CALMIRCO CM9156A

PRELIMINARY
CM9156A
Charge Pump White LED Driver
Features
Product Description
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The CM9156A is an efficient, 1.5x switched capacitor
(charge pump) regulator ideal for white LED applications. It has a regulated 4.5V, 120mA output, capable
of driving up to six parallel white LEDs. With a typical
operating input voltage range from 3.0V to 6.0V, the
CM9156A can be operated from a single-cell Li-Ion
battery.
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3.0V to 6.5V input voltage range
Dual mode operation: 1x and 1.5x
Fixed 4.5V output with initial accuracy of ± 2%
Supports up to 180mA (@4V) output
High efficiency at both high and low input voltages
Low external parts count, requires no inductor
PWM brightness control via the ENA pin
Selectable 8kHz, 32kHz, 262kHz, and 650kHz
switching frequency
Low shutdown current of <1µA
Soft start prevents excessive inrush current
Over-temperature and over-current protection
Low output ripple (<1%), low EMI
Input protection provides superior ESD rating
requiring only standard handling precautions
TDFN-10 or MSOP-10 package
Optional RoHS compliant lead free packaging
Applications
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Drives white LEDs to backlight color LCDs
Drives white or RGB LEDs for camera flash
Cellular phones
MP3 players
PDAs, GPS
It features an efficient, 1.5x charge pump circuit that
uses only two 1.0µF ceramic bucket capacitors and two
small capacitors for VIN and VOUT. The CM9156A
offers a selectable switching frequency of 8kHz, 32kHz,
262kHz, or 650kHz. The LED brightness can be
adjusted by applying a PWM signal on the ENA pin.
The CM9156A output voltage is regulated to 4.5V, ±
5% over the line and load ranges. Up 180mA of output
current is available. The proprietary design architecture
maintains high efficiency (> 80%), and at low VIN provides longer battery life. With a high VIN, or when the
adapter is powered, it provides cool reliable operation.
It offers low output voltage ripple, typically less than
50mV. Internal over-temperature and over-current
management provide short circuit protection.
The CM9156A is packaged in either a space saving
10-Lead TDFN or 10-Lead MSOP package. It can
operate over the industrial temperature range of -25°C
to 85°C.
Typical Application
4.5V
1.0uF
1.0uF
V OUT
C 1P
3.0V to 6.0V
V IN
1.0uF
C 2P
C 1N
PhotonICTM
CM9156A
1.0uF
30
30
30
GND
C L K1
C 2N
C L K2
E NA
© 2006 California Micro Devices Corp. All rights reserved.
04/26/06
490 N. McCarthy Blvd., Milpitas, CA 95035-5112
l
Tel: 408.263.3214
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Fax: 408.263.7846
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www.cmd.com
1
PRELIMINARY
CM9156A
Package Pinout
PACKAGE / PINOUT DIAGRAM
TOP VIEW
VOUT
1
10
C2P
C1P
2
9
C1N
VIN
3
8
GND
CLK1
4
7
C2N
CLK2
5
6
ENA
TOP VIEW
BOTTOM VIEW
(Pins Down View)
(Pins Up View)
10 9 8 7 6
1 2 3 4 5
CMxxx
xxxxxx
GND
PAD
Pin 1
Marking
10 9 8 7 6
1 2 3 4 5
CM9156A-01DE
10 Lead TDFN Package
CM9156A-01MR
10 Lead MSOP Package
Note: This drawing is not to scale.
Ordering Information
PART NUMBERING INFORMATION
Lead-free Finish
Pins
Package
Ordering Part Number1
10
TDFN
CM9156A-01DE
10
MSOP
CM9156A-01MR
Part Marking
Note 1: Parts are shipped in Tape & Reel form unless otherwise specified.
Specifications
ABSOLUTE MAXIMUM RATINGS
PARAMETER
RATING
UNITS
±2
kV
VIN to GND
[GND - 0.3] to +6.5
V
Pin Voltages
VOUT to GND
C1P, C1N to GND
C2P, C2N to GND
ENA, CLK1, CLK2 to GND
[GND - 0.3] to +6.0
[GND - 0.3] to +4.5
[GND - 0.3] to +4.5
[GND - 0.3] to +6.0
V
V
V
V
Storage Temperature Range
-65 to +150
°C
Operating Temperature Range
-40 to +85
°C
300
°C
ESD Protection (HBM)
Lead Temperature (Soldering, 10s)
© 2006 California Micro Devices Corp. All rights reserved.
