THF9306A - THine Electronics, Inc.

THL3504_Rev.1.10_E

THL3504

24-channel Constant Current LED Driver with LVDS Interface

DESCRIPTIONS

The THL3504 i s an LED driver with 24 channe l constant

current sink outputs. The constant current values for

three output groups are determined by external resistors.

The embedded oscillator and PWM controller

individually generates 256-step brightness set by the

dedicated registers for each channel.

The serial interface of 2-pair LVDS lines (clock and

data) features high-level noise tolerance, high-speed, and

long-distance transmission.

The LVDS allowing cascaded and multidrop connection

offers the maximum flexibility for designers to place and

connect LED drivers.

The simple and one-way communication protocol is

easily-controlled and requires less CPU resources.

APPLICATIONS

Amusement

LED Backlight

LED Display

Digital Signage

Illumination

FEATURES

< Driver part >

- Constant Current Output: 24 channels

- Output Sink Current: up to 40mA/ch

- Output voltage: up to 40V

- Individual Brightness Control: 256 steps

- Group Brightness Control: 64 steps

- Output disable/enable

< Serial interface part >

- 2-pair Serial LVDS Input or 3-wire Serial CMOS Input

up to 10Mbps

- Bridge Function Converting 3-wire Serial

CMOS Input to 2-pair Serial LVDS Output

- Repeater function of 2-pair Serial LVDS Input / Output

with Waveform and Timing Correction

- Device Address Selection up to 62 addresses

- General call to all devices

Protection Circuits

UVLO, Short Circuit Protection, Thermal Shutdown

Supply Voltage: 3.0~5.5V

Package: QFN 48-pin Exposed Pad

Input Logic

Registers

Constant

Address Data

PWM Controller

A0~A5

SCL_OUTn

SCL_OUTp

SDA_OUTn

SDA_OUTp

SCL_INn

SCL_INp

SDA_INn

SDA_INp

Oscillator

MODE

CSn

SCK SCL

SDA

Block Diagram

SCL

SDA

REXT0

REXT1

REXT2

Current

Generator

Current Sink

3-wire to 2-wire

Re-timing

conversion

LVDS Input LVDS Output

OUT0~OUT7 OUT8~OUT15 OUT16~OUT23

Current Sink

THL3504_Rev.1.10_E

ABSOLUTE MAXIMUM RATINGS

*Note1: As for the A0 pin, the maximu m value is VDD+0.5V. While power su ppl y is not applied, the vol tage on the A0

pin must be lower than 0.5V.

RECOMMENDED OPERATING CONDIT IONS

*Note2: Since overshoot of current waveform may occur depending on usage conditions, the LEDs with more than

80mA pulse forward current as absolute maximum ratings are recommended

ELECTRICAL CHARACTERISTICS

Parameter Condition Min Typ Max Unit

VDD Supply Voltage -0.4 6.0 V

Digital Input Voltage *Note１-0.5 6.0 V

LED Driver Output Voltage 40 V

Storage Temperature -55 150 °C

Junction Temperature, Tj 150 °C

Parameter Condition Min Typ Max Unit

VDD Supply Voltage 3.0 5.5 V

LED Driver Output Voltage 35 V

LED Driver Output Current *Note2 40 mA/ch

Operating Ambient Temperature, Ta -40 85 °C

Parameter Min Typ Max Unit

11 mA

18 mA

13 mA

21 mA

28 mA

10 MHz

2.5 V

0.1 V

±3 %

±6 %

10 μA

0.7VDD V

0.3VDD V

0.05VDD V

±10 μA

VIC=1.2V ±100 mV

±30 μA

VDD=3.0V 240 mV

VDD=3.3V 350 mV

VDD=5.0V 420 mV

VDD=5.5V 480 mV

1.1 1.25 1.4 V

Condtion

VDD=3.3V, Iout=20mA(REXT=2.4kΩ)

without LVDS output termination resistors

VDD=3.3V, Iout=20mA(REXT=2.4kΩ)

with LVDS output termination resistors 100Ω

VDD=5.0V, Iout=20mA(REXT=2.4kΩ)

without LVDS output termination resistors

VDD=5.0V, Iout=20mA(REXT=2.4kΩ)

with LVDS output termination resistors 100Ω

VDD

Supply Current

*Note1

VDD=5.0V, Iout=20mA(REXT=2.4kΩ)

with LVDS output termination resistors 100Ω

UVLO Threshold Voltage (VDD Rising)

