ETC MBI5028CNS 16 bit constant current led sink driver with gain control Datasheet

MBI5028
Preliminary Datasheet
Macroblock
16-bit Constant Current LED Sink Driver
with Gain Control
Features
· 16 constant-current output channels
· Output current adjustable through an external resistor
· Output current gain programmable for White Balance
· Constant output current range: 5-90 mA
· Excellent output current accuracy:
between channels: ±3% (max.), and
between ICs: ±6% (max.)
· Constant output current invariant to load voltage change
· Fast response of output current, OE (min.): 200 ns
· 25MHz clock frequency
· Schmitt trigger input
· 5V supply voltage
MBI5028CNS
MBI5016CNS
MBI5016CF
MBI5028CF
MBI5028CP
MBI5016CP
Current Accuracy
Between Channels
Between ICs
< ±3%
< ±6%
Conditions
IOUT = 10 mA ~ 60 mA
ÓMacroblock, Inc. 2003
Floor 6-4, No.18, Pu-Ting Rd., Hsinchu, Taiwan 30077, ROC.
TEL: +886-3-579-0068, FAX: +886-3-579-7534 E-mail: [email protected]
-1-
MBI5028
16-bit Constant Current LED Sink Driver with Gain Control
Product Description
MBI5028 succeeds MBI5026 and is designed for LED displays with Gain Control extension.
MBI5028 exploits PrecisionDrive™ technology to enhance its output characteristics. MBI5028
contains a serial buffer and data latches, which convert serial input data into parallel output
format. At MBI5028 output stage, sixteen regulated current ports are designed to provide
constant current sinks for driving LEDs within a wide range of Vf variations.
MBI5028 provides users with great flexibility and device performance while using MBI5028 in
their LED panel system design. Users may adjust the output current from 5 mA to 90 mA
through an external resistor Rext, which gives users flexibility in controlling the light intensity of
LEDs. MBI5028 guarantees to endure maximum 17V at the output port. The high clock
frequency, 25 MHz, also satisfies the system requirements of high volume data transmission.
MBI5028 also exploits Share-I-O™ technology and is backward compatible with MBI5026 in
both electrical characteristics and package aspect. To utilize the Current Adjust feature with
Share-I-O™ technology, users may not need to change the printed circuit board originally for
MBI5026. To enter a special function mode- Current Adjust mode, users just need to set a
sequence of signals on LE(CA1), OE (CA2) and CLK input pins. Normally, the output current
can be regulated only through an external resistor. In addition, in the Current Adjust mode, the
output current can be software-programmable by a system controller. The system controller
adjusts the output current by sending a 7-bit Current Adjust code to 16-bit Configuration Latch
through MBI5028 SDI pin. The code will be latched and effective to control the output current
regulator. A fine adjustment of the output current could be achieved by a gain ranging from 0.5
to 2 with 128 fine steps. By setting another sequence of signals on LE(CA1), OE (CA2) and
CLK input pins, MBI5028 may resume to a Normal mode and perform as MBI5026. The Shift
Register, with SDI, SDO, and CLK, carries the image data as usual.
A Share-I-O™ technique is specifically applied to MBI5028. By means of the Share-I-O™
technique, an additionally effective function, Current Gain, can be added to LED drivers,
however, without any extra pins. Thus, MBI5028 could be a drop-in replacement of MBI5026.
The printed circuit board originally designed for MBI5026 may be also applicable for MBI5028.
For MBI5028, the pin 4, LE(CA1), and the pin 21, OE (CA2), can be acted as different functions
as follows:
Pin
Device Name
MBI5028
Function Description of Pin 4
LE + Current Adjust (CA1)
Function Description of Pin 21
OE + Current Adjust (CA2)
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April 2003, V0.8-4
MBI5028
16-bit Constant Current LED Sink Driver with Gain Control
Block Diagram
OUT1
OUT0
OUT14
OUT15
IO Regulator
R-EXT
VDD
OE (CA2)
Control Logic
16-bit Output Driver
LE(CA1)
7
GND
16-bit Configuration Latch
16
CLK
16
16-bit Output Latch
16
16-bit Shift Register
SDI
Pin Configuration
Terminal Description
Pin No.
Pin Name
1
GND
Ground terminal for control logic and current sink
2
SDI
Serial-data input to the Shift Register
3
CLK
Clock input terminal for data shift on rising edge
Function
Data strobe input terminal
4
LE(CA1)
Serial data is transferred to the respective latch
when LE(CA1) is high. The data is latched when
LE(CA1) goes low.
