CAT4104 D

CAT4104
700 mA Quad Channel
Constant Current LED Driver
Description
The CAT4104 provides four matched low dropout current sinks to
drive high−brightness LED strings up to 175 mA per channel. The
LED channel current is set by an external resistor connected to the
RSET pin. The LED pins are compatible with high voltage up to 25 V
supporting applications with long strings of LEDs.
The EN/PWM logic input supports the device enable and high
frequency external Pulse Width Modulation (PWM) dimming control.
Thermal shutdown protection is incorporated in the device to
disable the LED outputs whenever the die temperature exceeds 150°C.
The device is available in the 8−pad TDFN 2 mm x 3 mm package
and the SOIC 8−Lead 150 mil wide package.
Features
•
•
•
•
•
•
•
•
•
4 Matched LED Current Sinks up to 175 mA
Up to 25 V Operation on LED Pins
Low Dropout Current Source (0.4 V at 175 mA)
LED Current Set by External Resistor
High Frequency PWM Dimming via EN/PWM
“Zero” Current Shutdown Mode
Thermal Shutdown Protection
TDFN 8−pad 2 x 3 mm and SOIC 8−lead Packages
These Devices are Pb−Free, Halogen Free/BFR Free and are RoHS
Compliant
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PIN CONNECTIONS
LED1
1
RSET
LED2
VIN
LED3
EN/PWM
LED4
GND
SOIC 8−lead
(Top View)
1
LED3
RSET
VIN
EN/PWM
LED4
GND
LED1
LED2
TDFN 8−pad
(Top View)
Applications
• Automotive Lighting
• General and Architectural Lighting
• LCD Backlight
TDFN−8
VP SUFFIX
CASE 511AK
SOIC−8
V SUFFIX
CASE 751BD
MARKING DIAGRAMS
VCC
3 V to 25 V
CAT4104V
HC
LEDs
VIN
5V
OFF ON
R1
768 W
CAT4104V = CAT4104V
HC = CAT4104VP2
CAT4104
LED1
VIN
EN/PWM
RSET
GND
LED2
ORDERING INFORMATION
LED3
LED4
Device
175 mA
Figure 1. Typical Application Circuit
Package
Shipping
CAT4104V−GT3
(Note 1)
SOIC−8
(Pb−Free)
3,000/
Tape & Reel
CAT4104VP2−GT3
(Note 1)
TDFN−8
(Pb−Free)
3,000/
Tape & Reel
1. Lead Finish is NiPdAu
© Semiconductor Components Industries, LLC, 2010
March, 2010 − Rev. 2
1
Publication Order Number:
CAT4104/D
CAT4104
Table 1. ABSOLUTE MAXIMUM RATINGS
Parameter
Rating
Unit
VIN, RSET, EN/PWM Voltages
−0.3 to 6
V
LED1, LED2, LED3, LED4 Voltages
−0.3 to 25
V
Storage Temperature Range
−65 to +160
_C
Junction Temperature Range
−40 to +150
_C
300
_C
Lead Temperature
Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the
Recommended Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect
device reliability.
Table 2. RECOMMENDED OPERATING CONDITIONS
Parameter
Rating
Unit
VIN
3.0 to 5.5
V
Voltage applied to LED1 to LED4, outputs off
up to 25
V
Voltage applied to LED1 to LED4, outputs on
up to 6 (Note 2)
V
Ambient Temperature Range
−40 to +85
_C
ILED per LED pin
10 to 175
mA
2. Keeping LEDx pin voltage below 6 V in operation is recommended to minimize thermal dissipation in the package.
NOTE: Typical application circuit with external components is shown on page 1.
Table 3. ELECTRICAL OPERATING CHARACTERISTICS (Min and Max values are over the recommended operating conditions
unless specified otherwise. Typical values are at VIN = 5.0 V, TAMB = 25°C.)