2
490 N. McCarthy Blvd., Milpitas, CA 95035-5112
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Tel: 408.263.3214
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04/26/06
PRELIMINARY
CM9156A
Specifications (cont’d)
ELECTRICAL OPERATING CHARACTERISTICS
VIN = 3.6V. Typical values are at TA = 25 ºC
SYMBOL
VIN
ISD
IQ
PARAMETER
CONDITIONS
MIN
TYP
3.0
VIN Supply Voltage
Shut-Down Supply Current
Quiescent Current
MAX
6.0
1
UNIT
S
V
µA
ENA = 0
Fs = 8 kHz
250
380
µA
Fs = 32 kHz
280
470
µA
Fs = 262 kHz
800
1200
µA
Fs = 650 kHz
1600
2500
µA
4.2
4.5
4.7
V
4.0
4.1
4.2
V
Vin = 3.2V to 6.5V
4.4
4.5
4.6
V
Vin = 3.0V to 3.2V
Vout = 4.5V
4.0
4.1
4.3
120
V
mA
180
Charge Pump Circuit
Fs = 262 kHz or 650 kHz,
Iout = 0 mA to 120 mA,
VR LOAD
Load Regulation
Vin = 3.2V to 6.5V
Iout = 0 mA to 90 mA,
Vin = 3.0V to 3.2V
Fs = 262 kHz or 650 kHz,
VR LIN
IOUT
Iout = 60 mA,
Line Regulation
Output Current
VOUTR
Output Ripple Voltage
fs
Switching Frequency
Vout = 4.0V
Fs = 262 kHz, Iout = 60 mA
CLK1 = 0, CLK2 = 0
50
32.8
mA
mV
kHz
CLK1 = 1, CLK2 = 0
8.2
kHz
CLK1 = 0, CLK2 = 1
262
kHz
CLK1 = 1, CLK2 = 1
650
kHz
CLK1, CLK2
High Level Input Voltage
Low Level Input Voltage
1.2
VIH
High Level Input Voltage
1.3
VIL
Low Level Input Voltage
0.6
V
V
ENA
Protection
ILIM
V
0.4
V
600
mA
Over-current Limit
400
TJSD
Over-temperature Limit
135
ºC
THYS
Over-temperature Hysteresis
15
ºC
© 2006 California Micro Devices Corp. All rights reserved.
04/26/06
490 N. McCarthy Blvd., Milpitas, CA 95035-5112
l
Tel: 408.263.3214
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Fax: 408.263.7846
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www.cmd.com
3
PRELIMINARY
CM9156A
Typical Performance Curves
CIN=COUT=C1=C2=1.0μF, TA=25ºC, unless specified otherwise
Efficiency
Iout=120mA
Iout=60mA
100
100
90
Efficiency (%)
Efficiency (%)
Efficiency
80
70
60
90
80
70
60
50
3.0
3.5
4.0
4.5
5.0
5.5
50
3.0
6.0
3.5
Input Voltage (V)
5.0
5.5
6.0
650 kHz Load Regulation
4.75
4.75
5 Vin
5 Vin
4.50
Vout (V)
Vout (V)
4.5
Input Voltage (V)
262 kHz Load Regulation
4.25
3.6 Vin
3.4 Vin
4.00
4.50
3.6 Vin
3.4 Vin
4.25
4.00
10
30
50
70
90
110
10
Load Current (mA)
50
70
90
110
Line Regulation
Iout=120mA
4.6
4.5
4.5
4.4
4.4
Vout (V)
4.6
4.3
4.2
4.1
4.0
3.00
30
Load Current (mA)
Line Regulation
Iout=60mA
Vout (V)
4.0
4.3
4.2
4.1
4.00
5.00
6.00
4.0
3.00
4.00
Vin (V)
5.00
6.00
Vin (V)
© 2006 California Micro Devices Corp. All rights reserved.