Also, a control signal input for Current Adjust
mode (See Timing Diagram)
5~20
SDO
GND
SDI
CLK
LE(CA1)
OUT0
OUT1
OUT2
OUT3
OUT4
OUT5
OUT6
OUT7
1
2
3
4
5
6
7
8
9
10
11
12
24
23
22
21
20
19
18
17
16
15
14
13
VDD
R-EXT
SDO
OE(CA2)
OUT15
OUT14
OUT13
OUT12
OUT11
OUT10
OUT9
OUT8
OUT0 ~ OUT15 Constant current output terminals
Output enable terminal
21
OE (CA2)
When (active) low, the output drivers are enabled;
when high, all output drivers are turned OFF
(blanked).
Also, a second control signal input for Current
Adjust mode (See Timing Diagram)
22
SDO
23
R-EXT
24
VDD
Serial-data output to the following SDI of next
driver IC
Input terminal used to connect an external resister
for setting up all output current
5V supply voltage terminal
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April 2003, V0.8-4
MBI5028
16-bit Constant Current LED Sink Driver with Gain Control
Equivalent Circuits of Inputs and Outputs
OE (CA2) terminal
LE(CA1) terminal
VDD
IN
VDD
IN
CLK, SDI terminal
SDO terminal
VDD
VDD
OUT
IN
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April 2003, V0.8-4
MBI5028
16-bit Constant Current LED Sink Driver with Gain Control
Timing Diagram
Normal Mode
N=0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
CLK
SDI
LE(CA1)
OE (CA2)
OFF
OUT0
ON
OFF
OUT1
ON
OFF
OUT2
ON
OFF
OUT3
ON
OFF
OUT15
ON
SDO
: don’t care
Truth Table (In Normal Mode)
CLK
LE
OE
SDI
OUT0 … OUT 7 … OUT15
SDO
H
L
Dn
Dn ….. Dn - 7 …. Dn - 15
Dn-15
L
L
Dn+1
No Change
Dn-14
H
L
Dn+2
Dn + 2 …. Dn - 5 …. Dn - 13
Dn-13
X
L
Dn+3
Dn + 2 …. Dn - 5 …. Dn - 13
Dn-13
X
H
Dn+3
Off
Dn-13
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April 2003, V0.8-4
MBI5028
16-bit Constant Current LED Sink Driver with Gain Control
Entering Current Adjust Mode
1
2
3
4
5
OE (CA2)
1
0
1
1
1
LE(CA1)
0
0
0
1
0
CLK
The signal sequence makes MBI5028 enter a Current Adjust mode.
Writing Configuration Code
N=0
1
2
3
4
5
12
13
14
15
Bit3
Bit2
Bit1
Bit0
CLK
LE(CA1)
SDI
16-Bit Configuration Code
Bit15 Bit14 Bit13 Bit12 Bit11 Bit10
Note:
Pin OE (CA2) always enables the output port no matter MBI5028 enters a Current Adjust mode or not.
When entering the Current Adjust mode, by sending the positive pulse of LE(CA1), the content of the
Shift Register, a Current Adjust code, will be written to the 16-Bit Configuration Latch.
Resuming to Normal Mode
1
2
3
4
5
OE (CA2)
1
0
1
1
1
LE(CA1)
0
0
0
0
0
CLK
Voltage “Low”
The signal sequence makes MBI5028 resume to a Normal mode.
Note:
If users want to know the whole process, that is how to enter a Current Adjust mode, write Current
Adjust codes and resume to a Normal mode, please refer to the contents in Application Information.
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April 2003, V0.8-4
MBI5028
16-bit Constant Current LED Sink Driver with Gain Control
Maximum Ratings
Characteristic
Symbol
Rating
Unit
Supply Voltage
VDD
0~7.0
V
Input Voltage
VIN
-0.4~VDD + 0.4
V
Output Current
IOUT
+90
mA
Output Voltage
VDS
-0.5~+20.0
V
Clock Frequency
FCLK
25
MHz
GND Terminal Current
IGND
1440
mA
CNS – type
Power Dissipation
(On PCB, Ta=25°C)
Thermal Resistance
(On PCB, Ta=25°C)
1.52
PD
CF – type
1.30
CP – type
1.11
CNS – type
82
Rth(j-a)
CF – type
CP – type
96
W
°C/W
112
Operating Temperature
Topr
-40~+85
°C
Storage Temperature
Tstg
-55~+150
°C
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April 2003, V0.8-4
MBI5028
16-bit Constant Current LED Sink Driver with Gain Control
Recommended Operating Conditions
Characteristic
Symbol
Condition
Min.
