LTC3207/LTC3207-1
600mA Universal
Multi-Output LED/CAM Driver
FEATURES
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■
DESCRIPTION
The LTC
®
3207/LTC3207-1 are highly integrated multi-display
LED drivers. The device contains a high-efficiency, low-noise
charge pump to provide power to 12 universal LED current
sources and one camera LED current source. The LTC3207/
LTC3207-1 require only five small ceramic capacitors to
form a complete LED power supply and current controller.
In addition there are two I
2
C addresses available.
The display currents are set by an internal precision cur-
rent reference. Independent dimming, On/Off, blinking
and gradation control for all universal current sources is
achieved via the I
2
C serial interface. 6-bit linear DACs are
available for adjusting brightness levels for each universal
LED current source. The CAM current source has a 4-bit
linear DAC to adjust brightness.
The LTC3207/LTC3207-1 charge pumps optimize efficiency
based on the voltage across the LED current sources. The
device powers-up in 1x mode and will automatically switch
to boost mode whenever any enabled LED current source
begins to enter dropout. The first dropout switches the
IC into 1.5x mode and a subsequent dropout switches
the LTC3207/LTC3207-1 into 2x mode. The device resets
to 1x mode whenever a data register is updated via the
I
2
C port.
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners. Protected by U.S. Patents,
including 6411531.
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Low Noise, Multi-Mode Charge Pump (1x, 1.5x, 2x)
Provides Up to 91% Efficiency
Slew Limited Switching Reduces Conducted and
Radiated Noise (EMI)
Up to 600mA Total Output Current
Twelve 28mA Universal Current Sources with
64-Step Linear Brightness Control
425mA CAM LED Current Source with 16-Step
Linear Brightness Control and 2-Second High
Current Safety Timer
Independent On/Off, Brightness Level, Blinking and
Gradation Control for Each Current Source Using
2-Wire I
2
C
TM
Interface
Internal Current Reference
Two I
2
C Addresses are Available
(LTC3207 00110110, LTC3207-1 00110100)
Configurable ENU Pin for Asynchronous LED
On/Off Control
Automatic or Forced Mode Switching
Internal Soft-Start Limits Inrush Current
Short-Circuit/Thermal Protection
4mm × 4mm 24-Pin QFN Plastic Package
APPLICATIONS
■
Video Phones with QVGA
+
Displays
TYPICAL APPLICATION
4-LED MAIN, 2-LED SUB, Dual RGB and Camera Light
C2
2.2µF
C3
2.2µF
V
BAT
C1
2.2µF
C1P C1M C2P C2M
V
BAT
CPO
LTC3207/LTC3207-1
DV
CC
C4
4.7µF
MAIN
SUB
RGB
RGB
CAM
DV
CC
0.1µF
ULED1-12
I
2
C
ENABLE DISABLE
LOW HI
2
SCL/SDA
ENU
CAMHL
GND
CAM
12
3207 TA01
3207fc
1
LTC3207/LTC3207-1
ABSOLUTE MAXIMUM RATINGS
(Notes 1, 4)
PIN CONFIGURATION
TOP VIEW
V
BAT
C1M
C2M
18 ULED12
17 ULED11
25
16 ULED10
15 ULED9
14 ULED8
13 ULED7
7
CAM
8
CAMHL
9 10 11 12
ULED6
DV
CC
SDA
SCL
ENU
C1P
CPO 1
ULED1 2
ULED2 3
ULED3 4
ULED4 5
ULED5 6
C2P
V
BAT
, DV
CC
, CPO ........................................... –0.3V to 6V
ULED1 to ULED12, CAM .............................. –0.3V to 6V
SDA, SCL, ENU, CAMHL .............–0.3V to (DV
CC
+ 0.3V)
I
CPO
Continuous (Note 3) ........................................350mA
Pulsed at 10% Duty Cycle ................................600mA
I
CAM
Continuous (Note 3) ........................................300mA
Pulsed at 10% Duty Cycle ................................460mA
CPO Short-Circuit Duration .............................. Indefinite
Operating Temperature Range (Note 2).... –40°C to 85°C
Storage Temperature Range................... –65°C to 125°C
24 23 22 21 20 19
UF PACKAGE
24-LEAD (4mm × 4mm) PLASTIC QFN
T
JMAX
= 125°C,
θ
JA
= 40°C/W
EXPOSED PAD (PIN 25) IS GND, MUST BE SOLDERED TO PCB
ORDER INFORMATION
LEAD FREE FINISH
LTC3207EUF#PBF
LTC3207EUF-1#PBF
TAPE AND REEL
LTC3207EUF#TRPBF
LTC3207EUF-1#TRPBF
PART MARKING
3207
32071
PACKAGE DESCRIPTION
24-Lead (4mm × 4mm) Plastic QFN
24-Lead (4mm × 4mm) Plastic QFN
TEMPERATURE RANGE
–40°C to 85°C
–40°C to 85°C
Consult LTC Marketing for parts specified with wider operating temperature ranges.
