LTC3201 [Linear]
100mA Ultralow Noise Charge Pump LED Supply with Output Current Adjust; 百毫安超低噪声充电泵LED ，电源输出电流调整
| 型号： | LTC3201 |
| 厂家： | 
Linear |
| 描述： | 100mA Ultralow Noise Charge Pump LED Supply with Output Current Adjust |
| 文件： | 总8页 (文件大小：92K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
LTC3201
100mA Ultralow Noise
Charge Pump LED Supply
with Output Current Adjust
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FEATURES
DESCRIPTIO
The LTC®3201 is an ultralow noise, constant frequency,
charge pump DC/DC converter specifically designed for
powering white LEDs. The part produces a low noise
boosted supply capable of supplying 100mA of output
current. LED current is regulated for accurate and stable
backlighting. A 3-bit DAC provides output current adjust
for brightness control.
■
Input Noise Filter Minimizes Supply Noise
■
Constant Frequency Operation
■
3-Bit LED Current Control
No Inductors
Low Shutdown Current: IIN < 1µA
Output Current: 100mA
VIN Range: 2.7V to 4.5V
1.8MHz Switching Frequency
■
■
■
■
■
Low external parts count (one small flying capacitor and
three small bypass capacitors) and small MSOP-10 pack-
age size make the LTC3201 ideally suited for space con-
strained applications. An input noise filter further reduces
inputnoise,thus enablingdirectconnectiontothebattery.
Highswitchingfrequencyenablestheuseofsmallexternal
capacitors.
■
Soft-Start Limits Inrush Current at Turn-On
■
Short-Circuit and Overtemperature Protected
■
Available in 10-Pin MSOP Package
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APPLICATIO S
■
White LED Backlighting
Programmable Boost Current Source
The LTC3201 contains overtemperature protection and
can survive an indefinite output short to GND. Internal
soft-start circuitry also prevents excessive inrush current
on start-up. A low current shutdown feature disconnects
the load from VIN and reduces quiescent current to less
than 1µA.
■
, LTC and LT are registered trademarks of Linear Technology Corporation.
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TYPICAL APPLICATIO
Ultralow Noise White LED Driver
with Adjustable Current Control
Input Current Ripple
I
I
= 100mA
= 205mA
= 3.6V
OUT
0.22µF
IN
V
IN
CM
CP
UP TO
6-WHITE LEDs
V
IN
+
50mA/DIV
1µF
Li ION
V
OUT
FILTER
1µF
0.22µF
LTC3201
• • •
LED
CURRENT
ADJUST
3
D0-D2
GND
FB
56Ω
56Ω
56Ω
3201 TA01b
100ns/DIV
3201 TA01a
3201f
1
LTC3201
W W U W
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ABSOLUTE AXI U RATI GS
PACKAGE/ORDER I FOR ATIO
(Note 1)
ORDER PART
TOP VIEW
VIN, VFILTER, VOUT, CP, CM to GND .............. –0.3V to 6V
D0, D1, D2, FB to GND ................. –0.3V to (VIN + 0.3V)
VOUT Short-Circuit Duration............................. Indefinite
IOUT ...................................................................................... 150mA
Operating Temperature Range (Note 2) ...–40°C to 85°C
Storage Temperature Range ................. –65°C to 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C
NUMBER
V
1
2
3
4
5
10 FB
OUT
CP
9
8
7
6
V
IN
FILTER
CM
GND
D2
D1
D0
LTC3201EMS
MS PACKAGE
10-LEAD PLASTIC MSOP
MS PART
MARKING
TJMAX = 150°C
θJA = 130°C/W (1 LAYER BOARD)
θJA = 100°C/W (4 LAYER BOARD)
LTVB
Consult LTC Marketing for parts specified with wider operating temperature ranges.
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. VIN = 3.6V, CFILTER = CFLY = 0.22µF, CIN = COUT = 1µF,
tMIN to tMAX unless otherwise noted.