Typ.
Max.
Unit
Supply Voltage
VDD
-
4.5
5.0
5.5
V
Output Voltage
VDS
OUT0 ~ OUT15
-
-
17.0
V
IOUT
DC Test Circuit
5
-
60
mA
IOH
SDO
-
-
-1.0
mA
IOL
SDO
-
-
1.0
mA
VIH
CLK, OE (CA2), LE(CA1)
and SDI
CLK, OE (CA2), LE(CA1)
and SDI
0.8VDD
-
VDD+0.3
V
-0.3
-
0.3VDD
V
tw(L)
40
-
-
ns
OE (CA2) Pulse Width
tw(OE)
200
-
-
ns
CLK Pulse Width
tw(CLK)
20
-
-
ns
5
-
-
ns
Output Current
Input Voltage
VIL
LE(CA1) Pulse Width
Normal Mode
VDD=4.5~5.5V
Setup Time for SDI
tsu(D)
Hold Time for SDI
th(D)
10
-
-
ns
Setup Time for LE(CA1)
tsu(L)
15
-
-
ns
Hold Time for LE(CA1)
th(L)
15
-
-
ns
CLK Pulse Width
tw(CLK)
20
-
-
ns
Setup Time for LE(CA1)
tsu(CA1)
5
-
-
ns
10
-
-
ns
Current Adjust Mode
VDD=4.5~5.5V
Hold Time for LE(CA1)
th(CA1)
Setup Time for OE (CA2)
tsu(CA2)
5
-
-
ns
Hold Time for OE (CA2)
th(CA2)
10
-
-
ns
Cascade Operation
-
-
25.0
MHz
Ta=85°C (CNS type)
-
-
0.79
Ta=85°C (CF type)
-
-
0.67
Ta=85°C (CP type)
-
-
0.57
Clock Frequency
Power Dissipation
FCLK
PD
-8-
W
April 2003, V0.8-4
MBI5028
16-bit Constant Current LED Sink Driver with Gain Control
Electrical Characteristics
Characteristic
Input Voltage
Symbol
Condition
Min.
Typ.
Max.
Unit
“H” level
VIH
Ta = -40~85ºC
0.8VDD
-
VDD
V
“L” level
VIL
Ta = -40~85ºC
GND
-
0.3VDD
V
IOH
VOH=17.0V
-
-
0.5
μA
VOL
IOL=+1.0mA
-
-
0.4
V
VOH
IOH=-1.0mA
4.6
-
-
V
Output Leakage Current
Output
Voltage
SDO
Output Current 1
IOUT1
VDS=0.6V
Rext=720 Ω
-
25.0
-
mA
Current Skew
dIOUT1
IOL=25mA
VDS=0.6V
Rext=720 Ω
-
±1
±3
%
Output Current 2
IOUT2
VDS=0.8V
Rext=360 Ω
-
50.0
-
mA
Current Skew
dIOUT2
IOL=50mA
VDS=0.8V
Rext=360 Ω
-
±1
±3
%
Output Current vs.
Output Voltage Regulation
%/dVDS
VDS within 1.0V and 3.0V
-
±0.1
-
%/V
Output Current vs.
Supply Voltage Regulation
%/dVDD
VDD within 4.5V and 5.5V
-
±1
-
%/V
RIN(up)
OE (CA2)
250
500
800
KΩ
RIN(down)
LE(CA1)
250
500
800
KΩ
IDD(off) 1
Rext=Open, OUT0 ~ OUT15 =Off
-
9
-
IDD(off) 2
Rext=720 Ω, OUT0 ~ OUT15 =Off
-
11
-
IDD(off) 3
Rext=360 Ω, OUT0 ~ OUT15 =Off
-
14
-
IDD(on) 1
Rext=720 Ω, OUT0 ~ OUT15 =On
-
11
-
IDD(on) 2
Rext=360 Ω, OUT0 ~ OUT15 =On
-
14
-
Pull-up Resister
Pull-down Resister
“OFF”
Supply
Current
“ON”
mA
Test Circuit for Electrical Characteristics
IDD
VDD
OE(CA2)
IIH, IIL
CLK
LE(CA1)
IOUT
..
