16-Bit Constant Current LED Drivers With LED Open/Short Detection

DM133
Version
: A.024
Issue Date : 2004/07/05
File Name : SP-DM133-A.024.doc
Total Pages : 20
16-Bit Constant Current LED Drivers
With LED Open/Short Detection
新竹市科學園區展業一路 9 號 7 樓之 1
SILICON TOUCH TECHNOLOGY INC.
9-7F-1, Prosperity Road I, Science Based Industrial Park,
Hsin-Chu, Taiwan 300, R.O.C.
Tel：886-3-5645656
Fax：886-3-5645626
點晶科技股份有限公司
DM133
SILICON TOUCH TECHNOLOGY INC.
DM133
16-Bit Constant Current LED Drivers
with LED Open/Short Detection
General Description
The DM133 is a constant current driver specifically designed for LED display
applications. The device includes a 16-bit shift register, two latches, and constant
current drivers on a single Silicon CMOS chip. Its built-in open/short detection and
thermal alarm circuits help the user to detect the overheating of the IC and LED
failures. Its user-friendly design allows the user to adjust the output current (5~60mA)
by using an external resistor. The current also can be further tuned by 6-bit serial
shift-in data.
Features
z
z
z
z
z
z
Constant Current Output:
Current with one resistor for 5mA to 60mA
Maximum Clock Frequency:
25MHz (Max.)
Power Supply Voltage:
3.3V to 5.0V
CMOS Compatible Input/Output
Package:
HSOP28, SSOP28, QFN32
Constant Current Matching:
10mA ~ 60mA :
Bit-to-Bit : ± 4.0% (Max)、
5mA ~ 10mA :
Chip-to-Chip: ± 10.0% (Max)
Bit-to-Bit : ± 6.0% (Max)、
Chip-to-Chip: ± 12.0% (Max)
17V
Error signal output when junction temperature
exceeds limit
z
z
Maximum Output Voltage:
Thermal Alarm Function:
z
z
LED Open/Short Detection:
Error signal output when LED is failed
6 bit Linear Global Current Adjustment
16-Bit Constant Current LED Drivers
-1-
Version：A.024
點晶科技股份有限公司
DM133
SILICON TOUCH TECHNOLOGY INC.
Pin Connection (Top view)
SSOP28
VDD
ENABLE
LATCH
CLOCK
SERIAL_IN
DATASEL
OUT0
OUT1
OUT2
OUT3
OUT4
OUT5
OUT6
OUT7
HSOP28
1
2
3
4
5
6
7
8
9
10
11
12
13
14
VDD
ENABLE
LATCH
CLOCK
SERIAL_IN
DATASEL
OUT0
GND
RESERVED
REXT
SOMODE
ALARM
SERIAL_OUT
OUT15
OUT14
OUT13
OUT12
OUT11
OUT10
OUT9
OUT8
28
27
26
25
24
23
22
21
20
19
18
17
16
15
GND
OUT1
OUT2
OUT3
OUT4
OUT5
OUT6
OUT7
1
2
3
4
5
6
7
28
27
26
25
24
23
22
GND
RESERVED
REXT
SOMODE
ALARM
SERIAL_OUT
OUT15
Thermal Pad
GND
8
9
10
11
12
13
14
OUT14
OUT13
OUT12
OUT11
OUT10
OUT9
OUT8
21
20
19
18
17
16
15
QFN32
OUT9
OUT8
OUT7
OUT6
21
20
19
OUT13
OUT4
OUT10
22
OUT5
OUT11
24
25
23
OUT12
18
17
16
OUT3
26
15
OUT2
OUT14
27
14
OUT1
OUT15
28
13
OUT0
SERIAL_OUT
29
12
DATASEL
ALARM
30
11
SERIAL_IN
SOMODE
31
10
CLOCK
REXT
32
9
LATCH
Thermal Pad
GND
4
5
GND
GND
RESERVED
GND
VDD
16-Bit Constant Current LED Drivers
6
7
8
GND
3
GND
2
ENABLE
1
-2-
Version：A.024
點晶科技股份有限公司
DM133
SILICON TOUCH TECHNOLOGY INC.