Name
Symbol
ILED−ACC
Conditions
LED Current Accuracy
Min
Typ
Max
%
±2
I LEDNOM * I LED
Units
I LEDNOM
ILED−DEV
LED Channel Matching
I LED * I LEDAVG
I LEDAVG
(Note 3)
VDOUT
Dropout Voltage
VRSET
RSET Pin Voltage
IQ
Quiescent Current
No LED, RSET = Float
No LED, RSET = 770 W
IQSHDN
Shutdown Current
VEN = 0 V
REN/PWM
VHI
VLO
−5
ILED = 175 mA
+5
400
1.17
EN/PWM Pin
− Internal pull−down resistance
− Logic High Level
− Logic Low Level
±1
1.2
%
mV
1.23
0.6
6
V
mA
1
mA
0.4
kW
V
V
200
1.3
TSD
Thermal Shutdown
150
°C
THYS
Thermal Hysteresis
20
°C
ILED/IRSET
VUVLO
RSET to LED Current gain ratio
25 mA LED current
Undervoltage lockout (UVLO) threshold
100
2.0
3. Min and Max values are tested for ILED = 50 mA, VIN = 3.5 V, VLEDx = 0.4 V, TAMB = 25°C.
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2
V
CAT4104
Table 4. RECOMMENDED EN/PWM TIMING (Min and Max values are over the recommended operating conditions unless
specified otherwise. Typical values are at VIN = 5.0 V, TAMB = 25°C.)
Name
Symbol
Conditions
Min
Typ
Max
Units
TPS
Turn−On time, EN/PWM rising to ILED from
shutdown
ILED = 175 mA
ILED = 80 mA
1.5
1.3
ms
TP1
Turn−On time, EN/PWM rising to ILED
ILED = 175 mA
600
ns
TP2
Turn−Off time, EN/PWM falling to ILED
ILED = 175 mA
ILED = 80 mA
400
300
ns
TR
LED rise time
ILED = 175 mA
ILED = 80 mA
700
440
ns
TF
LED fall time
ILED = 175 mA
ILED = 80 mA
360
320
ns
TLO
EN/PWM low time
1
ms
THI
EN/PWM high time
5
ms
TPWRDWN
EN/PWM low time to shutdown delay
4
THI
8
ms
TPWRDWN
TLO
EN/PWM
SHUTDOWN
POWERDOWN
TP2
LED CURRENT
SHUTDOWN 0 mA
TF
TP1 TR
TPS
50%
50%
I LED +
1.2 V
R SET
SHUTDOWN 0 mA
100
90%
10%
0 mA
QUIESCENT CURRENT
SHUTDOWN 0 mA
SHUTDOWN 0 mA
Figure 2. CAT4104 EN/PWM Timing
EN/PWM Operation
The EN/PWM pin has two primary functions. One
function enables and disables the device. The other function
turns the LED channels on and off for PWM dimming
control. The device has a very fast turn−on time (from
EN/PWM rising to LED on) and allows “instant on” when
dimming LED using a PWM signal.
Accurate linear dimming is compatible with PWM
frequencies from 100 Hz to 5 kHz for PWM duty cycle
down to 1%. PWM frequencies up to 50 kHz can be
supported for duty cycles greater than 10%.
When performing a combination of low frequencies and
small duty cycles, the device may enter shutdown mode.
This has no effect on the dimming accuracy, because the
turn−on time TPS is very short, in the range of 1 ms.
To ensure that PWM pulses are recognized, pulse width
low time TLO should be longer than 1 ms. The CAT4104
enters a “zero current” shutdown mode after a 4 ms delay
(typical) when EN/PWM is held low.
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CAT4104
TYPICAL PERFORMANCE CHARACTERISTICS
(VIN = 5 V, VCC = 5 V, LED forward voltage = 3.5 V, CIN = 1 mF, TAMB = 25°C unless otherwise specified.)