..
OUT0
OUT15
SDI
R - EXT GND
SDO
VIH, VIL
Iref
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April 2003, V0.8-4
MBI5028
16-bit Constant Current LED Sink Driver with Gain Control
Switching Characteristics
Characteristic
Propagation Delay Time
(“L” to “H”)
Symbol
Condition
Min.
Typ.
Max.
Unit
CLK - OUTn
tpLH1
-
50
100
ns
LE(CA1) - OUTn
tpLH2
-
50
100
ns
OE (CA2)- OUTn
tpLH3
-
20
100
ns
CLK - SDO
tpLH
15
20
-
ns
-
100
150
ns
-
100
150
ns
-
50
150
ns
15
20
-
ns
20
-
-
ns
20
-
-
ns
VDD=5.0 V
VDS=0.8 V
VIH=VDD
VIL=GND
Rext=300 Ω
VL=4.0 V
RL=52 Ω
CL=10 pF
CLK - OUTn
tpHL1
LE(CA1) - OUTn
tpHL2
OE (CA2)- OUTn
tpHL3
CLK - SDO
tpHL
CLK
tw(CLK)
LE(CA1)
tw(L)
OE (CA2)
tw(OE)
200
-
-
ns
Hold Time for LE(CA1)
th(L)
5
-
-
ns
Setup Time for LE(CA1)
tsu(L)
5
-
-
ns
Maximum CLK Rise Time
tr**
-
-
500
ns
Maximum CLK Fall Time
tf**
-
-
500
ns
Output Rise Time of Iout
tor
-
70
200
ns
Output Fall Time of Iout
tof
-
40
120
ns
Propagation Delay Time
(“H” to “L”)
Pulse Width
**If the devices are connected in cascade and tr or tf is large, it may be critical to achieve the timing required for
data transfer between two cascaded devices.
Test Circuit for Switching Characteristics
IDD
VIH, VIL
Function
Generator
VDD
OE(CA2)
CLK
LE(CA1)
IOUT
..
..
OUT0
OUT15
RL
SDI
R - EXT GND
SDO
CL
Logic input
waveform
VIH = 5V
VL
CL
Iref
VIL = 0V
tr = tf = 10 ns
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April 2003, V0.8-4
MBI5028
16-bit Constant Current LED Sink Driver with Gain Control
Timing Waveform
Normal Mode
tW(CLK)
tsu(D)
SDI
50%
50%
CLK
50%
50%
th(D)
50%
SDO
50%
tW(L)
tpLH, tpHL
LE(CA1)
50%
50%
th(L)
OE (CA2)
tsu(L)
LOW = OUTPUTS ENABLED
HIGH = OUTPUT OFF
50%
OUTn
tpLH1, tpHL1
LOW = OUTPUT ON
tpLH2, tpHL2
tW(OE)
50%
OE (CA2)
50%
tpLH3
tpHL3
90%
50%
10%
OUTn
tof
- 11 -
90%
50%
10%
tor
April 2003, V0.8-4
MBI5028
16-bit Constant Current LED Sink Driver with Gain Control
Entering Current Adjust Mode
tW(CLK)
50%
50%
CLK
50%
50%
50%
tsu(CA2) th(CA2)
OE (CA2)
50%
50%
tsu(CA1)
LE(CA1)
50%
th(CA1)
50%
2 CLK
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April 2003, V0.8-4
MBI5028
16-bit Constant Current LED Sink Driver with Gain Control
Application Information
Constant Current
To design LED displays, MBI5028 provides nearly no variations in current from channel to
channel and from IC to IC. This can be achieved by:
1) The maximum current variation between channels is less than ±3%, and that between ICs is
less than ±6%.
2) In addition, the current characteristic of output stage is flat and users can refer to the figure
as shown below. The output current can be kept constant regardless of the variations of LED
forward voltages (Vf). This performs as a perfection of load regulation.
100.00
90.00
Iout (mA)
80.00
70.00
60.00
50.00
40.00
30.00
20.00
10.00
0.00
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
1.1
1.2
1.3
1.4
1.5
2
2.5
VDS (V)
- 13 -
April 2003, V0.8-4
MBI5028
16-bit Constant Current LED Sink Driver with Gain Control
Adjusting Output Current
The output current of each channel (IOUT) is set by an external resistor, Rext. After a power-on
status, the relationship between Iout and Rext is shown in the following figure.