Block Diagram
OUT0
ALARM
Thermal
Alarm
OUT15
LED Open Detection
16 bits Constant
Current Driver
Global Current
Controller
16 bits Latch
6 bits Latch
Voltage
Reference
REXT
ENABLE
6bit data
Channel
Selector
10bit data
LATCH
6bit data
DATASEL
SERIAL_IN
Channel
Selector
10 bits Shift Register
6 bits Shift
Register
Serial_out
Selector
CLOCK
SERIAL_OUT
SOMODE
Pin Description
SDIP No.
PIN NAME
FUNCTION
1
VDD
Supply voltage terminal.
2
ENABLE
Input terminal of output enable (active low), all outputs are off when ENABLE
is high.
3
LATCH
Input terminal of data strobe. Data is latched when LATCH is low. And data on
shift register goes through when LATCH is high.
4
CLOCK
Input terminal of a clock for shift register. Data is sampled at the rising edge of
CLOCK.
5
SERIAL_IN
Input terminal of a data shift register.
6
DATASEL
7~22
OUT0~15
Input terminal of a data path selection for output current on/off or global
current adjustment
Output terminals with constant current.
23
SERIAL-OUT Output terminal of a data shift register.
24
ALARM
Output open drain terminal for an alarm function. It will go low as LED
open/short or chip overheated.
25
SOMODE
Input terminal of a data output trigger mode selection
26
REXT
Input terminal of an external resistor. The current flows through the resistor
from REXT to ground will be the reference base current of output sink current.
27
RESERVED Terminal for testing, user should leave this pin open.
28
GND
Ground terminal
16-Bit Constant Current LED Drivers
-3-
Version：A.024
點晶科技股份有限公司
DM133
SILICON TOUCH TECHNOLOGY INC.
Equivalent Circuit of Inputs and Outputs
1. ENABLE, DATASEL terminals
2. LATCH, SOMODE terminals
VDD
VDD
RIN(up)
INPUT
INPUT
RIN(down)
GND
GND
3. CLOCK, SERIAL-IN terminals
4. SERIAL-OUT terminal
VDD
VDD
INPUT
SERIAL_OUT
GND
GND
5. ALARM terminal
VDD
ALARM
GND
16-Bit Constant Current LED Drivers
-4-
Version：A.024
點晶科技股份有限公司
DM133
SILICON TOUCH TECHNOLOGY INC.
Maximum Ratings (Tj(max) = 150°C)
CHARACTERISTIC
Supply Voltage
Input Voltage
SYMBOL
RATING
UNIT
VDD
-0.3 ~ 7.0
V
VIN
-0.3 ~ VDD+0.3
V
Output Current
IOUT
70
mA
Output Voltage
VOUT
-0.3 ~ 17
V
Clock Frequency
fCLK
25
MHz
GND Terminal Current
IGND
Power Dissipation
(4 layer PCB)
Thermal Resistance
1120
mA
2.11 (HSOP-28 : Ta=25°C)
W
1.1 (SSOP-28: Ta=25°C)
W
3.18 (QFN-32 : Ta=25°C)
W
PD
Rth(j-a)
59.1 (HSOP-28)
°C/W
113.3 (SSOP-28)
°C/W
39.3 (QFN-32)
°C/W
Operating Temperature
Topr
-40 ~ 85
°C
Storage Temperature
Tstg
-55 ~ 150
°C
Recommended Operating Condition
CHARACTERISTIC
SYMBOL
CONDITION
MIN.
TYP.
MAX.