Osillator Frequency(fosc)

UVLO Hysteresis

Constant Current Mismatch Between Channels

Constant Current Mismatch Between Devices

LED Driver Output Leakage Current

Digital Input, High Level Voltage (VIH)

Digital Input, Low Level Voltage (VIL)

Digital Input, Hysteresis

LVDS Output, Common Mode Voltage (VOC)

Digital Input, Leakage Current

LVDS Input, Differential Voltage (VID)

LVDS Input, Leakage Current

LVDS Output, Differential Voltage (VOD)

THL3504_Rev.1.10_E

3-wire Serial CMOS Level Input (MODE=High)

2-pair Serial LVDS Output

2-pair Serial LVDS Input (MODE=Low)

*1. In cascading connection, termination resistors are necessary for LVDS outputs. In this case, 2.4mA to 4.8mA current

flows at each resistor depending on the power supp ly volt age. Therefore, the current consumption is larger than the case

without the termination resistors.

*2. SCL, SDATransition Time Measurement Condition

Symbol Parameter Condition Min Typ Max Unit

fSCK SCK Frequency 10 MHz

tCH SCK High Time 40 ns

tCL SCK Low Time 40 ns

tDVCH SI Setup Time 10 ns

tCHDX SI Hold Time 10 ns

tCHSL CSn Not Active Hold Time 40 ns

tSLCH CSn Active Setup Time 40 ns

tCHSH CSn Active Hold Time 40 ns

tSHCH CSn Not Active Setup Time 40 ns

tSHSL CSn Not Active Time 200 ns

Symbol Parameter Condition Min Typ Max Unit

tr, tf SCL, SDA Transition T ime *2 10 ns

tSTAH Header Condition Hold Time 6 10 20 ns

tDSU SDA Setup Time 6 1 0 20 ns

tDHO SCL Falling Edge Hold Time 5 ns

tPWE End Pulse Width 25 40 70 ns

tPD SCL Propagation Delay 30 ns

Symbol Parameter Condition Min Typ Max Unit

fSCL SCL Frequency 10 MHz

tDAH SCL High Time 25 ns

tDAL SCL Low Time 25 ns

tSTAH Header Condition Hold Time 4 ns

tDSU SDA Setup Time 4 ns

tDHO SCL Falling Edge Hold Time 3 ns

SCL_OUTp

SCL_OUTn

SDA_OUTp

SDA_OUTn

100Ω

Open

< Without termination resistors >< With termination resistors >

Termination Resistor:100Ω

OUTp

OUTn

Load Capacitance:50pF

THL3504_Rev.1.10_E

* Abbreviation

This document refers to the differential signals in unipolar shorthand; for example, SCL_IN, SDA_IN, SCL_OUT, and

SDA_OUT mean (SCL_INp - SCL_INn), (SDA_INp - SDA_INn), (SCL_OUTp - SCL_OUTn), and (SDA_OUTp -

SDA_OUTn) respectively.

* A falling transition of the SDA_IN while the SCL_IN is high is defined as ”Header Condition“. Please refer to the sec-

tion “2-pai r S erial LVDS Input” for detai ls.

INp: SCL_INp, SDA_INp

INn: SCL_INn, SDA_INn

OUTp

OUTn

OUTp-OUTn 0V

VOC=(OUTp+OUTn)/2

VOD

80%

20%

tr tf

LVDS Spec

INp

INn VID

OUTp: SCL_OUTp, SDA_OUTp

OUTn: SCL_OUTn, SDA_OUTn

VIC=(INp+INn)/2

Bit 7 Bit 0

tCHSL tSLCH tCHSH tSHCH

tCH

tCL

tDVCH tCHDX

Bit 0Bit 7

tSHSL

tSTAH

tDAL tDAH

tDSU tDHO

tPWE

SCL_IN

SDA_IN

CSn

SCK

Bit 0

Bit 7

tPD

Header Condition

tPD

Bit 0Bit 7

SCL_OUT

SDA_OUT

SCL_OUT

SDA_OUT

End Pulse

tSTAH tDSU tDHO

Header Condition

Timing Diagram

3-wire Serial Input/2-pair Serial LVDS Output Timing

2-pair Serial LVDS Input/Output Timing

THL3504_Rev.1.10_E

PIN CONFIGURATIONS

* The exposed pad is connected to GND inside the device.