Consult LTC Marketing for information on non-standard lead based finish parts.
For more information on lead free part marking, go to:
http://www.linear.com/leadfree/
For more information on tape and reel specifications, go to:
http://www.linear.com/tapeandreel/
ELECTRICAL CHARACTERISTICS
PARAMETER
V
BAT
Operating Voltage
I
VBAT
Operating Current
CONDITIONS
The
●
denotes the specifications which apply over the full operating
,
temperature range, otherwise specifications are at T
A
= 25°C. V
BAT
= 3.6V, DV
CC
= 3V, ENU = Hi, CAMHL = LO, C1 = C2 = C3 = 2.2
µ
F
,
C4 = 4.7
µ
F unless otherwise noted.
MIN
●
TYP
0.5
2.9
4.1
1
MAX
5.5
UNITS
V
mA
mA
mA
V
2.9
I
CPO
= 0, 1x Mode
I
CPO
= 0, 1.5x Mode
I
CPO
= 0, 2x Mode
●
DV
CC
UVLO Threshold
DV
CC
Operating Voltage
V
BAT
UVLO Threshold
V
BAT
Shutdown Current
DV
CC
Shutdown Current
Universal LED Current, 6-Bit Linear DACs, ULED = 1V
Full-Scale LED Current
Minimum (1LSB) LED Current
●
●
●
1.5
1.5
3.2
5.5
7
1
V
V
µA
µA
mA
mA
3207fc
24.2
27.5
0.436
31
2
LTC3207/LTC3207-1
ELECTRICAL CHARACTERISTICS
PARAMETER
LED Current Matching
LED Dropout Voltage
Blink Rate Period
ULED Up/Down Gradation Times
CONDITIONS
Any Two Outputs, 50% of FS
I
LED
= FS
REG15, D6 and D7
REG15, D4 and D5
●
●
The
●
denotes the specifications which apply over the full operating
,
temperature range, otherwise specifications are at T
A
= 25°C. V
BAT
= 3.6V, DV
CC
= 3V, ENU = Hi, CAMHL = LO, C1 = C2 = C3 = 2.2
µ
F
,
C4 = 4.7
µ
F unless otherwise noted.
