MAX6971_07,MAX6971_07 pdf中文资料,MAX6971_07引脚图,MAX6971

19-3808; Rev 1; 10/07

IT

TION K

VALUA

E

BLE

AVAILA

16-Port, 36V Constant-Current LED Driver

General Description

The MAX6971 serial-interfaced LED driver provides 16

open-drain, constant-current-sinking LED driver outputs

rated at 36V. The MAX6971 operates from a 3V to 5.5V

supply. The MAX6971 supply and the LEDs’ supply or

supplies can power up in any order. The constant-cur-

rent outputs are programmed together to up to 55mA

using a single external resistor. The MAX6971 operates

with a 25Mb, industry-standard, 4-wire serial interface.

The MAX6971 uses the industry-standard, shift-register-

plus-latch-type serial interface. The driver accepts data

shifted into a 16-bit shift register using data input DIN

and clock input CLK. Input data appears at the DOUT

output 16 clock cycles later to allow cascading of multi-

ple MAX6971s. The latch-enable input, LE, loads the 16

bits of shift register data into a 16-bit output latch to set

which LEDs are on and which are off. The output-

enable,

OE,

gates all 16 outputs on and off, and is fast

enough to be used as a PWM input for LED intensity

control.

For applications requiring LED fault detection, refer to

the MAX6983, which automatically detects open-circuit

LEDs.

For safety-related applications requiring a watchdog

timer, refer to the MAX6983, which includes a fail-safe

feature that blanks the display if the serial interface

becomes inactive for more than 1s.

The MAX6971 is one of a family of 12 shift-register-plus-

latch-type LED drivers. The family includes 8-port and

16-port types, with 5.5V- or 36V-rated LED outputs, with

and without open-circuit LED detection and watchdog.

All versions operate from a 3V to 5.5V supply, and are

specified over the -40°C to +125°C temperature range.

♦

3V to 5.5V Logic Supply

♦

16 Constant-Current LED Outputs Rated at 36V

♦

Up to 55mA Continuous Current per Output

♦

Output Current Programmed by Single Resistor

♦

3% Current Matching Between Outputs

♦

6% Current Matching Between ICs

♦

High-Dissipation, 24-Pin Packages

♦

-40°C to +125°C Temperature Range

Features

♦

25Mb, Industry-Standard, 4-Wire Serial Interface

MAX6971

Ordering Information

PART

MAX6971AUG

MAX6971ANG

TEMP RANGE

-40°C to +125°C

PIN-PACKAGE

24 TSSOP

24 Narrow PDIP

Typical Application Circuit and Selector Guide appear at

end of data sheet.

Pin Configuration

TOP VIEW

GND 1

DIN 2

24 V+

23 SET

22 DOUT

21 OE

Applications

Variable Message Signs

Marquee Displays

Point-of-Order Signs

Traffic Signs

Gaming Features

Architectural Lighting

CLK 3

LE 4

OUT0 5

OUT1 6

OUT2 7

OUT3 8

OUT4 9

OUT5 10

OUT6 11

OUT7 12

MAX6971AUG

MAX6971ANG

20 OUT15

19 OUT14

18 OUT13

17 OUT12

16 OUT11

15 OUT10

14 OUT9

13 OUT8

TSSOP/PDIP

________________________________________________________________

Maxim Integrated Products

1

For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,

or visit Maxim’s website at www.maxim-ic.com.

16-Port, 36V Constant-Current LED Driver

MAX6971

ABSOLUTE MAXIMUM RATINGS

Voltage with respect to GND.

V+ ............................................................................-0.3V to +6V

OUT_ .....................................................................-0.3V to +40V

DIN, CLK, LE,

OE,

SET ................................-0.3V to (V+ + 0.3V)

DOUT Current ..................................................................±10mA

OUT_ Sink Current .............................................................60mA

Total GND Current ...........................................................960mA

Continuous Power Dissipation (T

A

= +70°C)

24-Pin TSSOP (derate 12.2mW/°C over +70°C) ..........975mW

24-Pin PDIP (derate 13.3mW/°C over +70°C)............1067mW

Operating Temperature Range .........................-40°C to +125°C

Junction Temperature ......................................................+150°C

Storage Temperature Range .............................-65°C to +150°C

Lead Temperature (soldering, 10s) .................................+300°C

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional

operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to

absolute maximum rating conditions for extended periods may affect device reliability.

ELECTRICAL CHARACTERISTICS

(Typical

Operating Circuit,

V+ = 3V to 5.5V, T

A

= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at V+ = 5V, T

A

= +25°C.)