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490 N. McCarthy Blvd., Milpitas, CA 95035-5112
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Tel: 408.263.3214
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04/26/06
PRELIMINARY
CM9156A
Typical Performance Curves (cont’d)
CIN=COUT=C1=C2=1.0μF, TA=25ºC, unless specified otherwise
Vout vs. Temperature
No Load Input Current
Vin = 3.6V
4.550
2000
650kHz
4.525
Vout (V)
Iq (ȝA)
1600
262kHz
1200
32kHz
800
4.475
8.2kHz
400
3.2
4.500
4.450
3.6
4.0
4.4
4.8
5.2
5.6
6.0
-40
-15
10
Vin (V)
Switching Frequency - 8kHz
85
Switching Frequency - 32kHz
34
8.3
Frequency (kHz)
Frequency (kHz)
60
Temperature (ºC)
8.5
85ºC
8.0
20ºC
7.8
- 40ºC
7.5
3.2
3.4
33
85ºC
32
20ºC
31
- 40ºC
3.6
3.8
4.0
4.2
4.4
30
3.2
4.6
3.4
Input Voltage (V)
3.6
3.8
4.0
4.2
4.4
4.6
Input Voltage (V)
Switching Frequency - 262kHz
Switching Frequency - 650kHz
278
690
Frequency (kHz)
Frequency (kHz)
35
270
85ºC
262
20ºC
254
670
85ºC
650
20ºC
630
- 40ºC
246
3.2
3.4
-40ºC
3.6
3.8
4.0
4.2
4.4
4.6
610
3.2
3.4
Input Voltage (V)
3.6
3.8
4.0
4.2
4.4
4.6
Input Voltage (V)
© 2006 California Micro Devices Corp. All rights reserved.
04/26/06
490 N. McCarthy Blvd., Milpitas, CA 95035-5112
l
Tel: 408.263.3214
l
Fax: 408.263.7846
l
www.cmd.com
5
PRELIMINARY
CM9156A
Typical Performance Curves (cont’d)
CIN=COUT=C1=C2=1.0μF, TA=25ºC, unless specified otherwise
Vin = 3.8V
Vin = 3.8V
Iout=120 mA
Iout=120 mA
Iout=60 mA
Iout=60 mA
100 mV/div
100 mV/div
Output Ripple, 262 kHz
Output Ripple, 650 kHz
Vin, 2V/div
Vout, 2V/div
Iin, 200 mA/div
Vin=3.8V
1 ms/div
Startup
Frequency Selection Table
Switching Frequency
8kHz
32kHz
262kHz
650kHz
CLK1
1
0
0
1
CLK2
0
0
1
1
Table 1: Frequency Selection
© 2006 California Micro Devices Corp. All rights reserved.
6
490 N. McCarthy Blvd., Milpitas, CA 95035-5112
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Tel: 408.263.3214
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Fax: 408.263.7846
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04/26/06
PRELIMINARY
CM9156A
Functional Block Diagram
3.0V T O 6.0V
1.0uF
1.0uF
V IN
C 1P
C 1N
L DOP
reR egulator
E NA
1.0uF
C 2P
C 2N
V OUT
1.5x C harge Pump
4.5V
1.0uF
OS C
C ounter
Driver
GND
CM9156A
C L K1
C L K2
Pin Discriptions
PIN DESCRIPTIONS
LEAD(s)
NAME
DESCRIPTION
1
VOUT
The regulated 4.5V output voltage pin. This pin requires a 1.0μF or larger ceramic
capacitor to ground. This pin connects to the anodes of the LEDs.
2
C1P
This pin is the plus side of charge pump bucket capacitor C1. Connect a 1.0μF
ceramic capacitor with a voltage rating of 10V or greater between C1N and C1P.
3
VIN
Positive supply voltage input pin. This voltage should be between 3.0V and 6V.
This pin requires a 1.0μF or larger ceramic capacitor to ground.
4
CLK1
Bit 1 for setting switching frequency (see Table 1)
5
CLK2
Bit 2 for setting switching frequency (see Table 1)
6
ENA
Enable pin, active high. By applying a PWM signal to this pin, the LED brightness
can be controlled.
7
C2N
This pin is the minus side of charge pump bucket capacitor C2. Connect a 1.0μF
ceramic capacitor between C2N and C2P.
8
GND
Ground pin.
9
C1N
This pin is the minus side of charge pump bucket capacitor C1. Connect a 1.0μF
ceramic capacitor between C1N and C1P.
10
C2P
This pin is the plus side of charge pump bucket capacitor C2. Connect a 1.0μF
ceramic capacitor between C2N and C2P.
© 2006 California Micro Devices Corp. All rights reserved.
