MBI5028 [ETC]

16 BIT CONSTANT CURRENT LED SINK DRIVER WITH GAIN CONTROL; 16位LED恒流带增益控制驱动器


型号：	MBI5028
厂家：	ETC
描述：	16 BIT CONSTANT CURRENT LED SINK DRIVER WITH GAIN CONTROL 16位LED恒流带增益控制驱动器驱动器
文件：	总24页 (文件大小：468K)
中文：	中文翻译
下载：	下载PDF数据表文档文件

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.)

MBI5028CNS

MBI5016CNS

MBI5016CF

MBI5028CF

· 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

MBI5028CP

MBI5016CP

Current Accuracy

Conditions

I_OUT= 10 mA ~ 60 mA

Between Channels

Between ICs

< ±3%

< ±6%

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: info@mblock.com.tw

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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 R_ext, 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

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:

Device Name

MBI5028

Function Description of Pin 4

LE + Current Adjust (CA1)

OE + Current Adjust (CA2)

Function Description of Pin 21

April 2003, V0.8-4

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MBI5028

16-bit Constant Current LED Sink Driver with Gain Control

Block Diagram

OUT15

OUT14

OUT1

OUT0

R-EXT

I_ORegulator

VDD

(CA2)

Control Logic

16-bit Output Driver

LE(CA1)

GND

16-bit Configuration Latch

16-bit Output Latch

CLK

SDI

16-bit Shift Register

SDO

Pin Configuration

Terminal Description

Pin No.

Pin Name

Function

VDD

R-EXT

SDO

GND

SDI

CLK

GND

Ground terminal for control logic and current sink

SDI

Serial-data input to the Shift Register

Clock input terminal for data shift on rising edge

Data strobe input terminal

LE(CA1)

OE(CA2)

OUT15

OUT14

OUT13

OUT12

OUT11

OUT10

OUT9

OUT0

OUT1

OUT2

OUT3

OUT4

OUT5

OUT6

OUT7

CLK

Serial data is transferred to the respective latch

when LE(CA1) is high. The data is latched when

LE(CA1) goes low.

LE(CA1)

OUT8

Also, a control signal input for Current Adjust

mode (See Timing Diagram)

OUT0 ~OUT15

5~20

Constant current output terminals

Output enable terminal

When (active) low, the output drivers are enabled;

when high, all output drivers are turned OFF

(blanked).

OE (CA2)

Also, a second control signal input for Current

Adjust mode (See Timing Diagram)

Serial-data output to the following SDI of next

driver IC

SDO

Input terminal used to connect an external resister

for setting up all output current

R-EXT

VDD

5V supply voltage terminal

April 2003, V0.8-4

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MBI5028

16-bit Constant Current LED Sink Driver with Gain Control

Equivalent Circuits of Inputs and Outputs

(CA2) terminal

LE(CA1) terminal

VDD

CLK, SDI terminal

SDO terminal

VDD

OUT

April 2003, V0.8-4

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MBI5028

16-bit Constant Current LED Sink Driver with Gain Control

Timing Diagram

Normal Mode

N = 0

10 11 12

14 15

CLK

SDI

LE(CA1)

OE (CA2)

OFF

OUT0

OFF

OUT1

OFF

OUT2

OUT3

OFF

OUT15

SDO

: don’t care

Truth Table (In Normal Mode)

OUT0 … OUT 7… OUT15

Dn ….. Dn - 7 ….Dn - 15

CLK

SDI

D_n

SDO

D_n-15

D_n-14

D_n-13

D_n+1

D_n+2

D_n+3

No Change

Dn + 2 ….Dn - 5 ….Dn - 13

Off

April 2003, V0.8-4

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MBI5028

16-bit Constant Current LED Sink Driver with Gain Control

Entering Current Adjust Mode

CLK

(CA2)

LE(CA1)

The signal sequence makes MBI5028 enter a Current Adjust mode.

Writing Configuration Code

N = 0

14 15

CLK

LE(CA1)

SDI

16-Bit Configuration Code

Bit15

Bit14 Bit13 Bit12 Bit11 Bit10

Bit3 Bit2 Bit1

Bit0

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

CLK

(CA2)

Voltage “Low”

LE(CA1)

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.

April 2003, V0.8-4

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MBI5028

16-bit Constant Current LED Sink Driver with Gain Control

Maximum Ratings

Characteristic

Symbol

V_DD

Rating

0~7.0

-0.4~V_DD+ 0.4

+90

Unit

Supply Voltage

Input Voltage

V_IN

Output Current

Output Voltage

Clock Frequency

GND Terminal Current

I_OUT

V_DS

-0.5~+20.0

F_CLK

I_GND

MHz

1440

CNS – type

CF – type

CP – type

CNS – type

CF – type

CP – type

1.52

Power Dissipation

(On PCB, Ta=25°C)

P_D

1.30

1.11

Thermal Resistance

(On PCB, Ta=25°C)

R_th(j-a)

°C/W

112

Operating Temperature

Storage Temperature

T_opr

T_stg

-40~+85

-55~+150

°C

April 2003, V0.8-4

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MBI5028

16-bit Constant Current LED Sink Driver with Gain Control

Recommended Operating Conditions

Characteristic

Supply Voltage

Symbol

Condition

Min.

