CAT4004 D

CAT4004
4-Channel Constant Current
LED Driver with EZDimt
Description
The CAT4004 provides four matched low dropout current sources to
drive LEDs. An external resistor on RSET sets the current in the LED
channels. Each LED channel includes an individual control loop
allowing the device to handle a wide range of LED forward voltages
while still maintaining tight current matching.
The EN/DIM logic inputs supports device enable and a digital
dimming interface for current setting of all LEDs. Six different current
dimming ratios are available.
The device is aimed at “direct drive” battery applications. It is
required that the battery or voltage source have enough headroom to
drive the LED forward voltage and current sink (>150 mV).
The device is available in a tiny 8−lead TDFN 2 mm x 3 mm
package with a max height of 0.8 mm.
Features
•
•
•
•
•
•
•
•
•
Four LED Current Sinks with Tight Matching
Low Dropout Driver 130 mV at 30 mA
No Switching Noise
Shutdown Current < 1 mA
LED Current set by External Resistor
Dimming via 1−wire EZDimt Interface
Thermal Shutdown Protection
8−lead 2 mm x 3 mm TDFN Package
These Devices are Pb−Free, Halogen Free/BFR Free and are RoHS
Compliant
Applications
•
•
•
•
LCD Display Backlight
Cellular Phones
Digital Still Cameras
Handheld Devices
TDFN−8
VP2 SUFFIX
CASE 511AK
PIN CONNECTIONS
EN/DIM
GND
20 mA
CIN
LED1
LED2 LED3 LED4
VIN
One wire
programming
EN/DIM
VIN
RSET
LED4
LED1
LED2
LED3
(Top View)
MARKING DIAGRAMS
FXA
XXX
YM
HAA
XXX
YM
FX = CAT4004VP2−T3
HA = CAT4004VP2−GT3
A = Assembly Location
XXX = Last Three Digits of Assembly Lot Number
Y = Production Year (Last Digit)
M = Production Month (1−9, A, B, C)
Device
1 mF
1
ORDERING INFORMATION
VIN
2.4 V
to
5.5 V
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Package
Shipping
CAT4004VP2−T3
(Note 1)
TDFN−8
(Pb−Free)
3,000/
Tape & Reel
CAT4004VP2−GT3
(Note 2)
TDFN−8
(Pb−Free)
3,000/
Tape & Reel
1. Matte−Tin Plated Finish (RoHS−compliant).
2. NiPdAu Plated Finish (RoHS−compliant).
CAT4004
RSET
RSET
3.8 kW
GND
Figure 1. Typical Application Circuit
© Semiconductor Components Industries, LLC, 2010
March, 2010 − Rev. 2
1
Publication Order Number:
CAT4004/D
CAT4004
Table 1. ABSOLUTE MAXIMUM RATINGS
Parameter
Rating
Unit
6
V
VIN + 0.7
V
Storage Temperature Range
−65 to +160
°C
Junction Temperature Range
−40 to +150
°C
300
°C
VIN, LEDx, RSET
EN/DIM Voltage
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
2.4 to 5.5
V
Ambient Temperature Range
−40 to +85
°C
0 to 40
mA
ILED per LED pin
NOTE: Typical application circuit with external components is shown on page 1.
Table 3. ELECTRICAL OPERATING CHARACTERISTICS
(over recommended operating conditions unless specified otherwise) VIN = 4.0 V, EN = High, TAMB = 25°C
Name
Symbol
IQ
Quiescent Current
IQSHDN
Shutdown Current
Conditions
Min
No load, RSET = Float
No load, RSET = 4.8 kW
Typ
0.6
1.0
VEN = 0 V
ILED−ACC
LED Current Accuracy
1 mA ≤ ILED ≤ 40 mA
ILED−DEV
LED Channel Matching
I LED * I LEDAVG
Max
mA
1
±1
mA
%
±1
−5
Units
+5
%
I LED
VDOUT
REN/DIM
VHI
VLO
Dropout Voltage
ILED = 30 mA
EN/DIM Pin
− Internal pull−down resistor
− Logic High Level
− Logic Low Level
130
mV
100
kW
V
V
1.3
0.4
TSD
Thermal Shutdown
150
°C
THYS
Thermal Hysteresis
20
°C
VUVLO
Undervoltage lockout (UVLO) threshold
1.8
V
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CAT4004
Table 4. RECOMMENDED EN/DIM TIMING
(For 2.4 ≤ VIN ≤ 5.5 V, over full ambient temperature range −40°C to +85°C.)