PARAMETER
CONDITIONS
MIN
TYP
MAX
4.5
6.5
1
UNITS
V
V
V
V
Operating Voltage
Operating Current
Shutdown Current
●
●
●
2.7
IN
IN
IN
I
= 0mA
4
mA
µA
OUT
D0, D1, D2 = 0V, V
= 0V
OUT
Open-Loop Output Impedance
Input Current Ripple
Output Ripple
I
I
I
= 100mA
8
30
Ω
OUT
= 200mA
mA
mV
IN
P-P
= 100mA, C
= 1µF
30
OUT
OUT
P-P
V
V
Regulation Voltage
DAC Step Size
D0 = D1 = D2 = V
●
0.57
0.63
90
0.66
V
FB
FB
IN
mV
MHz
V
Switching Frequency
Oscillator Free Running
1.4
0.4
–1
1.8
D0 to D2 Input Threshold
D0 to D2 Input Current
●
●
1.1
1
µA
V
V
Short-Circuit Current
Turn-On Time
V
= 0V
150
1
mA
ms
OUT
OUT
OUT
I
= 0mA
OUT
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: The LTC3201E is guaranteed to meet performance specifications
from 0°C to 70°C. Specifications over the –40°C to 85°C operating
temperature range are assured by design, characterization and correlation
with statistical process controls.
3201f
2
LTC3201
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TYPICAL PERFOR A CE CHARACTERISTICS
Feedback Voltage vs Supply
Voltage
Oscillator Frequency vs Supply
Voltage
Output Voltage vs Load Current
4.15
4.10
4.05
4.00
3.95
3.90
3.85
3.80
2.2
2.0
1.8
1.6
1.4
1.2
0.640
0.635
0.630
0.625
0.620
0.615
0.610
0.605
C
C
T
= C
OUT
= 25°C
= O.22µF
C
C
V
= C
OUT
= 4V
= O.22µF
FLY
IN
A
FILTER
C
C
= C
OUT
= O.22µF
FLY
IN
OUT
FILTER
FLY
IN
FILTER
= C
= 1µF
= C = 1µF
= C
= 1µF
T
A
= 85°C
T = –40°C
A
V
= 4.5V
IN
T
= 25°C
A
T
= 25°C
A
T
= 85°C
A
T
A
= –40°C
V
= 3.2V
IN
V
= 2.7V
IN
20 40 60 80 100 120 140 160 180 200
0
2.7
3.3
3.6
3.9
4.2
4.5
3.0
3.9
4.5
2.7
3.0
3.3
3.6
4.2
LOAD CURRENT (mA)
SUPPLY VOLTAGE (V)
SUPPLY VOLTAGE (V)
3201 G02
3201 G03
3201 G01
Feedback Voltage
Short-Circuit Current vs Supply
Voltage
vs Supply Voltage
IOUT = 100mA, VOUT = 4V
Feedback Voltage vs IOUT
0.64
0.62
0.60
0.58
0.56
0.54
0.52
0.50
250
200
150
100
50
0.620
0.615
0.610
0.605
0.600
0.595
0.590
C
C
T
= C
= O.22µF
FILTER
C
C
T
= C
OUT
= 25°C
= O.22µF
C
C
T
= C
= 0.22µF
FLY
IN
A
FLY
IN
A
FILTER
= 1µF
FLY
IN
A
FILTER
= C
= 1µF
OUT
= C
= C
= 1µF
OUT
= 25°C
= 25°C
V
= 3.6V
IN
0
0
20 40 60 80 100 120 140 160180 200 220
(mA)
3.9
4.2
2.7
3.3
3.6
3.9
4.2
2.7
3.3
3.6
4.5
4.5
3.0
3.0
I
SUPPLY VOLTAGE (V)
SUPPLY VOLTAGE (V)
OUT
3201 G06
3201 G04
3201 G05
3201f
3
LTC3201
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PI FU CTIO S
VOUT (Pin 1): Charge Pump Output. Bypass with a 1µF
internal reference voltage. The DAC output reference volt-
age is used to regulate amount of current flowing through
the LEDs. An internal control loop adjusts the charge
pumpoutputsuchthatthevoltagedropacrossanexternal
sense resistor connected from FB to GND equals the
internal DAC output reference voltage. See Truth Table in
Applications Information section for internal reference
settings vs DAC code. When D0 to D2 are low, the part
enters a low current shutdown mode and the load is
disconnected from VIN.
ceramic capacitor to GND.
CP (Pin 2): Flying Capacitor Positive Terminal.