04/26/06
490 N. McCarthy Blvd., Milpitas, CA 95035-5112
l
Tel: 408.263.3214
l
Fax: 408.263.7846
l
www.cmd.com
7
PRELIMINARY
CM9156A
Application Information
The CM9156A is a switched capacitor charge pump
voltage converter ideally suited for driving white LEDs
to backlight or sidelight LCD color displays for portable
devices such as cellular phones, PDAs and any application where small space and efficiency are critical.
The CM9156A charge pump is the perfect driver for
such portable applications, providing efficiency, compact overall size, low system cost and minimal EMI.
The CM9156A contains a linear low dropout (LDO)
regulator followed by a 1.5x fractional charge pump
that converts the nominal lithium-ion (Li-Ion) or lithium
polymer battery voltage levels (3.6V) by a gain of 1.5
times and regulates the converted voltage to 4.5V,
±-5%, enough to drive the forward voltage drop of white
LEDs. The CM9156A requires only two external
switched, or bucket, capacitors plus an input and an
output capacitor, providing for a compact, low profile
design. In many applications, all these can conveniently be the same value of 1.0μF, commonly available
in a compact 0805 surface mount package.
The CM9156A is intended for white LED applications,
but it can drive most all types of LEDs with a forward
voltage drop of less than 4V.
The LED current is determined by its series resistor,
RLED, and is approximately;
ILED =
4.5 V − VFWD _ LED
RLED
Typical white LEDs have a forward voltage drop,
VFWD_LED, of 3.5V to 3.7V. Like single junction devices,
white LEDs often have poorly matched forward voltages. If the LEDs were put in parallel without a series
resistor, the current in the paralleled branches would
vary, resulting in non-uniform brightness. RLED, in addition to setting the current, compensates for this variation by functioning as a ballast resistor, providing
negative feedback for each paralleled LED.
The input voltage, VIN, passes through an LDO preregulator that compares the output voltage to a
precision bandgap reference. After the LDO, the
charge pump boosts the LDO voltage by 1.5 times. A
feedback circuit to the LDO monitors the output
voltage, and when the output voltage reaches 4.5V, the
LDO output will operate at about 3V, regulating the
device output at 1.5 x 3V = 4.5V.
The charge pump uses two phases from the oscillator
to drive internal switches that are connected to the
bucket capacitors, C1 and C2, as shown in Figure 1. In
the first switch position, the bucket capacitors are connected in series and each are charged from the LDO to
a voltage of VLDO/2. The next phase changes the
switch positions so that C1 and C2 are put in parallel,
and places them on top of VLDO. The resulting voltage
across COUT is then; VLDO+1/2VLDO = 1.5 x VLDO.
When the input voltage rises above 5V, the charge
pump automatically disables, removing the voltage
gain stage and the output is then provided directly
through the LDO, regulated at 4.5V. This increases the
efficiency and minimizes chip heating in this operating
condition.
The CM9156A has over-temperature and over-current
protection circuitry to limit device stress and failure during short circuit conditions. An overcurrent condition
will limit the output current (approximately 400mA ~
600mA) and will cause the output voltage to drop, until
automatically resetting after removal of the excessive
current. Over-temperature protection disables the IC
when the junction is about 135°C, and automatically
turns on the IC when the junction temperature drops by
approximately 15°C.
CM9156A Operation
When a voltage exceeding the undervoltage lockout
threshold (UVLO) is applied to the VIN pin, the
CM9156A initiates a softstart cycle, typically lasting
1000μs. Softstart limits the inrush current while the output capacitors are charged during the power-up of the
device.
© 2006 California Micro Devices Corp. All rights reserved.
8
490 N. McCarthy Blvd., Milpitas, CA 95035-5112
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Tel: 408.263.3214
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Fax: 408.263.7846
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04/26/06
PRELIMINARY
CM9156A
Application Information (cont’d)
At nominal loads, the switching losses and quiescent
current are negligible. If these losses are ignored for
simplicity, the efficiency, η, for an ideal 1.5x charge
pump can be expressed as the output power divided by
the input power;
VOUT
C OUT
VIN
C1
FB
½ VLDO
P OUT
η ≈ ------------P IN
LDO
VLDO
For an ideal 1.5x charge pump, IIN = 1.5 x IOUT, and the
efficiency may be expressed as;
C2
½ VLDO
Charge C1 and C2 to ½ V
P OUT ⎛ V OUT × I OUT ⎞
V OUT
------------- ≈ ----------------------------------------- = --------------------P IN ⎝ V IN × 1.5 × I OUT⎠ 1.5 × V IN
LDO
VOUT
VIN
C1
FB
VOUT = 4.5V,
C OUT
½ VLDO
∴ η≈
4.5V
1.5 × VIN
The ideal 2x charge pump can be similarly expressed;
LDO
VLDO
P OUT
4.5V ------------- ≈ --------------------P IN
2.0 × V IN
C2
½ VLDO
In 1x mode, when the input voltage is above the output
voltage, the part functions as a linear regulator and the
ideal efficiency is simply VOUT/VIN.