(Note 1)

PARAMETER

Operating Supply Voltage

Output Voltage

Standby Current

(Interface Idle, All Output Ports

High Impedance, R

SET

= 360Ω)

Standby Current

(Interface Running, All Output

Ports High Impedance,

R

SET

= 360Ω)

Supply Current

(Interface Idle, All Output Ports

Active Low, R

SET

= 360Ω)

Input High Voltage

DIN, CLK, LE,

OE

Input Low Voltage

DIN, CLK, LE,

OE

Hysteresis Voltage

DIN, CLK, LE,

OE

Input Leakage Current

DIN, CLK, LE,

OE

Output High-Voltage DOUT

Output Low Voltage

Output Current OUT_

Output Leakage Current OUT_

SYMBOL

V+

V

OUT

I

+

All logic inputs at V+ or GND, DOUT

unloaded

5.7

CONDITIONS

MIN

3.0

TYP

MAX

5.5

36

8

UNITS

V

mA

I

+

f

CLK

= 5MHz,

OE

= V+, DIN and LE = V+

or GND, DOUT unloaded

6

8.5

mA

I

+

All logic inputs at V+ or GND,

DOUT unloaded

0.7 x

V+

18

25

mA

V

IH

V

IL

ΔV

I

IH

, I

IL

V

OH

V

OL

I

OUT

I

LEAK

I

SOURCE

= 4mA

I

SINK

= 4mA

V+ = 3V to 5.5V, V

OUT

= 0.8V to 2.5V,

R

SET

= 360Ω

OE

= V+

V

0.3 x

V+

0.8

V

+1

µA

V

0.5

V

mA

µA

-1

V+

- 0.5V

37

50

61

1

Note 1:

All parameters tested at T

A

= +25°C. Specifications over temperature are guaranteed by design.

2

_______________________________________________________________________________________

16-Port, 36V Constant-Current LED Driver

5V TIMING CHARACTERISTICS

(Typical

Operating Circuit,

V+ = 4.5V to 5.5V, T

A

= T

MIN

to T

MAX

, unless otherwise noted.) (Notes 1, 2, 3)

PARAMETER

CLK Clock Period

CLK Pulse-Width High

CLK Pulse-Width Low

DIN Setup Time

DIN Hold Time

DOUT Propagation Delay

DOUT Rise and Fall Time

LE Pulse-Width High

LE Setup Time

LE Rising to OUT_ Rising Delay

LE Rising to OUT_ Falling Delay

CLK Rising to OUT_ Rising Delay

CLK Rising to OUT_ Falling Delay

OE

Rising to OUT_ Rising Delay

OE

Falling to OUT_ Falling Delay

LED Output OUT_ Turn-On Fall

Time

LED Output OUT_ Turn-Off Rise

Time

SYMBOL

t

CP

t

CH

t

CL

t

DS

t

DH

t

DO

t

DR,

t

DF

t

LW

t

LS

t

LRR

t

LRF

t

CRR

t

CRF

t

OEH

t

OEL

t

f

t

r

(Note 3)

80% to 20%, pullup resistor = 65Ω

20% to 80%, pullup resistor = 65Ω

C

DOUT

= 10pF, 20% to 80%

20

10

100

300

100

310

100

320

120

CONDITIONS

MIN

40

19

4

8

12

32

10

TYP

MAX

UNITS

ns

MAX6971

Note 1:

All parameters tested at T

A

= +25°C. Specifications over temperature are guaranteed by design.

Note 2:

See Figure 3.

Note 3:

A 65Ω pullup resistor connected from OUT_ to 5.5V.

_______________________________________________________________________________________

3

16-Port, 36V Constant-Current LED Driver

MAX6971

3.3V TIMING CHARACTERISTICS

(Typical

Operating Circuit,

V+ = 3V to 5.5V, T

A

= T

MIN

to T

MAX

, unless otherwise noted.) (Notes 1, 2)

PARAMETER

CLK Clock Period

CLK Pulse-Width High

CLK Pulse-Width Low

DIN Setup Time

DIN Hold Time

DOUT Propagation Delay

DOUT Rise and Fall Time

LE Pulse-Width High

LE Setup Time

LE Rising to OUT_ Rising Delay

LE Rising to OUT_ Falling Delay

CLK Rising to OUT_ Rising Delay

CLK Rising to OUT_ Falling Delay

OE

Rising to OUT_ Rising Delay

OE

Falling to OUT_ Falling Delay

LED Output OUT_ Turn-On Fall

Time

LED Output OUT_ Turn-Off Rise

Time

SYMBOL

t

CP

t

CH

t

CL

t

DS

t

DH

t

DO

t

DR,

t

DF

t

LW

t

LS

t

LRR

t

LRF

t

CRR

t

CRF

t

OEH

t

OEL

t

f

t

r

(Note 3)

80% to 20% (Note 3)

20% to 80% (Note 3)

C

DOUT

= 10pF, 20% to 80%

20

15

120

310

120

330

120

330

120

CONDITIONS

MIN

52

24

4

8

12

50

12

TYP

MAX

UNITS

ns

Note 1:

All parameters tested at T

A

= +25°C. Specifications over temperature are guaranteed by design.

Note 2:

See Figure 3.

Note 3:

A 65Ω pullup resistor connected from OUT_ to 5.5V.

Typical Operating Characteristics

(T

A

= +25°C, unless otherwise noted.)