Typ.

Max.

Unit

V_DD

V_DS

I_OUT

I_OH

4.5

5.0

5.5

17.0

Output Voltage

OUT0~OUT15

DC Test Circuit

Output Current

SDO

-1.0

1.0

I_OL

CLK, OE (CA2), LE(CA1)

and SDI

V_IH

V_IL

0.8V_DD

-0.3

V_DD+0.3

0.3V_DD

Input Voltage

CLK, OE (CA2), LE(CA1)

and SDI

200

t_w(L)

t_w(OE)

t_w(CLK)

LE(CA1) Pulse Width

OE (CA2) Pulse Width

CLK Pulse Width

Normal Mode

V_DD=4.5~5.5V

Setup Time for SDI

su(D)

Hold Time for SDI

h(D)

Setup Time for LE(CA1)

Hold Time for LE(CA1)

CLK Pulse Width

su(L)

h(L)

t_w(CLK)

Setup Time for LE(CA1)

Hold Time for LE(CA1)

Setup Time for OE (CA2)

Hold Time for OE (CA2)

Clock Frequency

su(CA1)

Current Adjust Mode

V_DD=4.5~5.5V

h(CA1)

su(CA2)

h(CA2)

F_CLK

Cascade Operation

Ta=85°C (CNS type)

Ta=85°C (CF type)

Ta=85°C (CP type)

25.0

0.79

0.67

0.57

MHz

Power Dissipation

P_D

April 2003, V0.8-4

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MBI5028

16-bit Constant Current LED Sink Driver with Gain Control

Electrical Characteristics

Characteristic

Symbol

Condition

Min.

Typ.

Max.

Unit

“H” level

“L” level

V_IH

V_IL

Ta = -40~85ºC

0.8V_DD

GND

V_DD

Input Voltage

0.3V_DD

Output Leakage Current

I_OH

V_OH=17.0V

0.5

μA

V_OL

V_OH

I_OL=+1.0mA

I_OH=-1.0mA

0.4

Output

SDO

Voltage

4.6

Output Current 1

Current Skew

I_OUT1

dI_OUT1

I_OUT2

V_DS=0.6V

R_ext=720 Ω

R_ext=360 Ω

25.0

±1

I_OL=25mA

V_DS=0.6V

±3

V_DS=0.8V

50.0

±1

Output Current 2

Current Skew

I_OL=50mA

V_DS=0.8V

dI_OUT2

±3

Output Current vs.

Output Voltage Regulation

%/dV_DS

%/dV_DD

V_DSwithin 1.0V and 3.0V

V_DDwithin 4.5V and 5.5V

±0.1

±1

% / V

Output Current vs.

Supply Voltage Regulation

Pull-up Resister

R_IN(up)

R_IN(down)

I_DD(off) 1

I_DD(off) 2

I_DD(off) 3

I_DD(on) 1

I_DD(on) 2

250

500

800

KΩ

OE (CA2)

Pull-down Resister

250

800

LE(CA1)

R_ext=Open, OUT0~OUT15 =Off

R_ext=720 Ω, OUT0 ~OUT15 =Off

R_ext=360 Ω, OUT0 ~OUT15 =Off

R_ext=720 Ω, OUT0~OUT15 =On

R_ext=360 Ω, OUT0~OUT15 =On

“OFF”

Supply

Current

“ON”

Test Circuit for Electrical Characteristics

IDD

IOUT

VDD

OUT0

OE(CA2)

IIH,IIL

CLK

LE(CA1)

OUT15

SDI

SDO

GND

R -EXT

VIH, VIL

Iref

April 2003, V0.8-4

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MBI5028

16-bit Constant Current LED Sink Driver with Gain Control

Switching Characteristics

Characteristic

Symbol

Condition

Min.

Typ.

Max.