8
No Load
QUIESCENT CURRENT (mA)
QUIESCENT CURRENT (mA)
1.2
1.0
0.8
0.6
0.4
3.0
3.5
4.0
4.5
5.0
2
0.5
1.0
1.5
2.0
RSET CURRENT (mA)
Figure 3. Quiescent Current vs. Input Voltage
(RSET Open)
Figure 4. Quiescent Current vs. RSET Current
200
Full Load
160
LED CURRENT (mA)
6.5
6.0
5.5
120
80
40
3.0
3.5
4.0
4.5
5.0
0
5.5
0
0.2
0.4
0.6
0.8
INPUT VOLTAGE (V)
LED PIN VOLTAGE (V)
Figure 5. Quiescent Current vs. Input Voltage
(Full Load)
Figure 6. LED Dropout vs. LED Pin Voltage
200
200
160
160
120
80
40
0
0
INPUT VOLTAGE (V)
LED CURRENT (mA)
QUIESCENT CURRENT (mA)
LED CURRENT (mA)
4
0
5.5
7.0
5.0
6
1.0
120
80
40
3.0
3.5
4.0
4.5
5.0
0
−40
5.5
0
40
80
VIN (V)
TEMPERATURE (°C)
Figure 7. LED Line Regulation
Figure 8. LED Current Change vs.
Temperature
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120
CAT4104
TYPICAL PERFORMANCE CHARACTERISTICS
(VIN = 5 V, VCC = 5 V, LED forward voltage = 3.5 V, CIN = 1 mF, TAMB = 25°C unless otherwise specified.)
1000
200
LED CURRENT (mA)
LED CURRENT (mA)
160
100
120
80
40
0.1
1
0
10
2
3
4
5
Figure 9. LED Current vs. RSET Resistor
Figure 10. LED Current vs. LED Pin Voltage
1.25
1.25
RSET VOLTAGE (V)
1.30
1.20
1.15
3.0
1
LED PIN VOLTAGE (V)
1.30
1.10
0
RSET (kW)
3.5
4.0
4.5
5.0
1.20
1.15
1.10
−40
5.5
6
0
40
80
120
INPUT VOLTAGE (V)
TEMPERATURE (°C)
Figure 11. RSET Pin Voltage vs. Input Voltage
Figure 12. RSET Pin Voltage vs. Temperature
1.0
LED OFF CURRENT (mA)
RSET VOLTAGE (V)
10
0.8
0.6
−40°C
0.4
25°C
0.2
125°C
0
0
5
10
15
20
25
LED PIN VOLTAGE (V)
Figure 13. LED Off Current vs. LED Pin
Voltage
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5
30
CAT4104
TYPICAL PERFORMANCE CHARACTERISTICS
(VIN = 5 V, VCC = 5 V, LED forward voltage = 3.5 V, CIN = 1 mF, TAMB = 25°C unless otherwise specified.)
1.4
ENABLE THRESHOLD (V)
ENABLE CURRENT (mA)
25
20
15
10
5
0
0
1
2
3
4
1.2
25°C
0.8
85°C
0.6
0.4
5
−40°C
1.0
3.0
3.5
4.0
4.5
5.0
ENABLE VOLTAGE (V)
INPUT VOLTAGE (V)
Figure 14. EN/PWM Pull−down Current vs.
VEN/PWM
Figure 15. EN/PWM Threshold vs. VIN
Figure 16. Power Up from Shutdown
Figure 17. Power Down
Figure 18. PWM 200 Hz, 1% Duty Cycle
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5.5
CAT4104
Table 5. PIN DESCRIPTIONS
Name
Pin
SOIC 8−Lead
Pin
TDFN 8−Lead
LED1
1
1
LED1 cathode terminal
LED2
2
2
LED2 cathode terminal
LED3
3
3
LED3 cathode terminal
LED4
4
4
LED4 cathode terminal
GND
5
5 and TAB
EN/PWM
6
6
Device enable input and PWM control
VIN
7
7
Device supply pin
RSET
8
8
LED current set pin for the LED channels
Function
Ground reference
Pin Function
VIN is the supply pin for the device. A small 0.1 mF ceramic
bypass capacitor is optional for noisy environments.