Name
Symbol
TSETUP
Conditions
Min
Typ
Max
Units
EN/DIM setup from shutdown
10
TLO
EN/DIM program low time
0.2
THI
EN/DIM program high time
0.2
ms
EN/DIM low time to shutdown
1.5
ms
TPWRDWN
TLED
LED current settling time
ms
100
ms
40
TSETUP
ms
TPWRDWN
THI
EN/DIM
TLED
TLO
100%
100%
50%
LED
Current
25%
Shutdown
12.5% 6.25%
3.12%
Shutdown
Figure 2. EN/DIM Dimming Timing Diagram
EN/DIM
Number of Pulses (Note 3)
RSET Gain
LED Current
LOW
Shutdown mode
Zero
Transitions HIGH
132
132 x 0.6 V/RSET
1st
66
66 x 0.6 V/RSET
2nd
33
33 x 0.6 V/RSET
3rd
16.5
16.5 x 0.6 V/RSET
4th
8.25
8.25 x 0.6 V/RSET
5th
4.125
4.125 x 0.6 V/RSET
6th
132
132 x 0.6 V/RSET
xth
Device will keep cycling through gain selection
GAIN x 0.6 V/RSET
3. The gain is changed on the rising edges of the EN/DIM input.
LED Current Selection
At power−up, the initial LED current is set to full scale
(100% brightness) by the external resistor RSET as follows:
LED current + 132
input signal, as shown on Figure 2. On each consecutive
pulse rising edge, the LED current is divided by half to 50%,
then 25%, 12.5%, 6.25% and 3.125% dimming levels.
Pulses faster than the minimum TLO may be ignored and
filtered by the device. Pulses longer than the maximum TLO
may shutdown the device.
The LED driver enters a “zero current” shutdown mode if
EN/DIM is held low for 1.5 ms or more.
0.6 V
R SET
The EN/DIM pin has two primary functions. One function
enables and disables the device. The other function is LED
current dimming with six different levels by pulsing the
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CAT4004
TYPICAL PERFORMANCE CHARACTERISTICS
(VIN = 4 V, VF = 3.3 V, IOUT = 80 mA (4 LEDs at 20 mA), CIN = 1 mF, TAMB = 25°C unless otherwise specified.)
1.4
1.0
0.8
0.6
2.5
3.0
3.5
4.0
4.5
5.0
1.2
1.0
0.8
0.6
5.5
0
40
80
120
TEMPERATURE (°C)
Figure 3. Quiescent Current vs. Input Voltage
Figure 4. Quiescent Current vs. Temperature
1.0
10
0.8
8
0.6
0.4
0.2
0
−0.2
−0.4
−0.6
−0.8
−1.0
−40
INPUT VOLTAGE (V)
LED CURRENT CHANGE (%)
LED CURRENT CHANGE (%)
QUIESCENT CURRENT (mA)
1.2
3.0
3.5
4.0
4.5
5.0
5.5
6
4
2
0
−2
−4
−6
−8
−10
−40
0
40
80
INPUT VOLTAGE (V)
TEMPERATURE (°C)
Figure 5. LED Current Change vs. Input
Voltage
Figure 6. LED Current Change vs.
Temperature
40
LED CURRENT (mA)
QUIESCENT CURRENT (mA)
1.4
30
20
10
0
0
5
10
15
RSET (kW)
Figure 7. LED Current vs. RSET Resistor
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4
20
120
CAT4004
TYPICAL PERFORMANCE CHARACTERISTICS
0.7
0.7
0.6
0.6
RSET VOLTAGE (V)
RSET VOLTAGE (V)
(VIN = 4 V, VF = 3.3 V, IOUT = 80 mA (4 LEDs at 20 mA), CIN = 1 mF, TAMB = 25°C unless otherwise specified.)