UNIT
Supply Voltage
VDD
⎯
3.0
5.0
5.5
V
Output Voltage
VOUT
⎯
⎯
⎯
17
V
IO
OUTn
5
⎯
60
IOH
SERIAL-OUT
⎯
⎯
1.0
IOL
SERIAL-OUT
⎯
⎯
-1.0
VIH
VIL
⎯
⎯
0.8VDD
0.0
⎯
⎯
VDD
0.2VDD
V
Output Current
Input Voltage
mA
LATCH Pulse Width
tw LAT
15
⎯
⎯
ns
CLOCK Pulse Width
tw CLK
15
⎯
⎯
ns
Set-up Time for DATA
tsetup(D)
10
⎯
⎯
ns
Hold Time for DATA
thold(D)
10
⎯
⎯
ns
Set-up Time for LATCH
tsetup(L)
15
⎯
⎯
ns
Single Chip operation
⎯
⎯
25
Cascade operation
(SOMODE=’L’) CL=13pF
⎯
⎯
25
Cascade operation
(SOMODE=‘H’) CL=13pF
⎯
⎯
15
Clock Frequency
fCLK
VDD = 3.3 ~ 5.0 V
16-Bit Constant Current LED Drivers
-5-
MHz
Version：A.024
點晶科技股份有限公司
DM133
SILICON TOUCH TECHNOLOGY INC.
Electrical Characteristics (Typ:VDD = 5.0 V, Ta = 25°C unless otherwise noted)
CHARACTERISTIC
SYMBOL
CONDITION
MIN.
TYP.
MAX.
Input Voltage “H” Level
VIH
⎯
0.8VDD
⎯
VDD
Input Voltage “L” Level
VIL
⎯
GND
⎯
0.2VDD
Output Leakage Current
IOH
VOH = 17 V
⎯
⎯
±1.0
VOL
IOL = 1.0 mA
⎯
⎯
0.3
VOH
IOH = -1.0 mA
VDD-0.3
⎯
⎯
⎯
⎯
±4
%
10.2
11.4
12.6
mA
⎯
±0.1
±0.5
%/V
⎯
±2.0
±4.0
%/V
1.0
LSB
Output Voltage (S - OUT)
Output Current (Bit-Bit)1
IOL1
Output Current
2
(Chip-Chip)
IOL2
Output Voltage Regulation % / VOUT
VOUT = 0.4V, Rrext = 4.8KΩ
VDD=3.3V, (1 channel on)
VOUT = 0.4V, Rrext = 4.8KΩ
VDD=3.3V, (1 channel on)
Rrext = 4.8KΩ,
VOUT = 1V to 3V
Supply Voltage Regulation % / VDD Rrext = 4.8KΩ
Differential Linearity
DLE
Thermal Alarm Detection
Temperature
T(tsd)
LED Open Detection
Voltage
V(od)
Pull-Up Resistor
Pull-Down Resistor
Junction temperature
V
uA
V
140
150
160
℃
⎯
0.3
⎯
V
RIN(up)
⎯
150
300
600
KΩ
RIN(down)
⎯
100
200
400
KΩ
⎯
8
⎯
⎯
8.5
⎯
⎯
11
⎯
⎯
13
⎯
⎯
16
⎯
IDD(off)1
Supply Current “OFF”
-1.0
UNIT
IDD(0ff)2
IDD(off)3
IDD(on)1
Supply Current “ON”
IDD(on)2
Input Signal is static,
Rrext = OPEN, OUT0~15 = off
Input Signal is static,
Rrext = 2.8KΩ, OUT0~15 = off
Input Signal is static,
Rrext = 1.4KΩ, OUT0~15 = off
Input Signal is static,
Rrext = 2.8KΩ, OUT0~15 = on
Input Signal is static,
Rrext = 1.4KΩ, OUT0~15 = on
mA
1
Bit-Bit skew of the IC is defined as the ratio between (any Iout – average Iout) and average Iout, where average
Iout = (Imax + Imin) / 2.
2
Chip-Chip skew is defined the range into which any output current of any IC falls”.