Unit

100

t_pLH1

t_pLH2

t_pLH3

t_pLH

CLK - OUTn

LE(CA1) -OUTn

Propagation Delay Time

(“L” to “H”)

OE (CA2)-OUTn

CLK - SDO

V_DD=5.0 V

V_DS=0.8 V

V_IH=V_DD

V_IL=GND

R_ext=300 Ω

V_L=4.0 V

R_L=52 Ω

C_L=10 pF

150

t_pHL1

t_pHL2

t_pHL3

t_pHL

CLK - OUTn

LE(CA1) -OUTn

OE (CA2)-OUTn

CLK - SDO

Propagation Delay Time

(“H” to “L”)

200

CLK

t_w(CLK)

t_w(L)

Pulse Width

LE(CA1)

t_w(OE)

OE (CA2)

Hold Time for LE(CA1)

h(L)

Setup Time for LE(CA1)

Maximum CLK Rise Time

Maximum CLK Fall Time

Output Rise Time of Iout

Output Fall Time of Iout

su(L)

500

200

120

t_r**

t_f**

t_or

t_of

**If the devices are connected in cascade and t_ror t is large, it may be critical to achieve the timing required for

data transfer between two cascaded devices.

Test Circuit for Switching Characteristics

IDD

IOUT

VDD

VIH, VIL

OUT0

OE(CA2)

CLK

Function

Generator

LE(CA1)

OUT15

SDI

SDO

GND

R -EXT

Logic input

waveform

VIH = 5V

VIL = 0V

Iref

tr = tf =10 ns

April 2003, V0.8-4

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MBI5028

16-bit Constant Current LED Sink Driver with Gain Control

Timing Waveform

Normal Mode

t_W(CLK)

50%

CLK

SDI

t_su(D)

t_h(D)

50%

SDO

t_W(L)

t_pLH_,t_pHL

50%

LE(CA1)

t_h(L)

t_su(L)

LOW = OUTPUTS ENABLED

(CA2)

HIGH = OUTPUT OFF

LOW = OUTPUT ON

50%

OUTn

t_pLH1_,t_pHL1

t_pLH2_,t_pHL2

t_W(OE)

50%

(CA2)

t_pLH3

t_pHL3

90%

50%

10%

90%

50%

10%

OUTn

t_or

t_of

April 2003, V0.8-4

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MBI5028

16-bit Constant Current LED Sink Driver with Gain Control

Entering Current Adjust Mode

t_W(CLK)

50%

CLK

t_h(CA2)

t_su(CA2)

50%

(CA2)

t_su(CA1)t_h(CA1)

50%

LE(CA1)

2 CLK

April 2003, V0.8-4

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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

80.00

70.00

60.00

50.00

40.00

30.00

20.00

10.00

0.00

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

1.1 1.2 1.3 1.4 1.5

2.5

V_DS(V)

April 2003, V0.8-4

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MBI5028

16-bit Constant Current LED Sink Driver with Gain Control

Adjusting Output Current

The output current of each channel (I_OUT) is set by an external resistor, R_ext. After a power-on

status, the relationship between I_outand R_extis shown in the following figure.

I_OUT(mA)

100

V_DS= 1.0V

500

1000

1500

2000

2500

3000

3500

4000

Resistance of the external resistor, R_ext, in Ω

Also, the output current in milliamps can be calculated from the equation:

I_OUTis (625/ R_ext) x 14.4 x G, approximately,

where R_ext, 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 I_OUT= (625/ R_ext) x 14.4 x G, thus, I_OUTis (625/ R_ext) x 28.8

The magnitude of current is around 50mA at 360Ω and 25mA at 720Ω.

April 2003, V0.8-4

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MBI5028

16-bit Constant Current LED Sink Driver with Gain Control

Entering Current Adjust Mode

CLK

(CA2)

LE(CA1)

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

14 15

CLK

LE(CA1)

16-Bit Configuration Code

SDI

Bit15

Bit14 Bit13 Bit12 Bit11 Bit10

Bit3 Bit2 Bit1 Bit0

: 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 I_ORegulator by a gain, G. The output current resulted by the gain values will be then defined

as: (625/ R_ext) x 14.4 x G

April 2003, V0.8-4

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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

Bit 0 Bit 1 Bit 2 Bit 3 Bit 4 Bit 5 Bit 6 Bit 7 Bit 8 Bit 9 Bit 10 Bit 11 Bit 12 Bit 13 Bit 14 Bit 15

Meaning

HC CC0 CC1 CC2 CC3 CC4 CC5

Default

Value

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.

April 2003, V0.8-4

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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)

0.5 0.65 0.8 0.95 1.1 1.25 1.4 1.55 1.7 1.85

Gain

Resuming to Normal Mode

CLK

(CA2)

Voltage “Low”

LE(CA1)

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.

April 2003, V0.8-4

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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

SDO, 2

SDO, N-1

MBI5028, 1

MBI5028, N-2

SDI, 0

MBI5028, 0

MBI5028, 2

MBI5028, N-1

CLK

LE(CA1)

(CA2)

N x 16 CLK Pulses (Note 1)

CLK

SDI, 0

CC5 CC4 CC3 CC2 CC1 CCC0 HC

CC5 CC4 CC3 CC2 CC1 CC0 HC

Configuration Codes (Note 1) (Note2)

For MBI5028, N -1

For MBI5028, 0

LE(CA1)

(CA2)

LE(CA1) Pulse (Note 3)

Writing the Configuration Codes,

Code k, k = 0… (N x 16 –1)

Resuming to Normal

Mode

Entering Current

Adjust Mode

Note 2:

Note 3:

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.