FILTER (Pin 3): Input Noise Filter Terminal. Bypass with a
0.22µF high resonant frequency ceramic capacitor to
GND. Place filter capacitor less than 1/8" from device.
CM (Pin 4): Flying Capacitor Negative Terminal.
GND (Pin 5): Ground. Connect to a ground plane for best
performance.
VIN (Pin 9): Input Voltage. VIN may be between 2.7V and
4.5V. Bypass VIN with a 1µF low ESR capacitor to ground.
D0 (Pin 6): Current Control DAC LSB Input.
D1 (Pin 7): Current Control DAC Bit 1 Input.
FB (Pin 10): Charge Pump Feedback Input. This pin acts
as a sense pin for IOUT. Connect a sense resistor between
FBandGNDtosettheoutputcurrent. IOUT willbe adjusted
until VFB = internal DAC output reference.
D2 (Pin 8): Current Control DAC MSB Input. Inputs D0 to
D2 program a 3-bit DAC output which is used as the
W
W
SI PLIFIED BLOCK DIAGRA
SOFT-START
AND
SWITCH CONTROL
1
V
OUT
FB 10
1.8MHz
OSCILLATOR
–
+
CHARGE
PUMP
2
4
CP
CM
3
9
FILTER
LPF
V
IN
1.2V
8
7
6
D2
D1
D0
3-BIT
DAC
5
3201 BD
GND
3201f
4
LTC3201
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APPLICATIO S I FOR ATIO
can go down to zero during this time. At the full load of
100mA at the output, this means that the input could
potentially go from 200mA down to 0mA during the
nonoverlap time. The LTC3201 mitigates this problem by
minimizing the nonoverlap time, using a high (1.8MHz)
frequency clock, and employing a novel noise FILTER
network. The noise filter consists of internal circuitry plus
external capacitors at the FILTER and VIN pins. The filter
capacitor serves to cancel the higher frequency compo-
nents of the noise, while the VIN capacitor cancels out the
lower frequency components. The recommended values
are 0.22µF for the FILTER capacitor and 1µF for the VIN
capacitor.Notethatthesecapacitorsmustbeofthehighest
possibleresonantfrequencies.SeeLayoutConsiderations.
Operation (Refer to Simplified Block Diagram)
The LTC3201 is a switched capacitor boost charge pump
especially designed to drive white LEDs in backlighting
applications. The LTC3201’s internal regulation loop
maintains constant LED output current by monitoring the
voltage at the FB pin. The device has a novel internal filter
that, along with an external 0.22µF capacitor, significantly
reduces input current ripple. An internal 7-state DAC
allows the user to lower the regulation voltage at the FB
pin, thus lowering the LED current. To regulate the output
current, the user places a sense resistor between FB and
GND. The white LED is then placed between VOUT and FB.
The value at the FB pin is then compared to the output of
the DAC. The charge pump output voltage is then changed
to equalize the DAC output and the FB pin. The value of the
sense resistor determines the maximum value of the
output current.
3-Bit DAC for Output Current Control
Digital pins D0, D1, D2 are used to control the output
currentlevel.D0=D1=D2=VIN allowstheusertoprogram
When the charge pump is enabled, a two-phase
nonoverlappingclockactivatesthechargepumpswitches.
The flying capacitor is charged to VIN on phase one of the
clock. Onphasetwooftheclock, itisstackedinserieswith
VIN andconnectedtoVOUT. Thissequenceofchargingand
discharging the flying capacitor continues at a free run-
ning frequency of 1.8MHz (typ) until the FB pin voltage
reaches the value of the DAC.
anoutputLEDcurrentthatisequalto0.63V/R
SENSE
, where
SENSE
R
is the resistor connected to any single LED and
connected between FB and ground. Due to the finite
transconductance of the regulation loop, for a given diode
setting, the voltage at the FB Pin will decrease as output
current increases. All LEDs subsequently connected in
parallel should then have similar currents. The mismatch-
ing of the LED VF and the mismatching of the sense
resistors will cause a differential current error between
LEDs connected to the same output. Once the sense
resistor is selected, the user can then control the voltage
applied across that resistor by changing the digital values
at D0:D2. This in turn controls the current into the LED.
Note that there are only 7 available current states. The 8th
is reserved to shutdown. This is the all 0s code. Refer to
Table below.