SUPPLY CURRENT vs. SUPPLY VOLTAGE

(INTERFACE IDLE, ALL OUTPUTS OFF,

R

SET

= 720Ω)

MAX6971 toc01

MAX6971 toc02

T

A

= +85°C

T

A

= +125°C

T

A

= +125°C

SUPPLY CURRENT (mA)

1.95

T

A

= +85°C

35

SUPPLY CURRENT (mA)

30

25

20

SUPPLY CURRENT (mA)

3.65

T

A

= +125°C

3.60

T

A

= +85°C

1.90

T

A

= -40°C

1.85

T

A

= +25°C

T

A

= +25°C

T

A

= -40°C

3.55

T

A

= -40°C

T

A

= +25°C

15

10

1.80

3.0

3.5

4.0

4.5

5.0

5.5

SUPPLY VOLTAGE (V)

3.50

3.0

3.5

4.0

4.5

5.0

5.5

SUPPLY VOLTAGE (V)

3.0

3.5

4.0

4.5

5.0

5.5

SUPPLY VOLTAGE (V)

4

_______________________________________________________________________________________

MAX6971 toc03

2.00

3.70

SUPPLY CURRENT vs. SUPPLY VOLTAGE

(INTERFACE IDLE, ALL OUTPUTS OFF,

R

SET

= 360Ω)

SUPPLY CURRENT vs. SUPPLY VOLTAGE

(INTERFACE IDLE, ALL OUTPUTS ON, R

SET

= 720Ω)

40

16-Port, 36V Constant-Current LED Driver

MAX6971

Typical Operating Characteristics (continued)

(T

A

= +25°C, unless otherwise noted.)

SUPPLY CURRENT vs. SUPPLY VOLTAGE

(INTERFACE IDLE, ALL OUTPUTS ON, R

SET

= 360Ω)

MAX6971 toc04

PORT OUTPUT CURRENT vs. PORT OUTPUT

VOLTAGE (R

SET

= 720Ω, V+ = 3.3V)

MAX6971 toc05

PORT OUTPUT CURRENT vs. PORT OUTPUT

VOLTAGE (R

SET

= 360Ω, V+ = 3.3V)

T

A

= -40°C

MAX6971 toc06

45

40

SUPPLY CURRENT (mA)

T

A

= +125°C

35

30

25

20

15

3.0

3.5

4.0

4.5

5.0

T

A

= +25°C

T

A

= +85°C

30

25

20

15

10

5

0

T

A

= -40°C

60

50

40

30

T

A

= +125°C

20

10

0

PORT OUTPUT CURRENT (mA)

T

A

= +25°C

T

A

= +85°C

T

A

= +125°C

T

A

= +25°C

T

A

= +85°C

T

A

= -40°C

5.5

0

0.5

1.0

1.5

2.0

2.5

3.0

0

0.5

1.0

1.5

2.0

2.5

3.0

SUPPLY VOLTAGE (V)

PORT OUTPUT VOLTAGE (V)

PORT OUTPUT CURRENT vs. PORT OUTPUT

VOLTAGE (R

SET

= 720Ω, V+ = 5.0V)

MAX6971 toc07

PORT OUTPUT CURRENT vs. PORT OUTPUT

VOLTAGE (R

SET

= 360Ω, V+ = 5.0V)

MAX6971 toc08

PORT OUTPUT CURRENT vs. SUPPLY

VOLTAGE (R

SET

= 720Ω, V

OUT

= 2V)

MAX6971 toc09

30

T

A

= -40°C

PORT OUTPUT CURRENT (mA)

25

20

15

10

5

0

0.5

1.0

1.5

2.0

2.5

T

A

= +25°C

T

A

= +85°C

T

A

= +125°C

60

T

A

= -40°C

PORT OUTPUT CURRENT (mA)

50

40

T

A

= +25°C

30

20

10

0

T

A

= +85°C

T

A

= +125°C

25.0

PORT OUTPUT CURRENT (mA)

24.5

T

A

= +125°C

24.0

T

A

= +85°C

T

A

= +25°C

23.5

T

A

= -40°C

23.0

0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

5.5

PORT OUTPUT VOLTAGE (V)

SUPPLY VOLTAGE (V)

3.0

PORT OUTPUT VOLTAGE (V)

PORT OUTPUT CURRENT vs. SUPPLY

VOLTAGE (R

SET

= 360Ω, V

OUT

= 2V)

MAX6971 toc10

PORT OUTPUT CURRENT

vs. R

SET

RESISTANCE (V+ = 5.0V)

MAX6971 toc11

49

50

PORT OUTPUT CURRENT (mA)

40

48

T

A

= -40°C

T

A

= +25°C

30

20

47

T

A

= +125°C

T

A

= +85°C

10

46

3.0

3.5

4.0

4.5

5.0

5.5

SUPPLY VOLTAGE (V)

0

1

2

3

4

5

R

SET

RESISTANCE (kΩ)

_______________________________________________________________________________________

5

MAX6971_07

MAX6971_07概述

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