IOUT (mA)
100
90
80
70
VDS = 1.0V
60
50
40
30
20
10
0
0
500
1000
1500
2000
2500
3000
3500
4000
Resistance of the external resistor, Rext, in Ω
Also, the output current in milliamps can be calculated from the equation:
IOUT is (625/ Rext) x 14.4 x G, approximately,
where Rext, in Ω, is the resistance of the external resistor connected to R-EXT terminal.
Conceptually, G is the digital current gain.
After a power-on status, the default value of G is 1.984.
Based on IOUT = (625/ Rext) x 14.4 x G, thus, IOUT is (625/ Rext) x 28.8
The magnitude of current is around 50mA at 360Ω and 25mA at 720Ω.
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April 2003, V0.8-4
MBI5028
16-bit Constant Current LED Sink Driver with Gain Control
Entering Current Adjust Mode
1
2
3
4
5
OE (CA2)
1
0
1
1
1
LE(CA1)
0
0
0
1
0
CLK
Each time the system controller sends the sequence patterns shown above, MBI5028 can enter
the Current Adjust mode. During this phase, the system controller can still send data through
SDI pin.
The state of OE (CA2) and LE(CA1) is sampled by the rising edge of each CLK. We use “0”
and “1” to represent the state of “Voltage Low” and “Voltage High” respectively. The states of
the successive five OE (CA2) and LE(CA1) are (1, 0), (0, 0), (1, 0), (1, 1) and (1, 0).
Writing Configuration Code
N=0
1
2
3
4
5
12
13
14
15
Bit3
Bit2
Bit1
Bit0
CLK
LE(CA1)
SDI
16-Bit Configuration Code
Bit15 Bit14 Bit13 Bit12 Bit11 Bit10
: don’t care
After entering the Current Adjust mode, the system controller sends a 7-bit Current Adjust code
to 16-bit Shift Register through MBI5028 SDI pin. Then sending LE(CA1) will transfer the
contents in the Shift Register to a 16-bit Configuration Latch rather than the 16-bit Output Latch
in a Normal mode. The 7-bit Current Adjust code in the Configuration Latch will directly affect
the IO Regulator by a gain, G. The output current resulted by the gain values will be then defined
as: (625/ Rext) x 14.4 x G
- 15 -
April 2003, V0.8-4
MBI5028
16-bit Constant Current LED Sink Driver with Gain Control
Current Gain
…
Gain =
1+(63/64)
64 steps
….
….
Gain = 1
….
….
64 steps
Gain = 1/2
(1,0,0,0,0,0,0)
(0,0,0,0,0,0,0)
(1,1,1,1,1,1,1)
(0,0,0,0,0,0,1)
(0,0,0,0,0,1,0)
16-Bit Configuration Code
Meaning
Default
Value
Bit 0 Bit 1 Bit 2 Bit 3 Bit 4 Bit 5 Bit 6 Bit 7
HC CC0 CC1 CC2 CC3 CC4 CC5
-
1
1
1
1
1
1
1
Bit 8
-
Bit 9 Bit 10 Bit 11 Bit 12 Bit 13 Bit 14 Bit 15
-
-
-
-
-
-
-
7-bit Current Adjust Code
Binary Representation of the Current Adjust Code =｛HC, CC〔0:5〕｝
Gain, G = (1 + HC) x (1 + D/64)/2
where HC is 1 or 0 (HC=0 : Low current band; HC=1 : High current band) and
D = CC0 x 25+ CC1 x 24+ CC2 x 23+ CC3 x 22+ CC4 x 21+ CC5 x 20;
So, the Current Adjust Code is a floating number with one bit exponent HC and 6-bit mantissa.
- 16 -
April 2003, V0.8-4
MBI5028
16-bit Constant Current LED Sink Driver with Gain Control
For example,
when the Current Adjust Code is (1,1,1,1,1,1,1)
Gain, G = (1+1) x (1+ 63/64)/2 = 1.984
when the Current Adjust Code is (1,0,0,0,0,0,0)
Gain, G = (1+1) x (1+ 0/64)/2 = 1
when the Current Adjust Code is (0,0,0,0,0,0,0)
Gain, G = (1+0) x (1+ 0/64)/2 = 0.5
After power on, the default value of Current Adjust Code is (1,1,1,1,1,1,1). Thus, G is 1.984.