In shutdown mode all circuitry is turned off and the
LTC3201 draws only leakage current (<1µA) from the VIN
supply. Furthermore, VOUT is disconnected from VIN. The
LTC3201 is in shutdown when a logic low is applied to all
three D0:D2 pins. Note that if VOUT floats to >1.5V,
shutdown current will increase to 10µA max. In normal
operation, the quiescent supply current of the LTC3201
willbeslightlyhigherifanyoftheD0:D2pinsisdrivenhigh
with a signal that is below VIN than if it is driven all the way
to VIN. Since the D0:D2 pins are high impedance CMOS
inputs, they should never be allowed to float.
D0
D1
D2
FB
0.63V
0.54V
0.45V
0.36V
0.27V
0.18V
0.09V
Shutdown
HIGH
HIGH
HIGH
HIGH
LOW
LOW
LOW
LOW
HIGH
HIGH
LOW
LOW
HIGH
HIGH
LOW
LOW
HIGH
LOW
HIGH
LOW
HIGH
LOW
HIGH
LOW
Input Current Ripple
The LTC3201 is designed to minimize the current ripple at
VIN. Typical charge pump boost converters draw large
amounts of current from VIN during both phase 1 and
phase 2 of the clocking. If there is a large nonoverlap time
betweenthetwophases, thecurrentbeingdrawnfromVIN
3201f
5
LTC3201
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APPLICATIO S I FOR ATIO
Power Efficiency
VIN, VFILTER Capacitor Selection
The power efficiency (η) of the LTC3201 is similar to that
of a linear regulator with an effective input voltage of twice
the actual input voltage. This occurs because the input
current for a voltage doubling charge pump is approxi-
mately twice the output current. In an ideal regulator the
power efficiency would be given by:
The value and resonant frequency of CFILTER and CIN
greatly determine the current noise profile at VIN. CFILTER
should be a high frequency 0.22µF capacitor with a reso-
nant frequency over 30MHz. Input capacitor CIN should be
a 1µF ceramic capacitor with a resonant frequency over
1MHz. The X5R capacitor is a good choice for both. The
values of CFILTER (0.22µF) and CIN (1µF) provide optimum
high and low frequency input current filtering. A higher
filter cap value will result in lower low frequency input
current ripple, but with increased high frequency ripple.
The key at the FILTER node is that the capacitor has to be
very high frequency. If capacitor technology improves the
bandwidth, then higher values should be used. Similarly,
increasing the input capacitor value but decreasing its
resonant frequency will not really help. Decreasing it will
help the high frequency performance while increasing the
low frequency current ripple.
POUT VOUT •IOUT VOUT
η =
=
=
P
V •2IOUT
IN
2V
IN
IN
At moderate to high output power the switching losses
and quiescent current of LTC3201 are relatively low. Due
to the high clocking frequency, however, the current used
forcharginganddischargingtheswitchesstartstoreduce
efficiency. Furthermore, due to the low VF of the LEDs,
power delivered will remain low.
Short-Circuit/Thermal Protection
The LTC3201 has short-circuit current limiting as well as
overtemperature protection. During short-circuit condi-
tions, the output current is limited to typically 150mA.
On-chip thermal shutdown circuitry disables the charge
pump once the junction temperature exceeds approxi-
mately 160°C and re-enables the charge pump once the
junction temperature drops back to approximately 150°C.
The LTC3201 will cycle in and out of thermal shutdown
indefinitely without latchup or damage until the short-
circuit on VOUT is removed.
Direct Connection to Battery
Due to the ultra low input current ripple, it is possible to
connect the LTC3201 directly to the battery without using
regulators or high frequency chokes.
Flying Capacitor Selection
Warning: A polarized capacitor such as tantalum or alumi-
num should never be used for the flying capacitor since its
voltage can reverse upon start-up. Low ESR ceramic
capacitors should always be used for the flying capacitor.
The flying capacitor controls the strength of the charge
pump. In order to achieve the rated output current it is
necessary to have at least 0.22µF of capacitance for the
flying capacitor. Capacitors of different materials lose
their capacitance with higher temperature and voltage at
different rates. For example, a ceramic capacitor made of
X7R material will retain most of its capacitance from
–40°C to 85°C whereas a Z5U and Y5V style capacitor will
lose considerable capacitance over that range. Z5U and
Y5V capacitors may also have a very strong voltage
coefficient causing them to lose 60% or more of their
capacitance when the rated voltage is applied. Therefore,
when comparing different capacitors it is often more
VOUT Capacitor Selection
The style and value of capacitors used with the LTC3201
determine several important parameters such as output
ripple, charge pump strength and minimum start-up time.
