CAT3614
4-Channel 1-Wire LED
Driver in 3 x 3 mm Package
Description
The CAT3614 is a high efficiency 1x/1.5x fractional charge pump
with programmable dimming current in four LED channels. To ensure
uniform brightness in LCD backlight applications, each LED channel
delivers an accurate regulated current.
Low noise and input ripple is achieved by operating at a constant
switching frequency of 1 MHz which allows the use of small external
ceramic capacitors. The 1x/1.5x fractional charge pump supports a
wide range of input voltages from 3 V to 5.5 V with efficiency up to
91%, and is ideal for Li−Ion battery powered devices.
The EN/DIM logic input provides a 1−wire EZDimt interface for
dimming control of the LEDs. When enabled, a series of clock pulses
reduces the LED brightness in 1 mA steps on each negative going
edge. Currents from 0 mA to 31 mA are supported.
The device is available in the tiny 12−pad TDFN 3 x 3 mm package
with a max height of 0.8 mm.
Features
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TDFN−12
HV2 SUFFIX
CASE 511AN
PIN CONNECTIONS
VIN
C1+
C1−
C2−
C2+
GND
(Top View)
1
VOUT
EN/DIM
LED4
LED3
LED2
LED1
•
•
•
•
•
•
•
•
•
•
•
•
•
Drives up to 4 LED Channels
1−wire EZDimt Programmable LED Current
Accurate 1 mA Dimming Level
Power Efficiency up to 91%
Fractional Pump 1x/1.5x
Low Noise Input Ripple
Fixed High Frequency Operation 1 MHz
“Zero” Current Shutdown Mode
Soft Start and Current Limiting
Short Circuit Protection
Thermal Shutdown Protection
TDFN 12−pad 3 mm x 3 mm Package
These Devices are Pb−Free, Halogen Free/BFR Free and are RoHS
Compliant
LCD Display Backlight
Cellular Phones
Digital Still Cameras
Handheld Devices
MARKING DIAGRAM
HAAA
AXXX
YWW
HAAC
AXXX
YWW
HAAA = CAT3614HV2-T2
HAAC = CAT3614HV2-GT2
A = Assembly Location
XXX = Last Three Digits of Assembly Lot Number
Y = Production Year (Last Digit)
WW = Production Week (Two Digit)
Applications
•
•
•
•
ORDERING INFORMATION
Device
CAT3614HV2−T2
(Note 1)
CAT3614HV2−GT2
(Note 2)
Package
TDFN−12
(Pb−Free)
TDFN−12
(Pb−Free)
Shipping
2,000/
Tape & Reel
2,000/
Tape & Reel
1. Matte−Tin Plated Finish (RoHS−compliant).
2. NiPdAu Plated Finish (RoHS−compliant).
©
Semiconductor Components Industries, LLC, 2010
April, 2010
−
Rev. 2
1
Publication Order Number:
CAT3614/D
CAT3614
1
mF
V
IN
3 V to
5.5 V
C
IN
1
mF
1
mF
V
OUT
C
OUT
1
mF
20 mA
C1+ C1− C2+ C2−
VIN
VOUT
CAT3614
LED1
LED2
LED3
LED4
ENABLE/
DIMMING
EN/DIM
GND
Figure 1. Typical Application Circuit
NOTE:
Unused LED channels must be connected to VOUT.
Table 1. ABSOLUTE MAXIMUM RATINGS
Parameter
VIN, LEDx voltage
VOUT, C1±, C2± voltage
EN/DIM voltage
Storage Temperature Range
Junction Temperature Range
Lead Temperature
Rating
6
7
V
IN
+ 0.7 V
−65
to +160
−40
to +150
300
Unit
V
V
V
°C
°C
°C
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
VIN
Ambient Temperature Range
I
LED
per LED pin
Total Output Current
NOTE:
Typical application circuit with external components is shown above.
Range
3 to 5.5
−40
to +85
0 to 31
0 to 124
Unit
V
°C
mA
mA
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2
CAT3614
Table 3. ELECTRICAL OPERATING CHARACTERISTICS
V
IN
= 3.6 V, EN = High, ambient temperature of 25°C (over recommended operating conditions unless specified otherwise).
Symbol
I
Q
I
QSHDN
I
LED−ACC
I
LED−DEV
R
OUT
F
OSC
I
SC_MAX
I
IN_MAX
I
EN/DIM
V
HI
V
LO
T
SD
T
HYS
V
UVLO
Parameter
Quiescent Current
Shutdown Current
LED Current Accuracy
LED Channel Matching
Output Resistance (open loop)
Charge Pump Frequency
Output short circuit Current Limit
Input Current Limit
EN/DIM Pin
−
Input Leakage
−
Logic High Level
−
Logic Low Level
Thermal Shutdown
Thermal Hysteresis
Undervoltage lock out (UVLO) threshold
V
OUT
< 0.5 V
1x mode, V
OUT
> 1 V
Conditions
1x mode, no load
1.5x mode, no load
V
EN
= 0 V
1 mA
≤
I
LED
≤
31 mA
(I
LED
−
I
LEDAVG
) / I
LEDAVG
1x mode, I
OUT
= 100 mA
1.5x mode, I
OUT
= 100 mA
0.8
30
200
−1
1.3
145
10
1.7
165
20
2
±3
±3
0.4
2.6
1
60
300
Min
0.3
1
Typ
0.5
3
Max
1
8
1
±8
±7
1
7
1.3
100
600
1
0.4
175
30
2.4
Unit
mA
mA
%
%
W
MHz
mA
mA
mA
V
V
°C
°C
V
Table 4. RECOMMENDED EN/DIM TIMING
(For 3 V
≤
V
IN
≤
5.5 V, over full ambient temperature range
−40
to +85°C.)