Whenever the input supply falls below the under−voltage
threshold, all LED channels are automatically disabled.
EN/PWM is the enable and one wire dimming input for all
LED channels. Guaranteed levels of logic high and logic low
are set at 1.3 V and 0.4 V respectively. When EN/PWM is
initially taken high, the device becomes enabled and all LED
currents are set at a gain of 100 times the current in RSET.
To place the device into zero current shutdown mode, the
EN/PWM pin must be held low for 4 ms typical.
LED1 to LED4 provide individual regulated currents for
each of the LED cathodes. There pins enter a high
impedance zero current state whenver the device is placed
in shutdown mode.
RSET pin is connected to an external resistor to set the LED
channel current. The ground side of the external resistor
should be star connected to the GND of the PCB. The pin
source current mirrors the current to the LED sinks. The
voltage at this pin is regulated to 1.2 V.
GND is the ground reference for the device. The pin must be
connected to the ground plane on the PCB.
TAB (TDFN 8−Lead Only) is the exposed pad underneath
the package. For best thermal performance, the tab should be
soldered to the PCB and connected to the ground plane.
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CAT4104
Block Diagram
VIN
LED1 LED2
LED3
LED4
VIN
EN/PWM
1.2 V Reference
RSET
4 Current Sink
Regulators
Current Setting
GND
Figure 19. CAT4104 Functional Block Diagram
Basic Operation
The CAT4104 has four tightly matched current sinks to
regulate LED current in each channel. The LED current in
the four channels is mirrored from the current flowing
through the RSET pin according to the following formula:
I LED ^ 100
Tight current regulation for all channels is possible over
a wide range of input voltages and LED voltages due to
independent current sensing circuitry on each channel.
Each LED channel needs a minimum of 400 mV
headroom to sink constant regulated current up to 175 mA.
If the input supply falls below 2 V, the under−voltage
lockout circuit disables all LED channels. Any unused LED
channels should be left open.
For applications requiring more than 175 mA current,
LED channels can be tied together to sink up to a total of
700 mA from the one device.
The LED channels can withstand voltages up to 25 V. This
makes the device ideal for driving long strings of high power
LEDs from a high voltage source.
1.2 V
R SET
Table 6 shows standard resistor values for RSET and the
corresponding LED current.
Table 6. RSET RESISTOR SETTINGS
LED Current [mA]
RSET [kW]
20
6.34
60
2.10
100
1.27
175
0.768
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CAT4104
Application Information
Single 12 V Supply
Nightlight Detection
The circuit shown in Figure 20 shows how to power the
LEDs from a single 12 V supply using the CAT4104. Three
external components are needed to create a lower voltage
necessary for the VIN pin (below 5.5 V). The resistor R2 and
zener diode Z provide a regulated voltage while the
quiescent current runs through the N−Channel transistor M.
The recommended parts are ON Semiconductor MM3Z6V2
zener diode (in SOD−323 package), and 2N7002L
N−Channel transistor (in SOT23).
The circuit shown in Figure 22 illustrates how to use the
CAT4104 in an automatic night light application. The light
sensor allows the CAT4104 to be disabled during the day and
enabled during the night. Five external components are
needed to properly configure the part for night detection.
Resistor R3 limits the quiescent current through the
N−Channel transistor M. Resistors R1 and R2 act as a
voltage divider to create the required voltage to turn on
transistor M, which disables the CAT4104. The
recommended parts are ON Semiconductor 2N7002L
N−Channel transistor (in SOT23) and the Microsemi
LX1972 light sensor. For best performance, the LED light
should not interfere with the light sensor.