PIN DESCRIPTION

OUT23

OUT22

OUT21

OU T20

OUT19

OUT18

MODE

REXT2

VDD

REXT1

48 47 46 45 44 43 42 41 40 39 38 37

GN D 136

OU T17

SDA_INn 235

OU T16

SDA_INp 334

OU T15

SCL_INn 433

OU T14

SCL_INp 532

OU T13

VDD 631

OU T12

GN D 730

OU T11

SCL_OUTp 829

OU T10

SCL_OUTn 928

OUT9

SDA_OUTp 10 27 OUT8

SDA_OUTn 11 26 OUT7

GN D 12 25 OUT6

13 14 15 16 17 18 19 20 21 22 23 24

OUT0

OUT1

OUT2

OU T3

OUT4

OUT5

VDD

REXT0

(Top View)

Exposed Pad

(Bottom Side)

Pin Name T ype Description

MODE Digital Input

Serial Interface Input Mode Select

Low: 2-pair Serial LVDS Input

High: 3-wire Serial CMOS Input

SCL_ INp(SC K) LVDS Input/

Digital Input

MODE=Low: 2-pair Serial LVDS Clock Input - Positive

MODE=High: 3-wire Serial Clock Input (SCK)

SCL_IN n(CSn) LVDS Input/

Digital Input

MODE=Low: 2-pair Serial LVDS Clock Input - Negative

MODE=High: 3-wire Serial Chip Select Input (CSn)

SDA_ INp(SI) LVDS Input/

Digital Input

MODE=Low: 2-pair Serial LVDS Data Input - Positive

MODE=High: 3-wire Serial Data Input (SI)

SDA_INn LVDS Input/

Digital Input

MODE=Low: 2-pair Serial LVDS Data Input - Negative

MODE=High: R eserved (Connect to Low)

SCL_OUTp LVDS Output 2-pair Serial LVDS Clock Output - Positive

SCL_OUTn LVDS Output 2-pair Serial LVDS Clock Output - Negative

SDA_OUTp LVDS Output 2-pair Serial LVDS Data Output - Positive

SDA_OUTn LVDS Output 2-pair Serial LVDS Data Output - Negative

OUT0-OUT23 Constant

Current Out

ut LED Driver Output Chan nel 0 - 23

REXT0 Analog Output Resistor connection for the constant current outputs (OUT0-OUT7)

REXT1 Analog Output Resistor connection for the constant current outputs (OUT8-OUT15)

REXT2 Analog Output Resistor connection for the constant current outputs (OUT16-OUT23)

A0-A5 Digital Input Device address input Bit0 - 5

VD D ―Power supply

GND ―Ground

THL3504_Rev.1.10_E

Address is noted in hex with the prefix “R“. For example, R00 is a register of address 00.

Bit location is noted by “[]“. For example, R00[5:0] is bit 5 down to bit 0 of address 00.