The typical conversion efficiency plots for these modes,
with some losses, are shown in Figure 2.
Figure 1. Switch operation
Efficiency
Efficiency
Vout=4.5V
100
Efficiency (%)
A conventional charge pump with a fixed gain of 2x will
usually develop more voltage than is needed to drive
paralleled white LEDs from Li-Ion sources. This excessive gain develops a higher internal voltage, reducing
system efficiency and increasing battery drain in portable devices. A fractional charge pump with a gain of
1.5x is better suited for driving white LEDs in these
applications.
The CM9156A charge pump automatically switches
between two conversion gains, 1x and 1.5x, allowing
high efficiency levels over a wide operating input voltage range. The 1x mode allows the regulated LDO
voltage to pass directly through to the output when sufficient input voltage is available. The 1.5x charge pump
is enabled only when the battery input is too low to sustain the output load.
1X
85
70
CM9156A
dual mode
55
1.5X
2X
40
3.0
3.5
4.0
4.5
5.0
5.5
6.0
Input Voltage (V)
Figure 2. Ideal efficiency curve
© 2006 California Micro Devices Corp. All rights reserved.
04/26/06
490 N. McCarthy Blvd., Milpitas, CA 95035-5112
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Tel: 408.263.3214
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Fax: 408.263.7846
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www.cmd.com
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PRELIMINARY
CM9156A
Application Information (cont’d)
As can be seen, the CM9156A, with 1x and 1.5x
modes, has better efficiency in this application than a
fixed 2x charge pump. At low battery voltages, the
higher efficiency of the charge pump’s 1.5x gain
reduces the battery drain. At higher input voltages,
above 4.9V typically seen when the system is running
off an AC adapter, the CM9156A, operating the 1x
mode, has better efficiency than single mode 1.5x or
2x charge pumps, lowering the power dissipation for
cooler circuit operation and long life.
The external bucket capacitors will affect the output
impedance of the converter, so surface-mount, low
ESR ceramic capacitors are recommended. Tantalum
and Aluminum capacitors should not be used because
their ESR is too high. The ceramic dielectric must be
stable over the operating temperature and voltage
range hence X7R or X5R are recommended. In noise
sensitive applications, output ripple can be further
reduced by increasing the capacitance of the output
capacitor. Reflected input ripple current depends on
the impedance of the VIN source, which includes the
PCB traces. Increasing the input capacitor will reduce
this ripple. The input capacitor also affects the output
voltage ripple. All the capacitors should be located
close to the device for best performance.
LED Brightness Control
Changes in ambient light often require the backlight
display intensity to be adjusted, usually to conserve
battery life. There are simple solutions to lowering the
LED brightness when using the CM9156A. A typical
example is shown in Figure 3.
V in
C 1N
VIN
GND
C LK1
C 2N
C LK2
ENA
PWM input
Figure 3. PWM applied to ENA
VOUT
Frequency Selection
The frequency is typically selected to achieve maximum efficiency while avoiding sensitive frequencies
with the switching fundamental and its harmonics. The
switching frequency can be set outside the critical frequency spectrums of cellular communications bandwidths. Once set, the switching frequency and its
harmonics remain fixed, making filtering easy.
C 2P
C 1P
CM9156A
V in
The optimal switching frequency depends on the allowable system current draw, the load current, ripple and
EMI requirements. The CM9156A’s operating frequency choices are; 8kHz, 32kHz, 262kHz, or 650kHz.
These frequencies are selected by programming the
two digital inputs; CLK1 and CLK2. Refer to Table 1.
The supply current for a charge pump is proportional to
its switching frequency. A lower switching frequency
allows reduced quiescent current for more efficient
operation, but reduces the output current capability,
and in some cases, causes higher ripple. Higher frequencies are used when larger load currents are
demanded.