16-Bit Constant Current LED Drivers
-6-
Version：A.024
點晶科技股份有限公司
DM133
SILICON TOUCH TECHNOLOGY INC.
Switching Characteristics (Ta = 25 °C unless otherwise noted)
CHARACTERISTIC
SYMBOL
Propagation ENABLE-OUTn
Delay Time
CONDITION
VDD=5.0V
tpLH
(“L” to “H”) OUTn-Alarm(on)
Rrext=2.4KΩ
tpHL
VL=3.3V
RL=120Ω
(“H” to “L”) OUTn-Alarm(off)
TYP.
MAX.
UNIT
⎯
40
⎯
ns
⎯
70
⎯
ns
⎯
130
⎯
ns
⎯
100
⎯
ns
⎯
50
⎯
ns
⎯
25
⎯
ns
MIN.
TYP.
MAX.
UNIT
⎯
50
⎯
ns
⎯
70
⎯
ns
⎯
160
⎯
ns
⎯
100
⎯
ns
⎯
60
⎯
ns
⎯
25
⎯
ns
VIH=VDD
VIL=GND
Propagation ENABLE-OUTn
Delay Time
MIN.
CL=13pF
Output Current Rise Time
tor
Output Current Fall Time
tof
CHARACTERISTIC
Ralarm=500Ω
SYMBOL
Propagation ENABLE-OUTn
Delay Time
CONDITION
VDD=3.3V
tpLH
(“L” to “H”) OUTn-Alarm(on)
VIH=VDD
VIL=GND
Rrext=2.4KΩ
Propagation ENABLE-OUTn
Delay Time
tpHL
VL=3.3V
RL=120Ω
(“H” to “L”) OUTn-Alarm(off)
CL=13pF
Output Current Rise Time
tor
Output Current Fall Time
tof
Ralarm=500Ω
VDD
Ralarm
VL
500
VDD
Alarm
120
RL
13pF
CL
OUTn
REXT
Rrext
2.4K
16-Bit Constant Current LED Drivers
GND
-7-
Version：A.024
點晶科技股份有限公司
DM133
SILICON TOUCH TECHNOLOGY INC.
Timing Diagram
1. CLOCK-SERIAL-IN, SERIAL-OUT, OUTn
tr
tf
twCLK
CLOCK
SERIAL-IN
90%
50%
10%
tsetup
90%
50%
10%
twCLK
50%
50%
thold
50%
50%
tof
tor
90%
50%
10%
OUTn (current)
90%
50%
10%
tpLH
tpHL
50%
50%
SERIAL-OUT
tpHL
tpLH
2. CLOCK-LATCH
50%
CLOCK
SERIAL-IN
“L” level = DATA HOLD
tw(LAT)
LATCH
50%
50%
tsetup(L)
3. ENABLE-OUTn(current)
ENABLE
50%
50%
tpHL
tpLH
50%
50%
OUTn
16-Bit Constant Current LED Drivers
-8-
Version：A.024
點晶科技股份有限公司
DM133
SILICON TOUCH TECHNOLOGY INC.
Detailed Description
1) Constant Current Output Value Setting
The output current is determined by resistor value multiplying a ratio. The resistor
connected between REXT pin and GND decides the base current output. The resistor
should be located as close to REXT terminal as possible to avoid the noise influence.
The graph below shows the approximate relation between resistor value and output
current value.
In the monochrome or full color LED display cases, for obtaining the uniformity or for
the white balance between modules or ICs, the DM133 offers a more convenient way to
let control system to reach the goal by fine tuning the output current. To further adjust
the current level, the system shall set the DATASEL pin to low and then shift in 6 bits
data code through SERIAL_IN pin. The MSB should be shifted-in first. Take the input
code = (MSB)100101(LSB) for example. The new current is then equal to the base
5
2
0
5
4
3
2
1
0
current multiplied by (2 + 2 + 2 ) (2 + 2 + 2 + 2 + 2 + 2 + 1 ) . The 6 bits data won’t be
changed until the next new data is latched. For some cases, the data only need to be
shifted once after power-on. Note that code: 011111 exists in chip when power on so
that the output current is nearly half amount of the base current.