To reduce noise and ripple, it is recommended that low
ESR (<0.1Ω) capacitors be used for CFILTER, CIN, COUT
.
These capacitors should be ceramic.
The value of COUT controls the amount of output ripple.
Increasing the size of COUT to 10µF or greater will reduce
the output ripple at the expense of higher turn-on times
and start-up current. See the section Output Ripple. A 1µF
COUT is recommended.
3201f
6
LTC3201
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APPLICATIO S I FOR ATIO
F is the switching frequency (1.8MHz typ).
appropriate to compare the achievable capacitance for a
given case size rather than discussing the specified ca-
pacitance value. For example, over the rated voltage and
temperature,a1µF,10V,Y5Vceramiccapacitorinan0603
case may not provide any more capacitance than a 0.22µF
10V X7R available in the same 0603 case. The capacitor
manufacturer’s data sheet should be consulted to deter-
mine what value of capacitor is needed to ensure 0.22µF
at all temperatures and voltages.
Loop Stability
Both the style and the value of COUT can affect the stability
of the LTC3201. The device uses a closed loop to adjust
the strength of the charge pump to match the required
output current. The error signal of this loop is directly
stored on the output capacitor. The output capacitor also
serves to form the dominant pole of the loop. To prevent
ringing or instability, it is important for the output capaci-
tor to maintain at least 0.47µF over all ambient and
operating conditions.
Below is a list of ceramic capacitor manufacturers and
how to contact them:
AVX
(843) 448-9411
(864) 963-6300
(770) 436-1300
(800) 348-2496
(610) 644-1300
www.avxcorp.com
www.kemet.com
www.murata.com
www.t-yuden.com
www.vishay.com
Excessive ESR on the output capacitor will degrade the
loop stability of the LTC3201. The closed loop DC imped-
ance is nominally 0.5Ω. The output will thus change by
50mV with a 100mA load. Output capacitors with ESR of
0.3Ω or greater could cause instability or poor transient
response. To avoid these problems, ceramic capacitors
should be used. A tight board layout with good ground
plane is also recommended.
Kemet
Murata
Taiyo Yuden
Vishay
Open-Loop Output Impedance
The theoretical minimum open-loop output impedance of
a voltage doubling charge pump is given by:
Soft-Start
The LTC3201 has built-in soft-start circuitry to prevent
excessive input current flow at VIN during start-up. The
soft-start time is programmed at approximately 30µs.
2V – VOUT
1
FC
IN
ROUT(MIN)
=
=
IOUT
where F if the switching frequency (1.8MHz typ) and C is
the value of the flying capacitor. (Using units of MHz and
µF is convenient since they cancel each other). Note that
the charge pump will typically be weaker than the theoreti-
cal limit due to additional switch resistance. Under normal
operation, however, with VOUT ≈ 4V, IOUT < 100mA,
VIN >3V, theoutputimpedanceisgivenbytheclosed-loop
value of ~0.5Ω.
Layout Considerations
Due to the high switching frequency and large transient
currentsproducedbytheLTC3201, carefulboardlayoutis
necessary. A true ground plane is a must. To minimize
highfrequencyinputnoiseripple,itisespeciallyimportant
that the filter capacitor be placed with the shortest dis-
tancetotheLTC3201(1/8inchorless).Thefiltercapacitor
should have the highest possible resonant frequency.
Conversely, the input capacitor does not need to be placed
close to the pin. The input capacitor serves to cancel out
the lower frequency input noise ripple. Extra inductance
ontheVIN lineactuallyhelpsinputcurrentripple. Notethat
if the VIN trace is lengthened to add parasitic inductance,
it starts to look like an antenna and worsen the radiated
noise. Itisrecommendedthatthefiltercapacitorbeplaced
on the left hand side next to Pin 3. The flying capacitor can
then be placed on the top of the device. It is also important
3201f
Output Ripple
ThevalueofCOUT directlycontrolstheamountofripplefor
agivenloadcurrent.IncreasingthesizeofCOUT willreduce
the output ripple at the expense of higher minimum turn-
on time and higher start-up current. The peak-to-peak
output ripple is approximated by the expression:
IOUT
2F •COUT
VRIPPLE(P−P)
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen-
tationthattheinterconnectionofitscircuitsasdescribedhereinwillnotinfringeonexistingpatentrights.