Address Default Function Description

R00[7] 0 PWM Phase Control Mode 0: Normal Mode

1: Group Control Mode

R00[6] 0 LED Output Enable 0: Output Disable

1: Output Enable

R00[5:0] 000000b Global Brightness Global Brightness=(Value+1)/64

R01[7:0] 00h Individual Brightness - OUT0

R02[7:0] 00h Individual Brightness - OUT1

R03[7:0] 00h Individual Brightness - OUT2

R04[7:0] 00h Individual Brightness - OUT3

R05[7:0] 00h Individual Brightness - OUT4

R06[7:0] 00h Individual Brightness - OUT5

R07[7:0] 00h Individual Brightness - OUT6

R08[7:0] 00h Individual Brightness - OUT7

R09[7:0] 00h Individual Brightness - OUT8

R0A[7:0] 00h Individual Brightness - OUT9

R0B[7:0] 00h Individual Brightness - OUT10

R0C[7:0] 00h Individual Brightness - OUT11

R0D[7:0] 00h Individual Brightness - OUT12

R0E[7:0] 00h Individual Brightness - OUT13

R0F[7:0] 00h Individual Brightness - OUT14

R10[7:0] 00h Individual Brightness - OUT15

R11[7:0] 00h Individual Brightness - OUT16

R12[7:0] 00h Individual Brightness - OUT17

R13[7:0] 00h Individual Brightness - OUT18

R14[7:0] 00h Individual Brightness - OUT19

R15[7:0] 00h Individual Brightness - OUT20

R16[7:0] 00h Individual Brightness - OUT21

R17[7:0] 00h Individual Brightness - OUT22

R18[7:0] 00h Individual Brightness - OUT23

Individual Brightness=Value/256

THL3504_Rev.1.10_E

FUNCTIONAL DESCRIPTION

External reference resistor

The constant current value of LED driver output channels are determined by the resist ors connected between REXT0,

REXT1, REXT2 and GND. The external resistor value is calculated by the following equation.

For example, when Iout=20mA, REXT=0.6/20 x 80=2.4[kΩ]

Writing to registers

The device includes 25-byte registers (R00-R18 ) for setting. Writing to registers is executed through the serial interface

and the value is maintained as long as power is applied. The register value can not be read.

Writing to registers should be invoked aft er the power supply (VD D) of all the devices in cascading and multidrop con-

nection gets stable above 3.0V.

Then after power-up, if using 2-pair serial LVDS input, initialization of 2-pair serial LVDS input must be done before

writing to registers. However, in case all the registers are continuously rewritten, in other words repeatedly refreshed, the

initialization of 2-pair serial LVDS input is not necessary after pow er-up and instantaneous interrupti on.

Please refer to the section “Initialization of 2-pair Serial LVDS Input” for details.

UVLO

The device ha s an internal UV LO (Under-Volta ge Locked-O ut) circuit to prevent the device from malfunction at low

supply voltage. Until power supply (VDD) has reached 2.5V (typical value), the UVLO holds the internal logic circuit in

a reset condition, and keeps the LED driver outputs and LVDS outputs in Hi-Z state. The UVLO circuit has hysteresis. If

power supply falls below 2.4V (typical value), the device gets into the above UVLO state in which the internal logic

circuit is reset and the regsiters are reset to default value.

Short Circuit Protection

The device includes short circuit protection circuits for each pin of the external reference resistor s, REXT0-REXT2 to

prevent the LED driver outputs from driving excessive current. If LED driver outputs turn on with the REXT0-REXT2

pin shorted to such as GND, overcurrent flowing in output transistors may causes permanent damage to the device.

The short circuit protection is a function to shutdown outputs immediately when the device detects short circuit condition

on REXT0-REXT2 pin. If short circuit condition is resolved, normal operation automatically resumes.

However, this function can not always prevent breakdown or damage to the device depending on usage situation and

duration of abnormality.

Thermal Shutdown

The device includes thermal shutdown c ircuit to prevent d amages caused by exc essive heat. If the jun ction temperatu re

exceeds the absolute maximum rating (Tj=150°C), the thermal shutdown circuit turn off all LED driver outputs. The

thermal shutdown circuits has hysteresis. If Tj falls enough, normal operation automatically resumes.

However, this function can not always prevent breakdown or damage to the device depending on usage situation and

duration of abnormality.

REXT[kΩ]= 0.6 [V]

Iout [mA] ×80 (Typical Value at Iout=20mA)

Internal Reset Signal

Power Supply(VDD)

UVLO Threshold(2.5V typ.)

Hysterisys (0.1V typ.)

(Active-Low)

THL3504_Rev.1.10_E

Serial Communication Protocol

2-pair serial LVDS input or 3-wire serial CMOS level input is selected as a serial interface for register setting by the

MODE pin. The 2-pair serial LVDS input and 3-wire serial CMOS level input share input pins (SCL_INp/SCL_INn,

SDA_INp/SDA_INn) which are used as 2-pair serial LVDS in put when the MODE p in is set to low, and used as 3-wire

serial CMOS level input when the MODE pin is set to high.

- The serial interface is clock synchronous and used only for writing to registers (one-way communication).