60.00
Conditions:
55.00
Vout=1.5V, Vrext=1.2V.
50.00
1 channel turned on.
45.00
Iout is approximate to Vrext/Rrext*49.5 (5V)
Vrext/Rrext*46.6 (3.3V)
Iout (mA)
40.00
35.00
30.00
25.00
VDD=5.0V
20.00
15.00
VDD=3.3V
10.00
5.00
0.00
0
2
4
6
8
10
12
14
16
Rext (Kohm)
2) Serial_In Data and Latch
As the DATASEL pin is set high, the SERIAL_IN data will be clocked into the 16 bits
shift register synchronized on the rising edge of CLOCK. And the data ‘1’ represents the
corresponding current output ‘ON’, while the data ‘0’ stands for ‘OFF’. The data will be
transferred into the latch as the LATCH pin goes high. And the data will be latched when
LATCH goes low.
16-Bit Constant Current LED Drivers
-9-
Version：A.024
點晶科技股份有限公司
DM133
SILICON TOUCH TECHNOLOGY INC.
3) Serial_Out Timing Selection
The SERIAL_OUT output timing can be changed by the level of SOMODE. When
SOMODE is set high, data is shifted out on synchronization to the falling edge of
CLOCK, and when SOMODE is set low, data is clocked out to SERIAL_OUT
synchronized on the rising edge of CLOCK.
The graph below depicts the timing of data serial-in and serial-out.
16 Clocks
CLOCK
5V
0V
SERIAL_IN
5V
0V
LATCH
5V
0V
ENABLE
5V
0V
DATASEL
5V
0V
SOMODE
5V
0V
SERIAL_OUT
5V
0V
Previous Data
OUT0
ON
OFF
OUT1
ON
OFF
OUT2
ON
OFF
OUT3
ON
OFF
OUT13
ON
OFF
OUT14
ON
OFF
OUT15
ON
OFF
4) Thermal Alarm
The open-drain ALARM pin will go low when the IC junction temperature is
approximately above 150℃. As the thermal alarm is issued, the system should cool
down the temperature (by lowering the PWM current output, or by turning on the fan
system, …etc.).
The ALARM pin will return to high when the IC junction temperature is approximately
below 100℃ or when the power is turned on again after turned off for several seconds.
Operation in a thermal alarm situation for long time may cause permanent damage to
the IC.
16-Bit Constant Current LED Drivers
-10-
Version：A.024
點晶科技股份有限公司
DM133
SILICON TOUCH TECHNOLOGY INC.
5) LED Open Detection
The DM133 monitors the whole system, but its alarm mechanism won’t burden the
control system until some fault happens. The ALARM pin is used for both signaling the
thermal alarm and LED disconnection. When ALARM is low, either overheating or LED
disconnection occurs. And when ALARM returns to high, either the LED is re-connected
or the temperature is lowered down. Therefore, ENABLE is used to tell which situation
occurs when ALARM goes low.
Assume ENABLE is low and ALARM is low now. By turning ENABLE high, all the
current outputs are off and hence, LED open detection is disabled. Then, if ALARM is
changed to high, LED disconnection must have occurred. On the other hand, if the
ALARM remains low, then, the IC is obviously overheated. The constant current output
can be turned on sequentially to identify which output’s LED is disconnected. Table 1
shows the detectimg operation and the corresponding occurance.
