ETC MBI5027 16 bit constant current led sink driver with error detection Datasheet

MBI5027
Preliminary Datasheet
Macroblock
16-bit Constant Current LED Sink Driver
with Error Detection
Features
MBI5027CNS
MBI5016CNS
· Error Detection mode to detect LED open-circuit errors
· 16 constant-current output channels
· Constant output current invariant to load voltage change
· Excellent output current accuracy:
between channels: ±3% (max.), and
between ICs: ±6% (max.)
MBI5027CF
MBI5016CF
· Output current adjusted through an external resistor
· Constant output current range: 5-90 mA
· Fast response of output current, OE (min.): 200 ns
· 25MHz clock frequency
· Schmitt trigger input
· 5V supply voltage
Current Accuracy
Between Channels
Between ICs
< ±3%
< ±6%
MBI5027CP
MBI5016CP
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-
MBI5027
16-bit Constant Current LED Sink Driver with Error Detection
Product Description
MBI5027 succeeds MBI5026 and is designed for LED displays with open-circuit Error Detection
extension. MBI5027 exploits PrecisionDrive™ technology to enhance its output characteristics.
MBI5027 contains a serial buffer and data latches, which convert serial input data into parallel
output format. At MBI5027 output stage, sixteen regulated current ports are designed to provide
uniform and constant current sinks for driving LEDs within a wide range of Vf variations.
While MBI5027 is used in their system design for LED display applications, e.g. LED panels, it
provides users with great flexibility and device performance. 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. MBI5027 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.
MBI5027 exploits the idea of Share-I-O™ technology to extend its performance；in addition,
MBI5027 is backward compatible with MBI5026 in both electrical characteristics and package
aspect. With Share-I-O™ technology, users can, without changing the printed circuit board
originally for MBI5026, let MBI5027 enter a special function mode, an Error Detection mode,
just by setting a sequence of signals on LE(ED1), OE (ED2) and CLK input pins. In the Error
Detection mode, MBI5027 detects the status of individual LED connected to MBI5027. The
status will be saved in a built-in register. Then, a system controller may read, through SDO pin,
the error status from the register to know whether LEDs are properly lit or not. By setting
another sequence of signals on LE(ED1), OE (ED2) and CLK input pins, MBI5027 may resume
to a Normal mode and perform as MBI5026. In Application Information, users can get
detailed ideas about how MBI5027 works in the Error Detection mode.
A Share-I-O™ technique is specifically applied to MBI5027. By means of the Share-I-O™
technique, an additionally effective function, Error Detection, can be added to LED drivers,
however, without any extra pins. Thus, MBI5027 could be a drop-in replacement of MBI5026.
The printed circuit board originally designed for MBI5026 may be also applicable for MBI5027.
For MBI5027, the pin 4, LE(ED1), and the pin 21, OE (ED2), can be acted as different functions
as follows:
Pin
Device Name
MBI5027
Function Description of Pin 4
LE + Error Detection (ED1)
Function Description of Pin 21
OE + Error Detection (ED2)
-2-
April 2003, V0.8-4
MBI5027
16-bit Constant Current LED Sink Driver with Error Detection
Block Diagram
OUT0
OUT1
OUT14
OUT15
IO Regulator
R-EXT
VDD
OE(ED2)
Control Logic
Output Driver & Error Detector
LE(ED1)
16
GND
16-bit Output Latch
CLK
16
16-bit Shift Register
SDI
SDO
16
Terminal Description
Pin Configuration
Pin No.
Pin Name
Function
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
Data strobe input terminal
4
LE(ED1)
Serial data is transferred to the
respective latch when LE(ED1) is high.
The data is latched when LE(ED1)
goes low.
GND
SDI
CLK
LE(ED1)
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(ED2)
OUT15
OUT14
OUT13
OUT12
OUT11
OUT10
OUT9
OUT8
Also, a control signal input for Error
Detection mode (See Timing Diagram)
5~20
OUT0 ~ OUT15 Constant current output terminals
Output enable terminal
21
OE (ED2)
When (active) low, the output drivers
are enabled; when high, all output
drivers are turned OFF (blanked).
