suitability for use.
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Rev. F, 08/01/2022
30
IS31FL3733
REVISION HISTORY
Revision
Detail Information
Date
A
Initial release
2016.07.01
B
1. Update READING OPERATION
2. Correct error of REGISTER DEFINITION-2
3. Update Figure 8
2016.12.20
C
1. Correct REGISTER DEFINITION-2 and Table 2
2. Update land pattern
3. Add ICC and VHR at GCC=0x12
2018.09.25
D
Add Test Mode section in APPLICATION INFORMATION
2018.12.17
E
Add NRND watermark
2021.10.21
F
Remove NRND watermark
2022.08.01
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Rev. F, 08/01/2022
31