- The data length is 8-bit in MSB first bit order. As for how to recognize the first bit, please refer to the section “2-pair

serial LVDS input” and “3-wire serial CMOS level input”.

- The first 8 bits that includes the first bit is defined as “1st byte” and the next 8 bits as “2nd byte” and so on.

- “1st Byte” is assigned to the device address. If device address is set to 00 h, all the devices are selected to be written

except the device which has a device address 00111111 by the A5-A0 pins.

- “2nd Byte” is assigned to the register address.

- The bytes after “3rd Byte” is assigned to register values to write. The register addres s is incremented every time 8-bit

register value is written. For example, the value of “3rd Byte” is written to the register at the address indicated in “2nd

byte“, and the value of “4th byte” is written to the register at the add ress (“2nd byte“+1).

- Don’t write except the registers R00-R18

< Serial Data >

Device Address Setting

The lower 6 bits out of 8-bit serial interface device address are set by the A0-A5 pin.The higher 2 bits are fixed at 00.

For example,

in case A5=Low, A4=Low, A3=Low, A2=Low, A1=Low, A0=High,

the device address is set to 00000001 (01h).

- If the A0-A5 pins are all set to high, the register of the device can not be written. Please set all the A0-A5 pins to high

in order to use onl y 2-pair to 2-pair re peater functi on or 3-wire to 2-pai r bridge func tion withou t using LED driv er out-

puts.

- Since the device address 00000000 (00h) is the one to be used for writing to all devices, basically don’t use it.

- Please set device addresses within the range from 00000001 (0 1h) to 00111110 (3Eh) in normal use.

The first bit

Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit1 Bit0 Bit7 Bit6 Bit5 Bit4 Bit3 Bit2 Bit1 Bit0

Device Address Register Address

1st Byte 2nd Byte

3rd Byte Last Byte

THL3504_Rev.1.10_E

Serial Interface Connection

THL3501 (16-channel open-drain outputs), THL3502(24-channel open-drain outputs), THL3503(16-channel constant-

current outputs), and THL3504(24-channel constant-current outputs) are all communication protocol compatible with

each other so that they can be mixed in cascade and multidrop connection scheme (Please note that multiple LVDS out-

puts can not be connected to each other.).

* THL3501, THL3502, THL3503, and THL3504 are collectively referred to as THL350X hereafter.

Cascade Connection by 2-pair serial LVDS

The THL350X can convert 3-wire serial output from the host such as micro-controller or CPU to 2-pair serial LVDS,

which is connected to the 2-pair serial LVDS input of a following device in a po int-to-point topo logy. As for the max i-

mum number of devices to be cascaded, please refer to an application note.

Multidrop Connection by 2-pair serial LVDS

The THL350X can convert 3-wire serial output from the host such as micro-controller or CPU to 2-pair serial LVDS,

which is connected to the 2-pair serial LVDS input of following multiple devices in a multidrop topology. As for the

maximum number of devices to be multidropped, please refer to an application note.

Multidrop Connection by 3-wire serial

3-wire serial output from the host such as micro-controller or CPU is connected to following multiple devices in a multi-

drop topology.

Host THL350X

SCL

SDA

3-wire serial 2-pair serial LVDS 2-pair serial LVDS

MODE pin=High MODE pin=Low MODE pin=Low

CSn

SCK

THL350X THL350X

Host

SCL

SDA

2-pair serial LVDS

MODE pin=High

MODE pin=Low MODE pin=Low

CSn

SCK

3-wire serial

THL350X

THL350X THL350X

Host

3-wire serial

MODE pin=High MODE pin=High

CSn

SCK

THL350X THL350X

THL3504_Rev.1.10_E

3-wire Serial CMOS Level Input

When the MODE pin is set to high, the serial interface for writing to registers becomes 3-wire serial CMOS level input.

The chip select (CSn), serial clock (SCK), serial data (SI) of 3-wire serial CMOS level input are input to the SCL_INn

pin, the SCL_INp pin, the SDA_IN pin respectively. The SDA_INn must be tied to low.

- While the CSn stays low, the data input SI is latched by rising edges of the clock input SCK .

- The data latched by the first clock rising edge after the CSn falls is assigned the “first bit“.