Also, a control signal input for Error
Detection 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 resistor for setting up all output
current
5V supply voltage terminal
-3-
April 2003, V0.8-4
MBI5027
16-bit Constant Current LED Sink Driver with Error Detection
Equivalent Circuits of Inputs and Outputs
OE(ED2) terminal
LE(ED1) terminal
VDD
VDD
IN
IN
CLK, SDI terminal
SDO terminal
VDD
VDD
OUT
IN
-4-
April 2003, V0.8-4
MBI5027
16-bit Constant Current LED Sink Driver with Error Detection
Timing Diagram
Normal Mode
N=0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
CLK
SDI
LE(ED2)
OE(ED2)
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
-5-
April 2003, V0.8-4
MBI5027
16-bit Constant Current LED Sink Driver with Error Detection
Entering Error Detection Mode
1
2
3
4
5
CLK
OE(ED2)
1
0
1
1
1
LE(ED1)
0
0
0
1
0
The signal sequence makes MBI5027 enter an Error Detection mode.
Reading Error Status Code
CLK
about 2 μs
OE (ED2)
SDO
Error Status Code
: don’t care
Bit15 Bit14 Bit13 Bit12 Bit11
A system controller can read Error Status codes through SDO pin.
Resuming to Normal Mode
1
2
3
4
5
OE(ED2)
1
0
1
1
1
LE(ED1)
0
0
0
0
0
CLK
Voltage “Low”
The signal sequence makes MBI5027 resume to the Normal mode.
Note:
If users want to know the whole process, that is how to enter the Error Detection mode, read Error
Status codes and resume to the Normal mode, please refer to the contents in Application Information.
-6-
April 2003, V0.8-4
MBI5027
16-bit Constant Current LED Sink Driver with Error Detection
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
-7-
April 2003, V0.8-4
MBI5027
16-bit Constant Current LED Sink Driver with Error Detection
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 (ED2),
LE(ED1) and SDI
CLK, OE (ED2),
LE(ED1) and SDI
0.8VDD
-
VDD+0.3
V
-0.3
-
0.3VDD
V
tw(L)
40
-
-
ns
CLK Pulse Width
tw(CLK)
20
-
-
ns
OE (ED2) Pulse Width
tw(OE)
200
-
-
ns
5
-
-
ns
Output Current
Input Voltage
VIL
LE(ED1) 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(ED1)
tsu(L)
15
-
-
ns
Hold Time for LE(ED1)
th(L)
15
-
-
ns
OE (ED2) Pulse Width
tw(ED2)
2
-
-
us
CLK Pulse Width
tw(CLK)
20
-
-
ns
5
-
-
ns
10
-
-
ns
Setup Time for LE(ED1)
tsu(ED1)
Hold Time for LE(ED1)
th(ED1)
Setup Time for OE (ED2)
tsu(ED2)
5
-
-
ns
Hold Time for OE (ED2)
th(ED2)
10
-
-
ns
Clock Frequency
FCLK
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
Power Dissipation
PD
Error Detection Mode
VDD=4.5~5.5V
-8-
W
April 2003, V0.8-4
MBI5027
16-bit Constant Current LED Sink Driver with Error Detection
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 (ED2)
250
500
800
KΩ
RIN(down)
LE(ED1)
250
500
800
KΩ
Pull-up Resistor
Pull-down Resistor
Open Circuit Error***
Discrimination Voltage
“OFF”
Supply
Current
“ON”
VDS, Th1
When all output ports sink 20mA
simultaneously
1.0
-
-
V
VDS, Th2
When a single output port sinks
20mA
0.8
-
-
V
VDS, Th3
When all output ports sink 50mA
simultaneously
1.2
-
-
V
VDS, Th4
When a single output port sinks
50mA
1.0
-
-
V
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
-
mA
*** To effectively detect the error occurring at the output port, MBI5027 has a built-in current detection
circuit. The current detection circuit will detect the effective current IOUT, effective, and compare the effective
current IOUT, effective, to the target current IOUT, target, defined by Rext. If IOUT, effective, is much less than the
target current IOUT, target, an error flag will be asserted in the built-in Shift Register. The minimum voltage
requirement for such current detection is VDS, Th1, VDS, Th2, VDS, Th3 and VDS, Th4.
-9-
April 2003, V0.8-4
MBI5027
16-bit Constant Current LED Sink Driver with Error Detection
Test Circuit for Electrical Characteristics
IDD
VDD
OE(ED2)
IIH,IIL
CLK
LE(ED1)
IOUT
..
..
OUT0
OUT15
SDI
R - EXT GND
SDO
VIH, VIL
Iref
- 10 -
April 2003, V0.8-4
MBI5027
16-bit Constant Current LED Sink Driver with Error Detection
Switching Characteristics
Characteristic
Symbol
CLK - OUTn
Propagation Delay Time LE(ED1) - OUTn
(“L” to “H”)
OE (ED2) - OUTn
CLK - SDO
Condition
Min.
Typ.
Max.