7
LTC3201
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TYPICAL APPLICATIO
toplacetheoutputcapacitorasclosetothepinaspossible
to minimize inductive ringing and parasitic resistance.
automatically deactivate the output. To reduce the maxi-
mum junction temperature, a good thermal connection to
PC board is recommended. Connecting the GND pin (Pin
4) to a ground plane, and maintaining a solid ground plane
under the device on two layers of the PC board can reduce
the thermal resistance of the package and PC board
system.
Thermal Management
For higher input voltages and maximum output current
there can be substantial power dissipation in the
LTC3201. If the junction temperature increases above
approximately160°C the thermal shutdown circuitry will
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PACKAGE DESCRIPTIO
MS Package
10-Lead Plastic MSOP
(Reference LTC DWG # 05-08-1661)
3.00 ± 0.102
(.118 ± .004)
(NOTE 3)
0.889 ± 0.127
(.035 ± .005)
0.497 ± 0.076
(.0196 ± .003)
REF
10 9
8
7 6
5.23
(.206)
MIN
3.2 – 3.45
(.126 – .136)
3.00 ± 0.102
(.118 ± .004)
NOTE 4
4.88 ± 0.10
(.192 ± .004)
DETAIL “A”
0.254
(.010)
0° – 6° TYP
GAUGE PLANE
0.50
(.0197)
BSC
3.05 ± 0.38
(.0120 ± .0015)
1 2
3
4 5
TYP
0.53 ± 0.01
(.021 ± .006)
RECOMMENDED SOLDER PAD LAYOUT
WITHOUT EXPOSED PAD OPTION
0.86
(.034)
REF
1.10
(.043)
MAX
DETAIL “A”
0.18
(.007)
SEATING
PLANE
NOTE:
0.17 – 0.27
(.007 – .011)
0.13 ± 0.05
(.005 ± .002)
MSOP (MS) 1001
1. DIMENSIONS IN MILLIMETER/(INCH)
2. DRAWING NOT TO SCALE
0.50
(.0197)
TYP
3. DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS.
MOLD FLASH, PROTRUSIONS OR GATE BURRS SHALL NOT EXCEED 0.152mm (.006") PER SIDE
4. DIMENSION DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS.
INTERLEAD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.152mm (.006") PER SIDE
5. LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING) SHALL BE 0.102mm (.004") MAX
RELATED PARTS
PART NUMBER
LTC1682/-3.3/-5
LTC1751/-3.3/-5
LTC1754-3.3/-5
LTC1928-5
DESCRIPTION
COMMENTS
MS8 and SO-8 Packages, I
Doubler Charge Pumps with Low Noise LDO
Doubler Charge Pumps
= 80mA, Output Noise = 60µV
RMS
OUT
V
= 5V at 100mA, V
= 3.3V at 80mA, ADJ, MSOP Packages
OUT
OUT
Doubler Charge Pumps with Shutdown
Doubler Charge Pumps with Low Noise LDO
Low Noise Boost Regulator LED Driver
Low Noise Doubler Charge Pump
ThinSOTTM Package, I = 13µA, I
= 50mA
OUT
Q
ThinSOT Output Noise = 90µV
, V
= 5V, V = 2.7V to 4.4V
RMS OUT IN
LT1932
ThinSOT Package, High Efficiency, up to 16 LEDs
LTC3200/-5
MS8 and ThinSOT (LTC3200-5) Package, I
2MHz Fixed Frequency
= 100mA,
OUT
LTC3202
Low Noise High Efficiency Charge Pump
MS10 Package, 125mA Output, High Efficiency
ThinSOT is a trademark of Linear Technology Corporation.
3201f
LT/TP 0102 2K • PRINTED IN USA
LinearTechnology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
8
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LINEAR TECHNOLOGY CORPORATION 2001
(408) 432-1900 FAX: (408) 434-0507 www.linear.com
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