900,000+ datasheet pdf search and download

Datasheet4U offers most rated semiconductors data sheet pdf




Maxim Integrated Semiconductor Electronic Components Datasheet

MAX6978 Datasheet

5.5V Constant-Current LED Driver

No Preview Available !

19-3578; Rev 1; 3/05
8-Port, 5.5V Constant-Current LED Driver with
LED Fault Detection and Watchdog
General Description
The MAX6978 serial-interfaced LED driver provides
eight open-drain, constant-current sinking LED driver
outputs rated at 5.5V. The MAX6978 operates from a 3V
to 5.5V supply. The MAX6978 supply and the LEDs’
supply can power up in any order. The constant-current
outputs are programmed together to up to 55mA using
a single external resistor. The MAX6978 operates with a
25Mb, industry-standard, 4-wire serial interface.
The MAX6978 includes circuitry that automatically
detects open-circuit LEDs. Fault status is loaded into the
serial-interface shift register when LE goes high and is
automatically shifted out on DOUT when the next data
transmission is shifted in.
The MAX6978 includes a fail-safe feature for safety-
related applications, which blanks the display if the ser-
ial interface fails. If the serial interface becomes
inactive for more than 1s, all driver output latches are
automatically cleared. This turns off all LEDs connected
to the outputs. The shift register data is not disturbed.
The outputs remain off until the driver output latches are
updated with data turning them on, so recovery is auto-
matic if the transmission failure is temporary. The
watchdogwww.DataSheet4U.com function requires no software change to the
application driving the MAX6978.
The MAX6978 uses the industry-standard shift-register-
plus-latch-type serial interface. The driver accepts data
shifted into an 8-bit shift register using data input DIN
and clock input CLK. Input data appears at the output
DOUT eight clock cycles later to allow cascading of
multiple MAX6978s. The latch-enable input LE loads
the 8 bits of shift-register data into an 8-bit output latch
to set which LEDs are on and which are off. The output-
enable input OE gates all eight outputs on and off, and
is fast enough to be used as a PWM input for LED
intensity control.
The MAX6978 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.
Variable Message Signs
Marquee Displays
Point-of-Order Signs
Traffic Signs
Gaming Features
Architectural Lighting
Applications
Features
25Mb Industry-Standard 4-Wire Serial Interface at 5V
3V to 5.5V Logic Supply
8 Constant-Current LED Outputs Rated at 5.5V
Up to 55mA Continuous Current per Output
Output Current Programmed by Single Resistor
3% Current Matching Between Outputs
6% Current Matching Between ICs
Watchdog Clears Display if Interface Fails
Reports Open-Circuit LED Faults
-40°C to +125°C Temperature Range
Ordering Information
PART
TEMP RANGE
MAX6978AUE
-40°C to +125°C
MAX6978APE
-40°C to +125°C
MAX6978AEE
-40°C to +125°C
*EP = Exposed pad.
PIN-PACKAGE
16 TSSOP-EP*
16 PDIP
16 SSOP
Typical Application Circuit and Selector Guide appear at
end of data sheet.
Pin Configuration
TOP VIEW
GND 1
DIN 2
CLK 3
LE 4
OUT0 5
OUT1 6
OUT2 7
OUT3 8
MAX6978AUE
MAX6978APE
MAX6978AEE
16 V+
15 SET
14 DOUT
13 OE
12 OUT7
11 OUT6
10 OUT5
9 OUT4
TSSOP/PDIP/SSOP
________________________________________________________________ Maxim Integrated Products 1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.


Maxim Integrated Semiconductor Electronic Components Datasheet

MAX6978 Datasheet

5.5V Constant-Current LED Driver

No Preview Available !

8-Port, 5.5V Constant-Current LED Driver with
LED Fault Detection and Watchdog
ABSOLUTE MAXIMUM RATINGS
Voltage (with respect to GND)
V+ ............................................................................-0.3V to +6V
OUT_ .......................................................................-0.3V to +6V
DIN, CLK, LE, OE, SET ................................-0.3V to (V+ + 0.3V)
DOUT Current ..................................................................±10mA
OUT_ Sink Current .............................................................60mA
Total GND Current ...........................................................480mA
Continuous Power Dissipation
16-Pin SSOP (derate 7.1mW/°C over TA = +70°C) .......571mW
16-Pin PDIP (derate 10.5mW/°C over TA = +70°C) ......842mW
16-Pin TSSOP (derate 21.3mW/°C over
TA = +70°C) ..............................................................1702mW
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, TA = TMIN to TMAX, unless otherwise noted. Typical values are at V+ = 5V, TA = +25°C.)
(Note 1)
PARAMETER
Operating Supply Voltage
Output Voltage
Standby Current
(Interface Idle, All Output Ports
High Impedance, RSET = 360)
Standby Current
(Interface Running, All Output
Ports High Impedance,
RSET = 360)
Supply Current
(Interface Idle, All Output Ports
Active Low, RSET = 360)
Input High Voltage
DIN, CLK, LE, OE
SYMBOL
V+
VOUT
CONDITIONS
I+
All logic inputs at V+ or GND, DOUT
unloaded
I+
fCLK = 5MHz, OE = V+, DIN and LE = V+
or GND, DOUT unloaded
I+
All logic inputs at V+ or GND,
DOUT unloaded
VIH
MIN TYP
3.0
4.5
4.7
10
0.7 V+
MAX
5.5
5.5
UNITS
V
V
5.6 mA
6 mA
25 mA
V
Input Low Voltage
DIN, CLK, LE, OE
VIL
0.3 V+
V
Hysteresis Voltage
DIN, CLK, LE, OE
VI
0.8 V
Input Leakage Current
DIN, CLK, LE, OE
IIH, IIL
-1 +1 µA
Output-High Voltage DOUT
Output Low Voltage
Output Current
OUT_
Output Leakage Current OUT_
Watchdog Timeout
VOH
VOL
IOUT
ILEAK
tWD
ISOURCE = 4mA
ISINK = 4mA
V+ = 3V to 5.5V, VOUT = 0.8V to 2.5V,
RSET = 360
OE = V+, VOUT = V+
V+
- 0.5V
V
0.5 V
42 50 56 mA
1 µA
1s
2 _______________________________________________________________________________________


Part Number MAX6978
Description 5.5V Constant-Current LED Driver
Maker Maxim Integrated Products
Total Page 13 Pages
PDF Download

MAX6978 Datasheet PDF

View PDF for Mobile








Similar Datasheet

1 MAX697 Microprocessor Supervisory Circuits
Maxim
2 MAX6970 36V Constant-Current LED Driver
Maxim Integrated
3 MAX6971 36V Constant-Current LED Driver
Maxim Integrated Products
4 MAX6972 (MAX6972 / MAX6973) 16-Output PWM LED Drivers
Maxim Integrated Products
5 MAX6973 (MAX6972 / MAX6973) 16-Output PWM LED Drivers
Maxim Integrated Products
6 MAX6974 (MAX6974 / MAX6975) 24-Output PWM LED Drivers
Maxim Integrated Products
7 MAX6975 (MAX6974 / MAX6975) 24-Output PWM LED Drivers
Maxim Integrated Products
8 MAX6977 5.5V Constant-Current LED Driver
Maxim Integrated
9 MAX6978 5.5V Constant-Current LED Driver
Maxim Integrated Products





Part Number Start With

0    1    2    3    4    5    6    7    8    9    A    B    C    D    E    F    G    H    I    J    K    L    M    N    O    P    Q    R    S    T    U    V    W    X    Y    Z

Site map

Webmaste! click here

Contact us

Buy Components

Privacy Policy