CAT3636
6-Channel Quad-Mode
TM
Fractional LED Driver in TQFN3x3
FEATURES
High efficiency 1.33x charge pump
Quad-mode charge pump: 1x, 1.33x, 1.5x, 2x
Drives up to 6 LEDs at 32mA each
1-wire EZDim
TM
LED current programming
Power efficiency up to 92%
Low noise input ripple in all modes
“Zero” current shutdown mode
Soft start and current limiting
Short circuit protection
Thermal shutdown protection
Tiny 3mm x 3mm, 16-lead TQFN package
DESCRIPTION
The CAT3636 is a high efficiency quad-mode fractional
charge pump that can drive up to six LEDs
programmable by a one wire digital interface. The
inclusion of a 1.33x fractional charge pump mode
increases device efficiency by up to 10% over traditional
1.5x charge pumps with no added external capacitors.
Low noise input ripple is achieved by operating at a
constant switching frequency which allows the use of
small external ceramic capacitors. The multi-fractional
charge pump supports a wide range of input voltages
from 2.5V to 5.5V.
The EN/SET logic input functions as a chip enable and a
“1-wire” addressable interface for control and current
setting of all LEDs. Three groups of two LEDs can be
configured with independent LED currents between
0.25mA and 32mA.
The device is available in a tiny 16-lead TQFN 3mm x
3mm package with a max height of 0.8mm.
The 1.33x charge pump with two fly capacitors is a
patent pending architecture exclusive to Catalyst
Semiconductor.
APPLICATIONS
LCD Display Backlight
Color RGB LEDs
Cellular Phones
Digital Still Cameras
Handheld Devices
ORDERING INFORMATION
Part
Package
Number
CAT3636 TQFN-16
HV3-T2 3x3 Green*
* Lead Finish: Matte-Tin
Quantity
per Reel
2000
Package
Marking
JAAA
For Ordering Information details, see page 15.
PIN CONFIGURATION
TYPICAL APPLICATION CIRCUIT
© 2007 Catalyst Semiconductor, Inc.
Characteristics subject to change without notice
1
Doc. No. 5020 Rev. C
CAT3636
ABSOLUTE MAXIMUM RATINGS
Parameter
VIN, LEDx, C1±, C2± voltage
VOUT Voltage
EN/SET Voltage
Storage Temperature Range
Junction Temperature Range
(1)
Lead Temperature
Rating
6
7
VIN + 0.7V
-65 to +160
-40 to +125
300
Unit
V
V
V
°C
°C
°C
RECOMMENDED OPERATING CONDITIONS
Parameter
Range
Unit
VIN
2.5 to 5.5
V
Ambient Temperature Range
(1)
-40 to +85
°C
I
LED
per LED pin
0 to 32
mA
Total Output Current
0 to 192
mA
Note:
(1) Package thermal resistance is below 50°C/W when mounted on FR4 board.
Typical application circuit with external components is shown on page 1.
ELECTRICAL OPERATING CHARACTERISTICS
(over recommended operating conditions unless specified otherwise) VIN = 3.6V, EN = High, T
AMB
= 25°C
Symbol
I
Q
I
QSHDN
I
LED-ACC
I
LED-DEV
Name
Quiescent Current
Shutdown Current
LED Current Accuracy
LED Channel Matching
Conditions
1x mode, VIN = 4.2V
1.33 x mode, VIN = 3.3V
1.5x mode, VIN = 2.8V
2x mode, VIN = 2.5V
V
EN
= 0V
1mA
≤
I
LED
≤
31mA
I
LED
−
I
LEDAVG
I
LED
1x mode, I
OUT
= 100mA
1.33x mode, I
OUT
= 100mA
1.5x mode, I
OUT
= 100mA
2x mode, I
OUT
= 100mA
1.33x and 2x mode
1.5x mode
V
OUT
< 0.5V
Min
Typ
1.5
2.8
3.7
3.8
±3
±1
0.5
4.5
3.5
6
0.8
1.1
80
150
VIN - Highest LED V
F
V
OUT
> 1V
1.3
0.4
150
20
2
400
500
450
100
Max
Units
mA
mA
mA
mA
µA
%
%
Ω
Ω
Ω
Ω
MHz
MHz
mA
mV
mV
µs
mA
kΩ
V
V
°C
°C
V
1
R
OUT
F
OSC
I
SC_MAX
LED
TH
V
HYS
T
DF
I
IN_MAX
R
EN/DIM
V
HI
V
LO
T
SD
T
HYS
V
UVLO
Output Resistance (open loop)
Charge Pump Frequency
Output short circuit Current Limit
1x to 1.33x or 1.33x to 1.5x or
1.5x to 2x Transition Thresholds at any
LEDxx pin
1.33x to 1x Transition Hysteresis
Transition Filter Delay
Input Current Limit
EN/DIM Pin
•
Internal Pull-down Resistor
•
Logic High Level
•
Logic Low Level
Thermal Shutdown
Thermal Hysteresis
Undervoltage lockout (UVLO) threshold
0.6
0.8
1.1
1.4
Doc. No. 5020 Rev. C
2
© 2007 Catalyst Semiconductor, Inc.