- The “Last Byte” is written to a register when the CSn rises after Bit0 (in other words, “Last Byte” will not be written to

a register until the CSn rises).

- If the CSn rises in the middle of a byte, th e byte is no t written t o a register, then the co mmuni cation resu mes from “1st

Byte” when the CSn falls next.

< 3-wire Serial CMOS Level Input >

2-pair serial LVDS

When the MODE pin is set to low, the serial interface for writing to registers becomes 2-pair serial LVDS input

(SCL_INp/SCL_INn, SDA_INp/SDA_INn).

- The data input SDA_IN is latched by rising edges of the clock input SCL_IN.

- A falling transition of the SDA_IN while the SCL_IN is high is defined as ”Header Condition“, and the data latched by

the first clock rising edge after the “Header Condition” is assigned the “first bit“. Except ”Header Condition”, the transi-

tions of the data input SDA_IN are allowed while th e cloc k inp ut SCL_IN is low.

- The “Last Byte” is written to a register at the reception of an active-low pulse “End Pulse” (actually, “Last Byte” is

written to a register at the rising edge of the “End Pulse“). W hen the “End Pulse” ri ses, the data outp ut SDA _OUT must

be high.

- If the ”Header Condition” is received in the middle of a byte, the byte is not written to a register, then the communica-

tion resumes from “1st Byte“.

< 2-pair serial LVDS input >

* The 3-wire to 2-pair brid ge function can convert 3-wire se rial output from the host such as m icro-controller or CPU to

2-pair sereal LVDS. Please refer to the section “3-wire to 2-pair bridge function” for details.

SCL_INp (SCK)

SDA_INp (SI)

SCL_INn (CSn)

bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0 bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit

bit7 bit6

765432

076 765432

“1st Byte“ “2nd Byte“ “Last Byte“

bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0 bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0bit7 bit6

765432

076 765432

“1st Byte“ “2nd Byte“ “Last Byte“

End Pulse

Header Condition

SCL_IN

SDA_IN

THL3504_Rev.1.10_E

3-wire to 2-pair bridge function

When the MODE pin is set t o high, the serial interface for writing to registers becomes 3-wire serial CMOS level input

(CSn, CK, SI), which is converted to 2-wire se rial and transferred to the LVDS output pins.

- While the CSn is active low, the data input SI is latched and transferred to the LVDS output SDA_OUT on the rising

edges of the clock input SCK. There is about 10ns setup time between the clock output SCL_OUT and the data output

SDA_OUT.

- When the CSn falls, “Header Condition” is generated on 2-pair LVDS outpu t.

- After the CSn rises, an active-low pulse "End Pulse” (the pulse width: 40ns typ) is added on the clock output

SCL_OUT.

- When the CSn rises, the data out put SDA_OUT is forced high. In the result, the low to high transition of the clock out-

put SCL_OUT "End Pulse” occurs while the data output SDA_OU T is high

< 3-wire to 2-pair bridge >

2-pair to 2-pair repeater function

When the MODE pin is set to low, the serial interface for writing to registers becomes 2-pair serial LVDS input

(SCL_INp/SCL_INn, SDA_INp/SDA_INn). The timing between the clock and the data is compensated and then they are

transferred to the LVDS output pins.

- The data input SDA_IN is latched and transferred to the LVDS output SDA_OUT on the rising edges of the clock input

SCL_IN. There is about 10ns setup time between the cl ock output SCL_OUT and the data output SDA_OUT.

- The “Header Condition” is regenerated and transferred to the output.

< 2-pair to 2-pair repeater function >

SCL_INp (SCK)

SDA_INp (SI)

SCL_INn (CSn)

bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0 bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0bit7 bit6

765432

076 765432

bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0 bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0

bit7 bit6

765432

076 765432

“1st Byte“ “2nd Byte“ “Last Byte“

End Pulse

Header Condition

SCL_OUT

SDA_OUT

bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0 bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0

bit7 bit6

765432

076 765432

0End Pulse

Header Condition

SCL_IN

SDA_IN

bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0 bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0

bit7 bit6

765432

076 765432

“1st Byte“ “2nd Byte“ “Last Byte“

SCL_OUT

SDA_OUT

THL3504_Rev.1.10_E

Initialization of 2-pair Serial LVDS Input

After power-up, if using 2-pair serial LVDS input, initialization of 2-pair serial LVDS input must be done before writing

to registers. Without the initialization of 2-pair serial LVDS input, the first writing to regi sters (“1st Byte”-”Last Byte”)

may possibly fail. However, the initialization of 2-pair serial LVDS input is not necessary in case failure in the first writ-

ing to registers can be allowed; for example , in case all the registers (R00-R18) are continuously rewritten, in other

words repeatedly refreshed.