12 V
C2
1 mF
R2
5 kW
M
Z
6.2 V
5V
VIN
LED1
CAT4104
LED2
EN/PWM
LED3
C1
0.1 mF
C2
1 mF
VDD
Light
Sensor
RSET LED4
GND
R1
R1
100 kW
VSS
Figure 20. Single Supply Driving 12 LEDs
R2
1 MW
Daylight Detection
The circuit in Figure 21 shows how to use CAT4104 in an
automatic light sensor application. The light sensor allows
the CAT4104 to be enabled during the day and disabled
during the night. Two external components are required to
configure the part for ambient light detection and conserve
power. Resistor R1 sets the bias for the light sensor. The
recommended part is Microsemi LX1972 light sensor. For
best performance, the LED light should not interfere with
the light sensor.
VSS
C1
0.1 mF
OFF ON
R1
OFF ON
M
R4
VIN
LED1
CAT4104
LED2
LED3
EN/PWM
RSET LED4
GND
LED Current Derating
The circuit shown in Figure 23 provides LED temperature
derating to avoid over−driving the LED under high ambient
temperatures, by reducing the LED current to protect the
LED from over−heating. The positive thermo coefficient
(PTC) thermistor RPTC is used for temperature sensing and
should be located near the LED. As the temperature of
RPTC increases, the gate voltage of the MOSFET M1
decreases. This causes the transistor M1 on−resistance to
increase which results in a reduction of the LED current. The
circuit is powered from a single VCC voltage of 5 V. The
recommended parts are Vishay 70°C thermistor
PTCSS12T071DTE and ON Semiconductor 2N7002L
N−Channel transistor (in SOT23).
The PCB and heatsink for the LED should be designed
such that the LED current is constant within the normal
temperature range. But as soon as the ambient temperature
exceeds a max threshold, the LED current drops to protect
the LEDs from overheating.
R1
100 kW
VDD
Light
Sensor
C1
0.1 mF
Figure 22. Nightlight Detection
5V
C2
1 mF
R3
100 kW
VIN
LED1
CAT4104
LED2
LED3
EN/PWM
RSET LED4
GND
Figure 21. Daylight Detection
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9
CAT4104
VCC
5V
C2
1 mF
For a given package style and board layout, the operating
junction temperature TJ is a function of the power
dissipation PD, and the ambient temperature, resulting in the
following equation:
RPTC
VIN
LED1
CAT4104
LED2
C1
0.1 mF
T J + T AMB ) P D(q JC ) q CA) + T AMB ) P D q JA
350 mA
When mounted on a double−sided printed circuit board
with two square inches of copper allocated for “heat
spreading”, the resulting qJA is about 90°C/W for the
TDFN−8 package, and 160°C/W for the SOIC−8 package.
For example, at 60°C ambient temperature, the maximum
power dissipation for the TDFN−8 is calculated as follow:
EN/PWM LED3
R1
1436 W
LED4
RSET
GND
P Dmax +
M1
R2
5 kW
T Jmax * T AMB
+ 150 * 60 + 1 W
q JA
90
Recommended Layout
A small ceramic capacitor should be placed as close as
possible to the driver VIN pin. The RSET resistor should
have a Kelvin connection to the GND pin of the CAT4104.
The board layout should provide good thermal dissipation
through the PCB. In the case of the CAT4104VP2 in the
TDFN package, a via can be used to connect the center tab
to a large ground plane underneath as shown on Figure 24.
Figure 23. LED Current Derating
Power Dissipation
The power dissipation (PD) of the CAT4104 can be
calculated as follows:
P D + (V IN
I IN) ) S(V LEDN
I LEDN)
where VLEDN is the voltage at the LED pin, and ILEDN is the
LED current. Combinations of high VLEDN voltage and high
ambient temperature can cause the CAT4104 to enter
thermal shutdown. In applications where VLEDN is high, a
resistor can be inserted in series with the LED string to lower
the power dissipation PD.