Unit
tpLH1
-
50
100
ns
tpLH2
-
50
100
ns
tpLH3
-
20
100
ns
15
20
-
ns
-
100
150
ns
-
100
150
ns
-
50
150
ns
15
20
-
ns
20
-
-
ns
20
-
-
ns
tpLH
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(ED1) - OUTn
tpHL2
OE (ED2) - OUTn
tpHL3
CLK - SDO
tpHL
CLK
tw(CLK)
LE(ED1)
tw(L)
OE (ED2)
tw(OE)
200
-
-
ns
Hold Time for LE(ED1)
th(L)
5
-
-
ns
Setup Time for LE(ED1)
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(ED2)
CLK
LE(ED1)
SDI
R - EXT GND
IOUT
..
.
OUT0
OUT15
RL
SDO
CL
Logic input
waveform
VIH = 5V
VL
CL
Iref
VIL = 0V
tr = tf = 10 ns
- 11 -
April 2003, V0.8-4
MBI5027
16-bit Constant Current LED Sink Driver with Error Detection
Timing Waveform
Normal Mode
tW(CLK)
tsu(D)
SDI
50%
50%
CLK
50%
50%
th(D)
50%
SDO
50%
tW(L)
tpLH, tpHL
LE(ED1)
50%
50%
th(L)
OE(ED2)
tsu(L)
LOW = OUTPUTS ENABLED
HIGH = OUTPUT OFF
50%
OUTn
tpLH1, tpHL1
LOW = OUTPUT ON
tpLH2, tpHL2
tW(OE)
50%
OE(ED2)
50%
tpLH3
tpHL3
90%
50%
10%
OUTn
tof
- 12 -
90%
50%
10%
tor
April 2003, V0.8-4
MBI5027
16-bit Constant Current LED Sink Driver with Error Detection
Entering Error Detection Mode
tW(CLK)
50%
50%
CLK
50%
50%
50%
tsu(ED2) th(ED2)
OE(ED2)
50%
50%
tsu(ED1)
LE(ED1)
50%
th(ED1)
50%
2 CLK
Reading Error Status Code
50%
CLK
OE(ED2)
50%
50%
50%
tw(ED2)
- 13 -
April 2003, V0.8-4
MBI5027
16-bit Constant Current LED Sink Driver with Error Detection
Application Information
Constant Current
To design LED displays, MBI5027 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 complete function of the load regulation.
100.00
Iout (mA)
90.00
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)
- 14 -
April 2003, V0.8-4
MBI5027
16-bit Constant Current LED Sink Driver with Error Detection
Adjusting Output Current
The output current of each channel (IOUT) is set by an external resistor, Rext. 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 28.8, approximately,
where Rext, in Ω, is the resistance of the external resistor connected to R-EXT terminal.
The magnitude of current is around 50mA at 360Ω and 25mA at 720Ω.
- 15 -
April 2003, V0.8-4
MBI5027
16-bit Constant Current LED Sink Driver with Error Detection
Entering Error Detection Mode
1
2
3
4
5
CLK
OE(ED2)
1
0
1
1
1
LE(ED1)
0
0
0
1
0
Each time the system controller sends the sequence patterns shown above, MBI5027 can enter
the Error Detection mode. During this phase, the system controller can still send data through
SDI pin.
The state of OE (ED2) and LE(ED1) 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 (ED2) and LE(ED1) are (1, 0), (0, 0), (1, 0), (1, 1) and (1, 0).
Reading Error Status Code
CLK
about
OE(ED2)
SDO
1
0
0
2 μs
0
1
1
1
1
Error Status Code
Bit15 Bit14 Bit13 Bit12 Bit11
Once entering the Error Detection mode, the Error Detection takes place by changing the state
of OE (ED2) from “Voltage High” to “Voltage Low”. The built-in current detection circuit will
detect the effective current IOUT, effective of each output channel, and compare it to the target
current IOUT, target, defined by Rext. If the IOUT, effective , is much less than the target current IOUT, target,
an error status code will be represented as “0” state. During the period of detecting errors, data
cannot be sent into MBI5027 through SDI pin. The “Voltage Low” state of OE (ED2) requires at
least three “0” of which the last “0” should be at least 2μs after the falling edge of OE (ED2).
The occurrence of the last “0” results in the event that MBI5027 saves the error status in the
built-in register. The mentioned state of each “0” is sampled by the rising edge of each CLK.
Before the error status saved in the built-in register is read, the state of OE (ED2) should be
pulled up from “Voltage Low” to “Voltage High”. Then, by sending CLK, MBI5027 shifts out,
through SDO pin, the error status bit by bit.