ENABLE
ALARM
OCCURANCE
LowÆHigh
LED Disconnection
LowÆLow
Thermal Alarm
LowÆHigh
LED Number
LED Status
OUTn
Detection Result
ALARM
LED Number
LED Status
OUTn
Detection Result
ALARM
LED Number
LED Status
OUTn
Detection Result
ALARM
1
Good
On
Good
1
Good
On
Good
1
Good
Off
Good
2
3
Not-Good
Good
On
On
Not-Good
Good
Low (case 2, 4)
2
3
Not-Good
Good
On
Off
Not-Good
Good
Low (case 2)
2
3
Not-Good
Good
Off
Off
Good
Good
High
4
Not-Good
On
Not-Good
4
Not-Good
Off
Good
4
Not-Good
Off
Good
Table 1. ALARM pin Output Example
The open-drain ALARM pin will go low when the current output pins are turned on
and below 0.3V. Hence, to prevent the ALARM from going low when LED is in the
normal condition, the supply voltage for LED should be set so that the driver output
voltage goes above 0.4V. Note that it takes 0.2us for the detection function to work
( Ralarm=500Ω ).
16-Bit Constant Current LED Drivers
-11-
Version：A.024
點晶科技股份有限公司
DM133
SILICON TOUCH TECHNOLOGY INC.
There’s a simple procedure to implement the sequence of open detection for a specified
LED module.
SW1
SW2
open
Controller
SW3
SW4
DM133
DM133
Alarm
Alarm
R
Example:
Take the 4x32 LED module as an example. Once the controller received the alarm signal, then
1.
Set ENABLE=H, check that the Valarm remains ‘H’ or ‘L’ to see if any IC is in thermal alarm mode.
2.
Set DATASEL=H and Shift 32 clocks of ‘1’ into the ICs to turn on all 32 outputs, then set
LATCH=H ,ENABLE=L.
3.
Turn on the SW1 and watch the alarm line to see whether its voltage level is from ‘H’ to ‘L’ or not.
Scan all the lines to identify which row has problem.
4.
Once any row has problem.
5.
Shift 32 clocks of ‘0’ into the ICs to turn off all 32 outputs.
6.
Shift an ‘1’ and follow the other 31 ‘0’s to the LED module clock-by-clock, then the controller can
watch the alarm line to see whether its voltage level is from ‘H’ to ‘L’ or not. Then the opened LED
will be identified.
7.
Switch to the next problem row and repeat the step 6.
Follow the above steps, we recognize which LED fails as the controller receives an ‘0’
at 17th clock on the second scan line. Then we can identify the opened LED on the LED
module.
The procedure described above is easy for implementation, the control system
doesn’t need an extra memory to handle the patterns comparison or to switch modes
back and forth.
16-Bit Constant Current LED Drivers
-12-
Version：A.024
點晶科技股份有限公司
DM133
SILICON TOUCH TECHNOLOGY INC.
LED Short Detection
V LED
+
D em u ltip lex er
V sw_
SWnormal/open
SWshort1
SWshort2
SWshort3
R short1
ILED 1
D M 133
D M 133
A larm
A larm
R short2
Controller
ILED 2
D M 133
D M 133
A larm
A larm
R short3
ILED 3
D M 133
D M 133
A larm
A larm
Example:
Consider the following conditions: LED’s (R, G, B) Vf variations are between 1.7V to
4.0V (R:1.7~2.4V, G/B: 3.0~4.0V), VLED=5V, ILED =20mA (R), 15mA (G) and 10mA (B).
In order to detect the short LED, we need to add four components in the LED drive
system: a demultiplexer (SWnormal/open, Swshort) and three Rshorts . And assume the Vsw
is 0.1V in all current condition. The algorithm for detecting the short LED is based on the
forward voltage of the LED in different conditions (normal/short/open circuit).