Characteristics subject to change without notice
CAT3636
RECOMMENDED EN/SET TIMING
Symbol
For 2.5
≤
VIN
≤
5.5V, over full ambient temperature range -40 to +85ºC.
T
SETUP
10
T
LO
0.2
T
HI
0.2
T
OFF
1.5
T
DATADELAY
500
1000
T
RESETDELAY
2
Note:
(1) If the Max value is exceeded then the user should wait 2ms before trying to program the device again.
Name
EN/SET setup from shutdown
EN/SET program low time
EN/SET program high time
EN/SET low time to shutdown
EN/SET Delay to DATA
EN/SET Delay High to ADDRESS
Conditions
Min
Typ
Max
100
(1)
100
100
Units
μs
μs
μs
ms
μs
ms
Figure 1. EN/SET One Wire Addressable Timing Diagram
© 2007 Catalyst Semiconductor, Inc.
Characteristics subject to change without notice
3
Doc. No. 5020 Rev. C
CAT3636
TYPICAL PERFORMANCE CHARACTERISTICS
VIN = 3.6V, I
OUT
= 120mA (6 LEDs at 20mA), C
IN
= C
OUT
= C1 = C2 = 1μF, T
AMB
= 25°C unless otherwise specified.
Efficiency vs. Input Voltage
100
90
EFFICIENCY [%]
80
70
60
50
IOUT = 40mA
40
4.5
4.0
3.5
3.0
2.5
INPUT VOLTAGE [V]
2.0
V
F
= 3.3V
1x
2x
1.33x
1.5x
Efficiency vs. Li-Ion Voltage
100
90
EFFICIENCY [%]
80
70
60
50
40
4.2
4.0 3.8 3.6 3.4 3.2
INPUT VOLTAGE [V]
3.0
Traditional 1.5x
Charge Pump
V
F
= 3.3V
V
F
= 3.0V
LED Current Change vs. Input Voltage
LED CURRENT VARIATION [%] .
10
8
6
4
2
0
-2
-4
-6
-8
-10
5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0
INPUT VOLTAGE [V]
V
F
= 3.3V
LED Current Change vs. Temperature
LED CURRENT VARIATION [%] .
10
8
6
4
2
0
-2
-4
-6
-8
-10
-40
-20
0
20 40
60
TEMPERATURE [°C]
80
Quiescent Current vs. Input Voltage
6.0
QUIESCENT CURRENT [mA]
5.0
4.0
3.0
2.0
1.0
0.0
5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0
INPUT VOLTAGE [V]
V
F
= 3.3V
Doc. No. 5020 Rev. C
4
© 2007 Catalyst Semiconductor, Inc.
Characteristics subject to change without notice
CAT3636
TYPICAL PERFORMANCE CHARACTERISTICS
VIN = 3.6V, I
OUT
= 120mA (6 LEDs at 20mA), C
IN
= C
OUT
= C1 = C2 = 1μF, T
AMB
= 25°C unless otherwise specified.
Switching Frequency vs. Temperature
SWITCHING FREQUENCY [MHz]
1.2
1.1
1.0
0.9
0.8
0.7
0.6
-40
-20
0
20 40 60
TEMPERATURE [°C]
80
1.33x, 2x Mode
1.5x Mode
OUTPUT RESISTANCE [Ω] .
Output Resistance vs. Input Voltage
10
V
F
= 3.3V
8
6
4
2
0
5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0
INPUT VOLTAGE [V]
1.5x
2x
1.33x
1x
Power Up in 1x Mode
Power Up in 1.33x Mode
Power Up in 1.5x Mode
Power Up in 2x Mode
© 2007 Catalyst Semiconductor, Inc.
Characteristics subject to change without notice
5
Doc. No. 5020 Rev. C