In order to initialize 2-pair serial LVDS input, please input active-low pulse (pulse width: 200ns min.) of the CSn into 3-

wire serial CMOS level input of the first device which converts 3-wire to 2-pair. In consequence, the 2-pair serial LVDS

input of all the following devices are initialized. In cascading connection, it takes the propagation delay of all stages in

cascaded chain to finish the initialization of 2-pair serial LVDS input.

< Initialization of 2-pair Serial LVDS Input >

Host

SCL

SDA

3-wire serial 2-pair serial LVDS 2-pair serial LVDS

CSn

SCK

Active-low pulse input 2-pair serial LVDS inputs to be initialized

THL350X THL350X

765432

SCL_INp (SCK)

SDA_INp (SI)

SCL_INn (CSn)

Initialization Pattern Example 1

(High)

Input active-low pulse input to the CSn

Min.200ns

SCL_OUT

SDA_OUT

(High)

765432

Initialization Pattern

Initialization Pattern Example 2

Input 1st Byte (Device Address)=FFh

SCL_INp (SCK)

SDA_INp (SI)

SCL_INn (CSn)

SCL_OUT

SDA_OUT

3-wire serial

CMOS level input

2-pair serial

LVDS Output

Initialization Pattern

3-wire serial

CMOS level input

2-pair serial

LVDS Output

THL3504_Rev.1.10_E

Individual Brightness Control

The Brightness for each LED output channel (OUT0-OUT23) are individually programmable in 256 steps by the register

configuration (R01-R15). The individual Brightness is contro lled by PWM duty cycle.

The ratio of ON time for the constant current outpu ts is expressed in the follo wing equation.

ON time ratio = Individual Brightness Control Register Value / 256

The bigger setting valu e results in the larger ON time ratio, therefore hi gher brightness. When the register value is 0, the

output current sink is held OFF, therefore the LED turns off.

< Individual Brightness Control >

Global Brightness Control

In addition to the individual brightness control for each LED driver output channels, the brightness of all channe ls is glo-

bally programmable in 64 steps by the register configuration (R00[5:0]). The global brightness controller partially masks

pulses generated by the individual brightness controller.

The ratio of ON time for the constant current outputs which is totally set by both the individual brightness contr ol and

global brightness control is expressed in the following equation.

ON time ratio = (Individual Brightness Control register value/256) x (Global Brightness Control register value+1)/64

The bigger setting value results in the larger ON time ratio, therefore higher brightness.

< Global Brightness Control >

OFF

Individual Brightness:255

ON Dugy=255/256

Individual Brightness:254

ON Dugy =254/256

Individual Brightness:2

ON Dugy=2/256

Individual Brightness:1

ON Dugy =1/256

Individual Brightness:0

ON Dugy =0/256

approximately 27μs

123450678910 63626160

5958575655 12340

123450678910 63626160

5958575655 12340

123450678910 63626160

5958575655 12340

123450678910 63626160

5958575655 12340

123450678910 63626160

5958575655 12340

Global Brightness:63

ON Duty=64/64

Global Brightness:62

ON Duty =63/64

Global Brightness:2

ON Duty =3/64

Global Brightness:1

ON Duty=2/64

Global Brightness:0

ON Duty=1/64

approximately 27μs

approximately 1.7ms

THL3504_Rev.1.10_E

Increment timing of Global Brightness Control

Global brightness control is started soon at the timing of incremented.new resister data and previous data is destructed.

Therefore, please be careful about brightness changes for short periods depending on the timing of increm ented new

data.

< Increment timing of Global Brightness Control >

PWM Phase Control Mode

The PWM pulse start position of each channel is controlled in different phases to reduce switching noise.