First, we need to decide the value of Rshort. Two inequalities are follows:
VLED－Vsw－ILED×Rshort－Vf ﹤0.3V
(LED is OK or Open)
(1)
VLED－Vsw－ILED×Rshort
(LED is Short)
(2)
＞0.4V
Let’s take the B LED as an example. From (1), Rshort ＞160Ω (Vf=3.0V) and Rshort ＞
60Ω (Vf=4.0V). Then we choose Rshort ＞160Ω. From (2), we can calculate the Rshort ﹤
450Ω. Finally, we take a proper Rshort ＝ (160+450)/2 ＝ 305Ω. Follow the same steps,
we can get 203Ω for G LED. Note: as ILED is larger than 15mA (ex. ILED =20mA (R)), we
still put the 15mA in the above two equations. Then we’ll get the 247Ω for R LED.
Turn on the SWshort switches one after one. Then follow the LED open detection
procedure; turn on only one LED in the scan process. The Valarm will be “L” as LED is
normal or open. Once the LED is short, The Valarm will be changed to “H”.
16-Bit Constant Current LED Drivers
-13-
Version：A.024
R
點晶科技股份有限公司
DM133
SILICON TOUCH TECHNOLOGY INC.
6) Data Transfer Timing Chart
We assume that the chip’s output current level will be programmed first in order to set
the whole panel global brightness or to set the white balance after power-on sequence
and then the image data will follow.
For example, in the following graph, the data for global current is set to ‘100101’, and
the image data is set to ‘1010101010101010’. At first, we should set the DATASEL low
and then send the current data to SERIAL_IN pin. After 6 clock pulses pass, the data will
be latched by sending a high latch pulse. Then tune the DATASEL to high and send the
image data. The data will be transfered into the shift register after 16 clock pulses and
latched.
If the global current level will still stay the same, then the user only need to shift the
current data once. The data latched will be kept until the next new data shifts in.
5V
0V
5V
0V
5V
0V
5V
0V
DATASEL
SERIAL_IN
CLOCK
LATCH
Data for global current
Data for image
5V
0V
5V
0V
5V
0V
5V
0V
DATASEL
SERIAL_IN
CLOCK
LATCH
7) Thermal Pad
The IC’s thermal pad which is internally connected to the bottom side of chip should
be connected to GND. And, good PCB layout pattern conducted to thermal pad will have
better heat dissipation.
16-Bit Constant Current LED Drivers
-14-
Version：A.024
點晶科技股份有限公司
DM133
SILICON TOUCH TECHNOLOGY INC.
8) Output Current Performance vs. Output Voltage
60.000
60.000
VDD=5.0V
VDD=3.3V
50.000
40.000
40.000
Iout (mA)
Iout (mA)
50.000
30.000
30.000
20.000
20.000
10.000
10.000
0.000
0.000
0
1
2
3
4
5
0
1
2
Vout (V)
3
4
5
Vout (V)
In order to obtain a good constant current output, a suitable output voltage is
necessary. Users can get related information about the minimum output voltage from the
above graph.
9) Power Dissipation
Pd - Ta
3.50
3.00
QFN
Pd (W)
2.50
2.00
HSOP
1.50
1.00
SSOP
0.50
0.00
0
20
40
60
80
100
120
140
160
Ta
Note
As the power dissipation of a semiconductor chip is limited by its package and
ambient temperature, this device requires a maximum output current given by an
operating condition. The maximum allowable power consumption (Pd (max)) of this
device is calculated as follows:
(Tj (junction temperature) (max) - Ta (ambient temperature) )(°C )
Pd (max)(Watt ) =
Rth (°C / Watt )
Based on the Pd (max), the maximum allowable current can be calculated as follows:
Iout = ( Pd – VDD‧IDD) / ( # outputs‧Vo‧Duty )
16-Bit Constant Current LED Drivers
-15-
Version：A.024
點晶科技股份有限公司
DM133
SILICON TOUCH TECHNOLOGY INC.
Package Outline
HSOP28
16-Bit Constant Current LED Drivers
-16-
Version：A.024
點晶科技股份有限公司
DM133
SILICON TOUCH TECHNOLOGY INC.