MIN
TYP
2
180
1.25
2.5
0.24
0.45
0.48
0.9
0.96
●
MAX
UNITS
%
mV
s
s
s
s
s
s
s
s
mV
mA
mA
mV
s
Ω
Ω
Ω
V
V
1.8
7
425
29
V
OL
General Purpose Output Mode (GPO)
CAM LED Current, 4-Bit Linear DAC, CAM = 1V
Full-Scale LED Current
Minimum (1LSB) LED Current
LED Dropout Voltage
High Current Safety Timer
Charge Pump (CPO)
1x Mode Output Impedance
1.5x Mode Output Impedance
2x Mode Output Impedance
CPO Regulation Voltage
CLOCK Frequency
SDA, SCL, ENU, CAMHL
V
IL
V
IH
I
IH
I
IL
V
OL
Digital Output Low (SDA)
Serial Port Timing (Notes 6, 7)
t
SCL
t
BUF
t
HD,STA
t
SU,STA
t
SU,STO
t
HD,DAT(OUT)
t
HD,DAT(IN)
t
SU,DAT
t
LOW
t
HIGH
I
OUT
= 1mA, Single Output Enabled
I
LED
= FS
High Current Mode
450
2.1
0.6
V
BAT
= 3V, V
CPO
= 4.2V (Note 5)
V
BAT
= 3V, V
CPO
= 4.8V (Note 5)
1.5x Mode, I
CPO
= 20mA
2x Mode, I
CPO
= 20mA
●
3.6
4.1
4.55
5.05
0.65
0.85
1.05
0.3 • DV
CC
0.7 • DV
CC
–1
–1
0.12
1
1
0.4
MHz
V
V
µA
µA
V
●
●
SDA, SCL, ENU, CAMHL = DV
CC
SDA, SCL, ENU, CAMHL = 0V
I
PULLUP
= 3mA
●
●
●
Clock Operating Frequency
Bus Free Time Between Stop and Start Condition
Hold Time After (Repeated) Start Condition
Repeated Start Condition Setup Time
Stop Condition Setup Time
Output Data Hold Time
Input Data Hold Time
Data Setup Time
Clock Low Period
Clock High Period
1.3
0.6
0.6
0.6
0
0
100
1.3
0.6
400
kHz
µs
µs
µs
µs
900
ns
ns
ns
µs
µs
3207fc
3
LTC3207/LTC3207-1
ELECTRICAL CHARACTERISTICS
PARAMETER
t
f
t
r
t
SP
CONDITIONS
Clock Data Fall Time
Clock Data Rise Time
Spike Suppression Time
The
●
denotes the specifications which apply over the full operating
,
temperature range, otherwise specifications are at T
A
= 25°C. V
BAT
= 3.6V, DV
CC
= 3V, ENU = Hi, CAMHL = LO, C1 = C2 = C3 = 2.2
µ
F
,
C4 = 4.7
µ
F unless otherwise noted.
MIN
20
20
50
TYP
MAX
300
300
UNITS
ns
ns
ns
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2:
The LTC3207E/LTC3207E-1 are guaranteed to meet performance
specifications from 0°C to 85°C. Specifications over the –40°C to
85°C ambient operating temperature range are assured by design,
characterization and correlation with statistical process controls.
Note 3:
Based on long term current density limitations. Assumes operating
duty cycle of <10% under absolute maximum conditions for durations less
than 10 seconds.
Note 4:
This IC includes overtemperature protection that is intended
to protect the device during momentary overload conditions. Junction
temperature will exceed 125°C when overtemperature protection is active.
Continuous operation above the specified maximum operating junction
temperature may result in device degradation or failure.
Note 5:
1.5x mode output impedance is defined as (1.5V
BAT
– V
CPO
)/I
OUT
.
2x mode output impedance is defined as (2V
BAT
– V
CPO
)/I
OUT
.
Note 6:
All values are referenced to V
IH
and V
IL
levels.
Note 7:
Guaranteed by design.