Typically, the output current resulted by the digital current gain, G, is shown as the figure below.
Iout vs. Gain (Rext = 720Ω)
30
Iout (mA)
25
20
15
10
5
0
0.5
0.65
0.8
0.95
1.1
1.25
1.4
1.55
1.7
1.85
2
Gain
Resuming to Normal Mode
1
2
3
4
5
OE (CA2)
1
0
1
1
1
LE(CA1)
0
0
0
0
0
CLK
Voltage “Low”
Each time the system controller sends the sequence patterns shown above, MBI5028 can
resume to a Normal mode. During this phase, the system controller can still send data through
SDI pin.
The state of OE (CA2) and LE(CA1) is sampled by the rising edge of each CLK. We use “0”
and “1” to represent the state of “Voltage Low” and “Voltage High” respectively. The states of
the successive five OE (CA2) and LE(CA1) are (1, 0), (0, 0), (1, 0), (1, 0) and (1, 0).
After resuming to the Normal mode, the Shift Register is again merely used for conveying the
image data sent from the system controller. The gain will always be effective until power off or
the Configuration Latch is re-written.
- 17 -
April 2003, V0.8-4
MBI5028
16-bit Constant Current LED Sink Driver with Gain Control
Timing Chart for Current Adjust Mode (An Example)
N x MBI5028 are connected in cascade, ie, SDO, k --> SDI, k+1.
And, all MBI5028 ICs are connected to the same CLK, LE(CA1) and
OE (CA2) sources.
SDO, 0 SDI, 1
SDO, 1
SDI, 0
CLK
LE(CA1)
OE (CA2)
1 2 3
4
MBI5028, 1
MBI5028, 0
SDO, 2
SDO, N-1
MBI5028, N-2
MBI5028, 2
5
MBI5028, N-1
1
N x 16 CLK Pulses (Note 1)
2
3
4
5
CLK
SDI, 0
-
-
-
-
-
-
-
CC5 CC4 CC3 CC2 CC1 CC0
CC HC
-
-
-
-
-
-
-
-
CC5 CC4 CC3 CC2 CC1 CC0 HC
-
Configuration Codes (Note 1) (Note2)
For MBI5028, 0
For MBI5028, N -1
LE(CA1)
OE (CA2)
LE(CA1) Pulse (Note 3)
Writing the Configuration Codes,
Code k, k = 0… (N x 16 –1)
A
Entering Current
Adjust Mode
B
Note 1: N x 16 CLK pulses before
the next LE(CA1) shift the
configuration codes. N 16-bit
Configuration Codes are required,
although only 7 bits are significant.
C
Note 2:
Gain G = (1+ HC) x (1 + D/64)/2
D = CC0 x 25+ CC1 x 24 + CC2 x 23 + CC3 x 22 +
CC4 x 21 + CC5 x 20 .
- 18 -
Note 3:
The LE(CA1) pulse writes the Configuration Codes
to each MBI5028.
Resuming to Normal
Mode
April 2003, V0.8-4
MBI5028
16-bit Constant Current LED Sink Driver with Gain Control
Package Power Dissipation (PD)
The maximum allowable package power dissipation is determined as PD(max) = (Tj – Ta) /
Rth(j-a). When 16 channels are turned on simultaneously, the actual package power dissipation
is PD(act) = (IDD x VDD) + (IOUT x Duty x VDS x 16). Therefore, to keep PD(act) ≤ PD(max), the
allowable output current as a function of duty cycle is:
IOUT = { [ (Tj – Ta) / Rth(j-a) ] – (IDD x VDD) } / VDS / Duty / 16,
where Tj = 150°C.