Package Outline
SSOP28
D
h x 45
E
E1
DETAIL A
C
ZD
θ2
0.25 MM
A
C
e
B
A1
GAUGE PLANE
0.1MM
θ1
DETAIL A
R1
R
L
SEATING PLANE
NOTES: DIMENSION D DOES NOT INCLUDE MODE PROTRUSIONS
OR GATE BURRS.
MOLD PROTRUSIONS AND GATE BURRS SHALL NOT EXCEED
0.006 INCH PER SIDE
SYMBOL
A
A1
A2
B
C
e
D
E
E1
L
h
ZD
R1
R
θ
θ1
θ2
JEDEC
DIMENSION IN MM
DIMENSION IN INCH
MIN. NOM. MAX. MIN. NOM. MAX.
1.35
1.63
1.75
0.053 0.064 0.069
0.1
0.15
0.25
0.004 0.006
0.01
1.5
0.059
0.2
0.3
0.008
0.012
0.18
0.25
0.007
0.01
0.635 BASIC
0.025 BASIC
9.80
9.91
10.01 0.386
0.39
0.394
5.79
5.99
6.20
0.228 0.236 0.244
3.81
3.91
3.99
0.150 0.154 0.157
0.41
0.635
1.27
0.016 0.025
0.05
0.25
0.5
0.01
0.02
0.838 REF
0.033 REF
0.2
0.33
0.008
0.013
0.2
0.008
0
8
0
8
0
0
5
10
15
5
10
15
MO - 137 (AF)
16-Bit Constant Current LED Drivers
-17-
Version：A.024
θ
點晶科技股份有限公司
DM133
SILICON TOUCH TECHNOLOGY INC.
Package Outline
QFN32
TOP VIEW
BOTTOM VIEW
D
D2
0.25 C
25
32
25
24
8
17
24
1
17
8
L
E
E2
e
1
32
0.25 C
9
16
16
9
e
b
0.10
M
C AB
A
0.10 C
A3
A1
SEATING PLANE
SYMBOL
A
A1
A3
b
D
D2
E
E2
e
L
y
MIN.
0.70
0
0.18
1.25
1.25
0.30
DIMENSION
(mm)
NOM.
0.75
0.02
0.25 REF
0.23
5.00 BSC
2.70
5.00 BSC
2.70
0.50 BSC
0.40
0.10
yC
MAX.
0.80
0.05
MIN.
27.6
0
0.30
7.09
3.25
49.21
3.25
49.21
0.50
11.81
DIMENSION
(MIL)
NOM.
29.5
0.79
9.84 REF
9.06
196.85 BSC
106.30
196.85 BSC
106.30
19.69 BSC
15.75
3.94
MAX.
31.5
1.97
11.81
127.95
127.95
19.69
Note: 1.DIMENSIONING AND TOLERANCING CONFORM TO ASME Y145.5M-1994.
2. REFER TO JEDEC STD. MO-220 WHHD-2 ISSUE A
16-Bit Constant Current LED Drivers
-18-
Version：A.024
點晶科技股份有限公司
DM133
SILICON TOUCH TECHNOLOGY INC.
The products listed herein are designed for ordinary electronic applications, such as
electrical appliances, audio-visual equipment, communications devices and so on. Hence,
it is advisable that the devices should not be used in medical instruments, surgical
implants, aerospace machinery, nuclear power control systems, disaster/crime-prevention
equipment and the like. Misusing those products may directly or indirectly endanger
human life, or cause injury and property loss.
Silicon Touch Technology, Inc. will not take any responsibilities regarding the misusage
of the products mentioned above. Anyone who purchases any products described herein
with the above-mentioned intention or with such misused applications should accept full
responsibility and indemnify. Silicon Touch Technology, Inc. and its distributors and all
their officers and employees shall defend jointly and severally against any and all claims
and litigation and all damages, cost and expenses associated with such intention and
manipulation.
16-Bit Constant Current LED Drivers
-19-
Version：A.024