TYPICAL PERFORMANCE CHARACTERISTICS
Mode Switch Dropout Times
V
BAT
= 3.6V
V
CPO
1V/DIV
1.5x
1x
2x
V
CPO
20mV/DIV
AC
COUPLED
T
A
= 25°C unless otherwise noted
2x Mode CPO Ripple
1.5x Mode CPO Ripple
V
CPO
20mV/DIV
AC
COUPLED
200µs/DIV
3207 G01
500ns/DIV
V
BAT
= 3.6V
I
CPO
= 200mA
C
CPO
= 4.7µF
3207 G02
500ns/DIV
V
BAT
= 3.6V
I
VCPO
= 200mA
C
CPO
= 4.7µF
3207 G03
1x Mode Switch Resistance
vs Temperature
0.80
0.75
SWITCH RESISTANCE (Ω)
0.70
0.65
0.60
0.55
0.50
0.45
0.40
–40
–15
35
TEMPERATURE (°C)
10
60
85
3207 G04
1.5x Mode Charge Pump Open-Loop
Output Resistance vs Temperature
(1.5V
BAT
-V
CPO
) / I
CPO
4.5
OPEN LOOP OUTPUT RESISTANCE (Ω)
4.3
4.1
3.9
3.7
3.5
3.3
3.1
2.9
2.7
2.5
–40
–15
35
10
TEMPERATURE (°C)
60
85
3207 G05
1.5x Mode CPO Voltage vs I
CPO
4.8
4.6
CPO VOLTAGE (V)
4.4
4.2
4.0
3.8
3.6
C2 = C3 = 2.2µF
C4 = 4.7µF
3.6V
3.5V
3.4V
3.3V
3.2V
3.1V
V
BAT
= 3V
I
CPO
= 200mA
V
BAT
= 3.3V
V
BAT
= 3V
V
CPO
= 4.2V
C2 = C3 = 2.2µF
C4 = 4.7µF
V
BAT
= 3.6V
V
BAT
= 3.9V
0
100
300
200
I
CPO
(mA)
400
500
3207 G06
3207fc
4
LTC3207/LTC3207-1
TYPICAL PERFORMANCE CHARACTERISTICS
2x Mode Charge Pump Open-Loop
Output Resistance vs Temperature
(2V
BAT
-V
CPO
) / I
CPO
5.0
OPEN LOOP OUTPUT RESISTANCE (Ω)
4.8
4.6
4.4
4.2
4.0
3.8
3.6
3.4
3.2
3.0
–40
–15
35
10
TEMPERATURE (°C)
60
85
3207 G07
T
A
= 25°C unless otherwise noted
Oscillator Frequency
vs V
BAT
Voltage
875
T
A
= –40°C
FREQUENCY (kHz)
2x Mode CPO Voltage vs I
CPO
5.2
5.1
5.0
CPO VOLTAGE (V)
4.9
4.8
4.7
4.6
4.5
4.4
4.3
4.2
0
C2 = C3 = 2.2µF
C4 = 4.7µF
100
300
200
I
CPO
(mA)
400
500
3207 G08
V
BAT
= 3V
V
CPO
= 4.8V
C2 = C3 = 2.2µF
C4 = 4.7µF
3.6V
3.5V
3.4V
3.3V
3.2V
3.1V
V
BAT
= 3V
850
825
T
A
= 85°C
T
A
= 25°C
800
775
2.9
3.3
4.5
4.1
4.9
3.7
V
BAT
VOLTAGE (V)
5.3
3207 G09
V
BAT
Shutdown Current
vs V
BAT
Voltage
7.5
V
BAT
SHUTDOWN CURRENT (µA)
6.5
T
A
= –40°C
V
BAT
CURRENT (µA)
5.5
T
A
= 85°C
4.5
3.5
2.5
1.5
2.9
T
A
= 25°C
500
495
490
485
480
475
470
465
460
455
3.3
4.5
4.1
4.9
3.7
V
BAT
VOLTAGE (V)
5.3
3207 G10
1x Mode No Load V
BAT
Current
vs V
BAT
Voltage
20
1.5x Mode V
BAT
Current vs I
CPO
(IV
BAT
-1.5I
CPO
)
V
BAT
= 3.6V
V
BAT
CURRENT (mA)
15
10
5
450
2.7 3.0 3.3 3.6 3.9 4.2 4.5 4.8 5.1 5.4
V
BAT
VOLTAGE (V)
3207 G11
0
0
100
300
200
I
CPO
(mA)
400
500
3207 G12
2x Mode V
BAT
Current vs I
CPO
(IV
BAT
- 2I
CPO
)
25
V
BAT
= 3.6V
450
400
CAM PIN CURRENT (mA)
CAM Pin Current
vs CAM Pin Voltage
V
BAT
= 3.6V
450
400
CAM LED CURRENT (mA)
350
300
250
200
150
100
50
0
0.2
0.6
0.8
0.4
CAM PIN VOLTAGE (V)
1.0
3207 G14
CAM LED Current
vs Input Code
20
V
BAT
CURRENT (mA)
350
300
250
200
150
100
50
15
10
5
0
0
100
200
300
400
I
CPO
(mA)
500
600
3207 G13
0
0.0
0 1 2 3 4 5 6 7 8 9 A B C D E F
INPUT CODE (HEX)
3207 G15
3207fc
5
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