The phase control mode is selectable in 2 ways by the register configu rati on (R0 0[7]).

In normal mode (R00[7]=0), the PWM pulse start positions of all channels are different from each other.

In group control mode (R00[7]=1), the PWM pulse start positions of 2 or 3 channel groups are different from each other.

< PWM Phase Control Mode >

1234506789

10 20191817

1615141312 012321

Global Brightness:：7

ON Duty =8/64

resister writing

Global Brightness:：1

ON Duty =2/64

1234506789

10 6543

2101312 8910117

Global Brightness:：7

ON Duty =8/64

resister writing

Global Brightness:：1

ON Duty =2/64

OUT0

OUT1

OUT2

Delay

OUT0

OUT1

OUT2

OUT3

OUT4

OUT5

Delay

Normal Mode(R00[7]=0)

Group Control Mode(R00[7]=1)

Group

Group 1

THL3504_Rev.1.10_E

When multiple LED output channels need to be connected in parallel to driv e, the PWM phase control mode must be set

to group control mode (R00[7]=1), and the channels in th e same group must be connected in parallel to drive.

< Grouping of Group Control Mode >

LED Driver Output Enable

All of the LED driver outputs can be disabled by register configuration (R00 [6]). When disab led (R00[6]= 0), all of the

LED driver outputs go into OFF (Hi-Z) state, LEDs turn off.

OUT(n)

OUT(n+1)

OUT(n+2)

Same group

Pin Name

Group Output Channel

Group0 OUT0, OUT1, OUT2

Group1 OUT3, OUT4, OUT5

Group2 OUT6, OUT7, OUT8

Group3 OUT9, OUT10, OUT11

Group4 OUT12, OUT13, OUT14

Group5 OUT15, OUT16, OUT17

Group6 OUT18, OUT19, OUT20

Group7 OUT21, OUT22, OUT23

THL3504_Rev.1.10_E

Package Dimensions

QFN 48-pin

7.00 bsc

TOP VIEW SIDE VIEW

SEATING PLANE

1 PIN INDEX

Unit:mm

5.50 +/-0.10

BOTTOM VIEW

①

0.09 R MIN

1 PIN INDEX

0.20 R

0.35

0.40 +/-0.05

0.25 +0.05/-0.07

0.50 bsc

0.05

0.45

0.10

0.05 MAX

0.20 REF.

0.65～0.70

0.90 MAX

THL3504_Rev.1.10_E

Notices and Requests

1. T he produ ct s pecificatio ns described in this mater ial ar e s ubject to change without prior not ice.

2. The circu it diagrams described in th is m ater ial ar e examples of the applicat ion which may n ot always app ly to the

cus tomer’s design. We are not r espon sible fo r possibl e err or s and omissions in th is material. Please note if errors or

omissions s ho uld b e f ou nd in th is mat erial, w e may not b e ab le to cor rect them im med iat ely.

3. This material contains our copy right, know-how or other proprietary. Copying or disclosing to third parties the

contents of this material without our pr ior permission is prohibited.

4. N ote that if infr ingement of any third party's indus trial owners hip should occur by us ing this product, we will be

exempted from the responsibility unles s it dir ectly relates to the production process or functions of the product.

5. T his product is presumed to be used for gen eral el ectr ic equ ipme nt, not for the appli cations which r eq uir e very h igh

reliability (including medical equipment directly concerning people's life, aerospace equipment, or nuclear control

equipment). Also, when using this product for the equipment concerned with the control and safety of the

tran spor tation means, th e traffic signal equipment, or various Types of sa fety eq uip ment, please do it after ap ply in g

app ropriate m eas ur es to the pr oduct.

6. Despite our utmost eff orts to improve the quality and reliability of the product, faults will occur with a certain small

probability, which is inevitable to a semi-conductor product. Therefore, you are encouraged to have sufficiently

redu ndant o r err or preven tive design ap plied t o the u se of the prod uct so as not to have o ur prod uct cause an y social

or publi c da mage.

7. Pleas e note that this product is not designed to be radiation-pro of.

8. Customers are asked, if required, to judge by themselves if this product falls under the category of strategic goods

under the For eign Exchan ge and F or eig n Trad e Contr ol Law.