0.5
0.4
0.3
0.4
0.3
2.0
2.5
3.0
3.5
4.0
4.5
5.0
0.2
−40
5.5
80
120
Figure 8. RSET Pin Voltage vs. Input Voltage
Figure 9. RSET Pin Voltage vs. Temperature
30
30
LED CURRENT (mA)
40
20
10
0
40
TEMPERATURE (°C)
40
0
0
INPUT VOLTAGE (V)
0.5
1.0
1.5
2.0
2.5
3.0
20
10
0
3.5
0
50
100
150
200
250
LED PIN VOLTAGE (V)
LED PIN VOLTAGE (mV)
Figure 10. LED Current vs. LED Pin Voltage
Figure 11. Dropout Characteristics
100
90
EFFICIENCY (%)
LED CURRENT (mA)
0.2
0.5
80
70
60
50
5.0
4.5
4.0
3.5
3.0
2.5
INPUT VOLTAGE (V)
Figure 12. Efficiency vs. Input Voltage
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2.0
300
CAT4004
TYPICAL PERFORMANCE CHARACTERISTICS
(VIN = 4 V, VF = 3.3 V, IOUT = 80 mA (4 LEDs at 20 mA), CIN = 1 mF, TAMB = 25°C unless otherwise specified.)
Figure 13. Power Up Waveform
Figure 14. Power Down Waveform
Figure 15. Line Transient Waveform
4 V to 5.5 V
Figure 16. Dimming Waveform 80 mA to 40 mA
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CAT4004
Table 5. PIN DESCRIPTIONS
Pin #
Name
Function
1
EN/DIM
2
GND
Ground reference
3
LED1
LED1 cathode terminal
4
LED2
LED2 cathode terminal
5
LED3
LED3 cathode terminal
6
LED4
LED4 cathode terminal
7
RSET
RSET external LED mirror gain 128
8
VIN
Device supply input, connect to battery or supply
TAB
TAB
Connect to GND on the PCB
Device enable (active high) and dimming control
Pin Function
VIN is the supply pin for the device logic. A small 1 mF
ceramic bypass capacitor is required between the VIN pin
and ground near the device. The operating input voltage
range is from 2.5 V to 5.5 V. Whenever the input supply falls
below the under−voltage threshold (1.8 V), all the LED
channels are disabled and the device enters shutdown mode.
EN/DIM is the enable and one wire dimming input for all
LED channels. Levels of logic high and logic low are set at
1.3 V and 0.4 V respectively. When EN/DIM is initially
taken high, the device becomes enabled and all LED
currents are set to the full scale according to the resistor
RSET. To place the device into “zero current” shutdown
mode, the EN/DIM pin must be held low for at least 1.5 ms.
LED1 to LED4 provide the internal regulated current for
each of the LED cathodes. There pins enter a high
impedance zero current state whenver the device is placed
in shutdown mode.
RSET is connected to the resistor (RSET) to set the full scale
current for the LEDs. The voltage at this pin is regulated to
0.6 V. The ground side of the external resistor should be star
connected back to the GND of the PCB. In shutdown mode,
RSET beomes high impedance.
GND is the ground reference for the device. The pin must be
connected to the ground plane on the PCB.
TAB 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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CAT4004
Block Diagram
LED4
LED3
Undervoltage
Lockout
LED2
VIN
LED1
VIN
Reference
Voltage
RSET
Current
Setting DAC
Serial
Interface
EN/DIM
4 Current Sink
Regulators
Register
100 kW
GND
Figure 17. CAT4004 Functional Block Diagram
Basic Operation
The CAT4004 uses four tightly matched current sinks to
accurately regulate LED current in each channel
proportional to the current sourced from the RSET pin.
I LED + GAIN
power−up is 132. Tight current regulation for all channels is
possible over a wide range of input and LED voltages due to
independent current sensing circuitry on each channel.
Each LED channel needs a minimum of 150 mV
headroom to sink constant regulated current. If the input
supply falls below 1.8 V, the under−voltage lockout circuit
disables all LED channels and resets the circuit to default
values. Any unused LED channels should be left open.
0.6 V
R SET
There are six different gain settings for LED brightness
that can be set through the EN/DIM pin. The default gain on
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CAT4004
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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CAT4004
Example of Ordering Information (Note 6)
4.
5.
6.
7.
8.
Prefix
Device #
Suffix
CAT
4004
VP2
−G
T3
Company ID
(Optional)
Product Number
4004
Package
VP2: TDFN 2 x 3 mm
Lead Finish
G: NiPdAu
Blank: Matte−Tin (Note 7)
Tape & Reel (Note 8)
T: Tape & Reel
3: 3,000 / Reel
All packages are RoHS−compliant (Lead−free, Halogen−free).
The standard lead finish is NiPdAu.
The device used in the above example is a CAT4004VP2−GT3 (TDFN, NiPdAu Plated Finish, Tape & Reel, 3,000/Reel).
For Matte−Tin package option, 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
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PUBLICATION ORDERING INFORMATION
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For additional information, please contact your local
Sales Representative
CAT4004/D
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