Gain G = (1+ HC) x (1 + D/64)/2

The LE(CA1) pulse writes the Configuration Codes

to each MBI5028.

D = CC0 x 2⁵+ CC1 x 2⁴+ CC2 x 2³+ CC3 x 2²+

CC4 x 2¹+ CC5 x 2⁰.

April 2003, V0.8-4

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MBI5028

16-bit Constant Current LED Sink Driver with Gain Control

Package Power Dissipation (P_D)

The maximum allowable package power dissipation is determined as P_D(max) = (Tj – Ta) /

R_th(j-a). When 16 channels are turned on simultaneously, the actual package power dissipation

is P_D(act) = (I_DDx V_DD) + (I_OUTx Duty x V_DSx 16). Therefore, to keep P_D(act) ≤ P_D(max), the

allowable output current as a function of duty cycle is:

I_OUT= { [ (Tj – Ta) / R_th(j-a)] – (I_DDx V_DD) } / V_DS/ Duty / 16,

where Tj = 150°C.

(A) I_out= 90mA, V_DS= 1.0V, 16 output channels active

For CNS type package, the thermal resistance is R_th(j-a)= 82 (°C/W)

Iout vs. Duty Cycle at Rth = 82 (°C/W)

100

Ta = 25°C

Ta = 55°C

Ta = 85°C

Duty Cycle

For CF type package, the thermal resistance is R_th(j-a)= 96 (°C/W)

Iout vs. Duty Cycle at Rth = 96 (°C/W)

100

Ta = 25 ℃

Ta = 55 ℃

Ta = 85 ℃

Duty Cycle

April 2003, V0.8-4

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MBI5028

16-bit Constant Current LED Sink Driver with Gain Control

For CP type package, the thermal resistance is R_th(j-a)= 112 (°C/W)

Iout vs. Duty Cycle at Rth = 112 (°C/W)

100

Ta = 25°C

Ta = 55°C

Ta = 85°C

Duty Cycle

(B) I_out= 60mA, V_DS= 0.8V, 16 output channels active

For CNS type package, the thermal resistance is R_th(j-a)= 82 (°C/W)

Iout vs. Duty Cycle at Rth = 82 (°C/W)

Ta = 25°C

Ta = 55°C

Ta = 85°C

Duty Cycle

April 2003, V0.8-4

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MBI5028

16-bit Constant Current LED Sink Driver with Gain Control

For CF type package, the thermal resistance is R_th(j-a)= 96 (°C/W)

Iout vs. Duty Cycle at Rth = 96 (°C/W)

Ta = 25°C

Ta = 55°C

Ta = 85°C

Duty Cycle

For CP type package, the thermal resistance is R_th(j-a)= 112 (°C/W)

Iout vs. Duty Cycle at Rth = 112 (°C/W)

Ta = 25°C

Ta = 55°C

Ta = 85°C

Duty Cycle

April 2003, V0.8-4

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MBI5028

16-bit Constant Current LED Sink Driver with Gain Control

The maximum power dissipation, P_D(max) = (Tj-Ta) / R_th(j-a), decreases as the ambient

temperature increases.

Max. Power Dissipation at Various Ambient Temperature

1.6

1.4

1.2

0.8

0.6

0.4

0.2

CNS Type: Rth = 82

CF Type: Rth = 96

CP Type: Rth = 112

-40 -30 -20 -10

Ambient Temperature

Load Supply Voltage (V_LED)

MBI5028 are designed to operate with V_DSranging from 0.4V to 1.0V considering the package

power dissipating limits. V_DSmay be higher enough to make P_D(act)> P_D(max)when V_LED= 5V

and V_DS= V_LED– Vf, in which V_LEDis the load supply voltage. In this case, it is recommended to

use the lowest possible supply voltage or to set an external voltage reducer (V_DROP).

A voltage reducer lets V_DS= (V_LED– Vf) – V_DROP

Resisters, or Zener diode can be used in the applications as the following figures.

V_LED

V_DROP

V_DS

MBI5028

April 2003, V0.8-4

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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)

April 2003, V0.8-4

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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)

April 2003, V0.8-4

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MBI5028 [ETC]

相关型号：

MBI5028CF

MBI5028CNS

MBI5028CP

MBI5029

MBI5029CD

MBI5029CF

MBI5029CN

MBI5029CNS

MBI5029CP

MBI5029CPA

MBI5029GD

MBI5029GF