(A) Iout = 90mA, VDS = 1.0V, 16 output channels active
For CNS type package, the thermal resistance is Rth(j-a) = 82 (°C/W)
Ta = 25°C
Ta = 55°C
90%
95%
100%
90%
95%
100%
85%
80%
75%
70%
65%
60%
55%
50%
45%
40%
35%
30%
25%
20%
15%
10%
Ta = 85°C
5%
Iout (mA)
Iout vs. Duty Cycle at Rth = 82 (°C/W)
100
90
80
70
60
50
40
30
20
10
0
Duty Cycle
For CF type package, the thermal resistance is Rth(j-a) = 96 (°C/W)
100
90
80
70
60
50
40
30
20
10
0
Ta = 25 ℃
Ta = 55 ℃
85%
80%
75%
70%
65%
60%
55%
50%
45%
40%
35%
30%
25%
20%
15%
10%
Ta = 85 ℃
5%
Iout (mA)
Iout vs. Duty Cycle at Rth = 96 (°C/W)
Duty Cycle
- 19 -
April 2003, V0.8-4
MBI5028
16-bit Constant Current LED Sink Driver with Gain Control
For CP type package, the thermal resistance is Rth(j-a) = 112 (°C/W)
100
90
80
70
60
50
40
30
20
10
0
Ta = 25°C
Ta = 55°C
100%
95%
90%
85%
80%
75%
70%
65%
60%
55%
50%
45%
40%
35%
30%
25%
20%
15%
10%
Ta = 85°C
5%
Iout (mA)
Iout vs. Duty Cycle at Rth = 112 (°C/W)
Duty Cycle
(B) Iout = 60mA, VDS = 0.8V, 16 output channels active
For CNS type package, the thermal resistance is Rth(j-a) = 82 (°C/W)
Iout vs. Duty Cycle at Rth = 82 (°C/W)
70
60
40
Ta = 25°C
30
Ta = 55°C
20
Ta = 85°C
10
100%
95%
90%
85%
80%
75%
70%
65%
60%
55%
50%
45%
40%
35%
30%
25%
20%
15%
10%
0
5%
Iout (mA)
50
Duty Cycle
- 20 -
April 2003, V0.8-4
MBI5028
16-bit Constant Current LED Sink Driver with Gain Control
For CF type package, the thermal resistance is Rth(j-a) = 96 (°C/W)
Iout vs. Duty Cycle at Rth = 96 (°C/W)
70
60
Iout (mA)
50
Ta = 25°C
40
30
Ta = 55°C
20
Ta = 85°C
10
100%
95%
90%
85%
80%
75%
70%
65%
60%
55%
50%
45%
40%
35%
30%
25%
20%
15%
5%
10%
0
Duty Cycle
For CP type package, the thermal resistance is Rth(j-a) = 112 (°C/W)
Iout vs. Duty Cycle at Rth = 112 (°C/W)
70
60
40
Ta = 25°C
30
Ta = 55°C
20
10
Ta = 85°C
100%
95%
90%
85%
80%
75%
70%
65%
60%
55%
50%
45%
40%
35%
30%
25%
20%
15%
10%
0
5%
Iout (mA)
50
Duty Cycle
- 21 -
April 2003, V0.8-4
MBI5028
16-bit Constant Current LED Sink Driver with Gain Control
The maximum power dissipation, PD(max) = (Tj-Ta) / Rth(j-a) , decreases as the ambient
temperature increases.
Max. Power Dissipation at Various Ambient Temperature
1.6
Power Dissipation
1.4
1.2
1
CNS Type: Rth = 82
0.8
CF Type: Rth = 96
0.6
CP Type: Rth = 112
0.4
0.2
0
-40
-30
-20
-10
0
10
20
30
40
50
60
70
80
90
Ambient Temperature
Load Supply Voltage (VLED)
MBI5028 are designed to operate with VDS ranging from 0.4V to 1.0V considering the package
power dissipating limits. VDS may be higher enough to make PD(act) > PD(max) when VLED = 5V
and VDS = VLED – Vf, in which VLED is the load supply voltage. In this case, it is recommended to
use the lowest possible supply voltage or to set an external voltage reducer (VDROP).
A voltage reducer lets VDS = (VLED – Vf) – VDROP.
Resisters, or Zener diode can be used in the applications as the following figures.
VLED
VLED
VDROP
VDROP
Vf
Vf
VDS
VDS
MBI5028
MBI5028
- 22 -
April 2003, V0.8-4
MBI5028
16-bit Constant Current LED Sink Driver with Gain Control
Package Outlines
MBI5028CNS Outline Drawing
SDIP-24-P-300-1.78
Units: mm
Weight: 1.11g (typ)
MBI5028CF Outline Drawing
SOP-24-P-300-1.00
Units: mm
Weight: 0.28g (typ)
- 23 -
April 2003, V0.8-4
MBI5028
16-bit Constant Current LED Sink Driver with Gain Control
MBI5028CP Outline Drawing
SSOP24-P-150-0.64
Units: mm
Weight: 0.11g (typ)
- 24 -
April 2003, V0.8-4