- 16 -
April 2003, V0.8-4
MBI5027
16-bit Constant Current LED Sink Driver with Error Detection
Resuming to Normal Mode
1
2
3
4
5
OE(ED2)
1
0
1
1
1
LE(ED1)
0
0
0
0
0
CLK
Voltage “Low”
Each time the system controller sends the sequence patterns shown above, MBI5027 can
resume to the Normal mode. During this phase, the system controller can still send data
through SDI pin.
The state of OE (ED2) and LE(ED1) 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 (ED2) and LE(ED1) are (1, 0), (0, 0), (1, 0), (1, 0) and (1, 0).
- 17 -
April 2003, V0.8-4
MBI5027
16-bit Constant Current LED Sink Driver with Error Detection
Timing Chart for Error Detection Mode (An Example)
N x MBI5027 are connected in cascade, ie, SDO, k --> SDI, k+1.
And, all MBI5027 ICs are connected to the same CLK, LE(ED1) and OE (ED2)
signals.
SDO, 2
SDO, 0 SDI, 1
SDO, 1
N-1
SDI, 0
MBI5027, 0
MBI5027, 1
MBI5027, 2
LED j, j = 0… (N x16 –1)
MBI5027, N-2
MBI5027, N-1
SDO, N-1
N-1
CLK
LE(ED1)
OE (ED2)
1
2
3
4
5
th(L)
N x 16 CLK Pulses (Note 1)
3 CLK Pulses Required (Note 2)
N x 16 CLK Pulses (Note 3)
1
2
3
4
5
CLK
SDI, 0
N-1
SDI, 0
N x 16 -1
Don’t Care
2
Serial Data (Note 1)
LE(ED1)
LE(ED1)
OE (ED2)
OE (ED2)
1
0
SDI, 0
Could Be “Don’t Care”
T1 = 2 CLK
T2 = 2µs
T3 (Note 2)
SDO, 0
N-1
SDO, 1
15
14
31
30
N x 16 -2
A
Entering the Error
Detection Mode
B
C
SDO, N-1
N-1
Detecting the Error Status
Sending the Normal Image Data (or Test Data)
Serial Data k, k = 0… (N x 16 –1)
Note 2:
T1 = 2 CLK pluses is required to start the error detection.
Note 1: N x 16 CLK pulses before the
T2 = 2 μs is required to obtain the stable error status result.
next LE shift the valid image data. N x
T3 = the third CLK pulses is required before OE (ED2) goes
16 “1”s are suggested.
voltage high. The rising edge of CLK writes the error status code
back to the MBI5027 built-in shift register.
- 18 -
2
N x 16
1
0
D
Reading Back the Error Status Code
Resuming to the
Normal Mode
Note 3:
The first rising edge of CLK after the rising edge of OE (ED2) starts shifting the Image
Data with LED Error. An LED error will be represented by a “0”, to over write the
original image data “1”. Image Data k, k = 0… (N x 16 –1), = all “1” is suggested.
N x 16 CLK pulses shift all N x 16 error results (Error Status Code) via Node SDO, N
April 2003, V0.8-4
MBI5027
16-bit Constant Current LED Sink Driver with Error Detection
Package Power Dissipation (PD)
The maximum allowable package power dissipation is determined as PD(max) = (Tj – Ta) /
Rth(j-a). When 16 output 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 maximum 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
95%
100%
95%
100%
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 = 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 ℃
90%
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
MBI5027
16-bit Constant Current LED Sink Driver with Error Detection
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
20
Ta = 55°C
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
- 20 -
April 2003, V0.8-4
MBI5027
16-bit Constant Current LED Sink Driver with Error Detection
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
20
Ta = 55°C
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
MBI5027
16-bit Constant Current LED Sink Driver with Error Detection
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)
MBI5027 are designed to operate with V DS ranging from 0.4V to 1.0V considering the package
power dissipating limits. V DS 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.
Resistors or Zener diode can be used in the applications as the following figures.
VLED
VLED
VDROP
VDROP
Vf
Vf
VDS
VDS
MBI5027
MBI5027
- 22 -
April 2003, V0.8-4
MBI5027
16-bit Constant Current LED Sink Driver with Error Detection
Package Outlines
MBI5027CNS Outline Drawing
SDIP-24-P-300-1.78
Units: mm
Weight: 1.11g (typ)
MBI5027CF Outline Drawing
SOP-24-P-300-1.00
Units: mm
Weight: 0.28g (typ)
- 23 -
April 2003, V0.8-4
MBI5027
16-bit Constant Current LED Sink Driver with Error Detection
MBI5027CP Outline Drawing
SSOP24-P-150-0.64
Units: mm
Weight: 0.11g (typ)
- 24 -
April 2003, V0.8-4