Thermal dissipation of the junction heat consists
primarily of two paths in series. The first path is the junction
to the case (qJC) thermal resistance which is defined by the
package style, and the second path is the case to ambient
(qCA) thermal resistance, which is dependent on board
layout. The overall junction to ambient (qJA) thermal
resistance is equal to:
Figure 24. CAT4104 Recommended Layout
q JA + q JC ) q CA
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CAT4104
PACKAGE DIMENSIONS
SOIC 8, 150 mils
CASE 751BD−01
ISSUE O
SYMBOL
E1
E
MIN
MAX
A
1.35
1.75
A1
0.10
0.25
b
0.33
0.51
c
0.19
0.25
D
4.80
5.00
E
5.80
6.20
E1
3.80
4.00
1.27 BSC
e
PIN # 1
IDENTIFICATION
NOM
h
0.25
0.50
L
0.40
1.27
θ
0º
8º
TOP VIEW
D
h
A1
θ
A
c
e
b
L
END VIEW
SIDE VIEW
Notes:
(1) All dimensions are in millimeters. Angles in degrees.
(2) Complies with JEDEC MS-012.
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CAT4104
PACKAGE DIMENSIONS
TDFN8, 2x3
CASE 511AK−01
ISSUE A
D
A
e
b
E2
E
PIN#1
IDENTIFICATION
A1
PIN#1 INDEX AREA
D2
TOP VIEW
SYMBOL
MIN
SIDE VIEW
NOM
A
0.70
0.75
0.80
0.00
0.02
0.05
A2
0.45
0.55
0.65
A2
0.20 REF
A3
b
0.20
0.25
0.30
D
1.90
2.00
2.10
D2
1.30
1.40
1.50
E
2.90
3.00
3.10
E2
1.20
1.30
1.40
e
L
BOTTOM VIEW
MAX
A1
A3
FRONT VIEW
0.50 TYP
0.20
0.30
L
0.40
Notes:
(1) All dimensions are in millimeters.
(2) Complies with JEDEC MO-229.
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CAT4104
Example of Ordering Information (Note 6)
4.
5.
6.
7.
8.
Prefix
Device #
Suffix
CAT
4104
V
−G
T3
Company ID
(Optional)
Product Number
4104
Package
V: SOIC
VP2: TDFN
Lead Finish
G: NiPdAu
Tape & Reel (Note 8)
T: Tape & Reel
3: 3,000 / Reel
All packages are RoHS−compliant (Lead−free, Halogen−free).
The standard plated finish is NiPdAu.
The device used in the above example is a CAT4104V−GT3 (SOIC, NiPdAu, Tape & Reel, 3,000/Reel).
For additional temperature options, please contact your nearest ON Semiconductor Sales office.
For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging
Specifications Brochure, BRD8011/D.
ON Semiconductor and
are registered trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes without further notice
to any products herein. SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does SCILLC assume any liability
arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages.
“Typical” parameters which may be provided in SCILLC data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All
operating parameters, including “Typicals” must be validated for each customer application by customer’s technical experts. SCILLC does not convey any license under its patent rights
nor the rights of others. SCILLC products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications
intended to support or sustain life, or for any other application in which the failure of the SCILLC product could create a situation where personal injury or death may occur. Should
Buyer purchase or use SCILLC products for any such unintended or unauthorized application, Buyer shall indemnify and hold SCILLC and its officers, employees, subsidiaries, affiliates,
and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death
associated with such unintended or unauthorized use, even if such claim alleges that SCILLC was negligent regarding the design or manufacture of the part. SCILLC is an Equal
Opportunity/Affirmative Action Employer. This literature is subject to all applicable copyright laws and is not for resale in any manner.
PUBLICATION ORDERING INFORMATION
LITERATURE FULFILLMENT:
Literature Distribution Center for ON Semiconductor
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Phone: 303−675−2175 or 800−344−3860 Toll Free USA/Canada
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For additional information, please contact your local
Sales Representative
CAT4104/D
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