Symbol
T
SETP
T
LO
T
HI
T
OFF
T
D
T
DEC
Parameter
EN/DIM setup from shutdown
EN/DIM program low time
EN/DIM program high time
EN/DIM low time to shutdown
LED current enable
LED current decrement
T
SETP
EN/DIM
T
D
T
LO
T
DEC
31 mA 30 mA
29 mA
LED
Current
Shutdown
1 mA
0 mA
Shutdown
31 mA
T
HI
Conditions
Min
10
0.3
0.3
1.5
40
0.1
T
OFF
200
Typ
Max
Unit
ms
ms
ms
ms
ms
ms
Figure 2. LED Dimming Timing Diagram
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3
CAT3614
TYPICAL CHARACTERISTICS
(V
IN
= 3.6 V, I
OUT
= 80 mA (4 LEDs at 20 mA), C
1
= C
2
= C
IN
= C
OUT
= 1
mF,
T
AMB
= 25°C unless otherwise specified.)
100
20 mA per LED
90
1x mode
EFFICIENCY (%)
EFFICIENCY (%)
80
70
10 mA per LED
60
50
40
4.2
4.0
3.8
3.6
90
80
70
60
50
3.2
3.0
40
0
VIN = 3.2 V (1.5x Mode)
VIN = 4 V (1x Mode)
100
1.5x mode
3.4
25
50
75
100
125
INPUT VOLTAGE (V)
TOTAL LED CURRENT (mA)
Figure 3. Efficiency vs. Input Voltage (4 LEDs)
0.8
QUIESCENT CURRENT (mA)
QUIESCENT CURRENT (mA)
0.8
Figure 4. Efficiency vs. Total LED Current
(4 LEDs)
0.6
0.6
0.4
4 LEDs OFF
0.2
0.4
4 LEDs OFF
0.2
0
3.0
3.2
3.4
3.6
3.8
4.0
4.2
0
−40
0
40
TEMPERATURE (°C)
80
120
INPUT VOLTAGE (V)
Figure 5. Quiescent Current vs. Input Voltage
(1x Mode)
6
QUIESCENT CURRENT (mA)
5
4
3
2
4 LEDs OFF
1
0
QUIESCENT CURRENT (mA)
6
5
4
3
2
Figure 6. Quiescent Current vs. Temperature
(1x Mode)
4 LEDs OFF
1
0
−40
3.0
3.2
3.4
3.6
3.8
4.0
4.2
0
40
TEMPERATURE (°C)
80
120
INPUT VOLTAGE (V)
Figure 7. Quiescent Current vs. Input Voltage
(1.5x Mode)
Figure 8. Quiescent Current vs. Temperature
(1.5x Mode)
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4
CAT3614
TYPICAL CHARACTERISTICS
(V
IN
= 3.6 V, I
OUT
= 80 mA (4 LEDs at 20 mA), C
1
= C
2
= C
IN
= C
OUT
= 1
mF,
T
AMB
= 25°C unless otherwise specified.)
5
LED CURRENT CHANGE (%)
3
2
1
0
−1
−2
−3
−4
−5
3.0
3.2
3.4
3.6
3.8
4.0
4.2
1.5x Mode
1x Mode
LED CURRENT CHANGE (%)
4
5
4
3
2
1
0
−1
−2
−3
−4
−5
−40
−20
0
20
40
60
80
INPUT VOLTAGE (V)
TEMPERATURE (°C)
Figure 9. LED Current Change vs. Input
Voltage
1.3
CLOCK FREQUENCY (MHz)
CLOCK FREQUENCY (MHz)
1.2
1.1
1.0
4 LEDs at 20 mA
0.9
0.8
0.7
1.3
1.2
1.1
1.0
0.9
0.8
0.7
−40
Figure 10. LED Current Change vs.
Temperature
3.0
3.2
3.4
3.6
3.8
4.0
0
40
TEMPERATURE (°C)
80
120
INPUT VOLTAGE (V)
Figure 11. Oscillator Frequency vs. Input
Voltage
1.0
OUTPUT RESISTANCE (W)
0.8
0.6
OUTPUT RESISTANCE (W)
4.0
3.5
3.0
2.5
2.0
1.5
1.0
Figure 12. Oscillator Frequency vs.
Temperature
0.4
0.2
0
3.0
3.2
3.4
3.6
3.8
4.0
4.2
3.0
3.2
3.4
3.6
3.8
4.0
4.2
INPUT VOLTAGE (V)
INPUT VOLTAGE (V)
Figure 13. Output Resistance vs. Input Voltage
(1x Mode)
Figure 14. Output Resistance vs. Input Voltage
(1.5x Mode)
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