VOUT
C 2P
C 1P
C 1N
VIN
GND
C LK1
C 2N
C LK2
ENA
CM9156A
switc h
PWM input
Figure 4. Brightness control,
lower quiescent current
A PWM signal can be used to control the brightness,
which is more efficient than other solutions that dissipate unwanted LED current in the series resistors. It
also maintains LED color fidelity by avoiding color temperature changes that current variations cause to white
LEDs. The LED intensity is determined by the PWM
duty cycle, which can vary from 0% to 100%.
In the configuration shown in Figure 4, the brightness
is controlled by the PWM signal applied to the LEDs.
© 2006 California Micro Devices Corp. All rights reserved.
10 490 N. McCarthy Blvd., Milpitas, CA 95035-5112
l
Tel: 408.263.3214
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Fax: 408.263.7846
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04/26/06
PRELIMINARY
CM9156A
Application Information (cont’d)
Decreased Duty Cycle will lower the LED brightness,
See Figure 5 and Figure 6. The same signal is also
applied to the CM9156A, reducing the charge pump
switching frequency via the CLK2 control. When the
PWM signal is high, CLK1 is low, CLK2 goes high, the
operating frequency is 262kHz (refer to Table 1), and
the LED current path is complete through the switch.
When the PWM signal is low, the LED current is
stopped as the switch turns off, and the switching frequency of the charge pump becomes 32kHz (CLK1,
CLK2 = 0). Operating the charge pump at the lower frequency lowers the quiescent current when the charge
pump is operational (the input voltage below 5V).
The recommended PWM frequency is between 100Hz
and 20kHz. If a frequency of less then 100Hz is used,
flicker might be seen in the LEDs. The frequency
should also be greater than the refresh rate of the TFT
display. Higher frequencies will cause a loss of brightness control linearity. In addition, higher frequency can
cause chromaticity shifts because the fixed rise and fall
times of the PWM signal will shift the forward current.
C2N, 5V/div
PWM, 20 kHz,
10% D.C., 5V/div
Vout ripple,
200 mV/div
Iin, 200 mA/div
Vin=3.8V
20 uSec/div
Figure 6. Low brightness waveforms
Camera Flash Application
Many smart phones and PDAs include a digital camera. These cameras typically utilize a WLED flash to
illuminate the picture subject in low light conditions.
The CM9156A is easily adapted to such an application.
Figure 7 is a typical application using the CM9156A as
a WLED flash driver, which is ideal for this application
because it is capable of driving up to 120mA from a Liion battery. The One-shot is used to create a single
pulse of a set duration to the ENA pin of the CM9156A.
C2N, 5V/div
PWM, 20 kHz,
60% D.C., 5V/div
Vout ripple,
200 mV/div
Iin, 200 mA/div
The Flash LED modules shown here contain three
matched WLEDs with a common anode and separated
cathodes. The series resistor is chosen based on the
forward drop of the module LEDs (typically 3.3V to
3.8V) and the number of parallel LEDs being driven.
Vin=3.8V
20 uSec/div
Figure 5. High brightness waveforms
© 2006 California Micro Devices Corp. All rights reserved.
04/26/06
490 N. McCarthy Blvd., Milpitas, CA 95035-5112
l
Tel: 408.263.3214
l
Fax: 408.263.7846
l
www.cmd.com
11
PRELIMINARY
CM9156A
Application Information (cont’d)
V in
VOUT
C 2P
C 1P
C 1N
VIN
GND
C LK1
C 2N
C LK2
ENA
R CAT HODE
R CAT HODE
CM9156A
Flash
One- shot
Pulse
t
Figure 7. Camera flash application
Layout Guide
The charge pump is rapidly charging and discharging
its external capacitors, so external traces to the capacitors should be made as wide and short as allowable to
minimize inductance and high frequency ringing. The
four capacitors should be located as close as practical
to the charge pump, particularly C1 and C2, which
have the highest dv/dt. Connect ground and power
traces to the capacitors through short, low impedance
paths. Use a solid ground plane, ideally on the backside of the PCB, which should carry only ground potential. Connect the ground side of CIN, Cout and the chip
GND as close as practical. For best thermal performance, the exposed backside lead frame should be
soldered to the PCB.
© 2006 California Micro Devices Corp. All rights reserved.
12 490 N. McCarthy Blvd., Milpitas, CA 95035-5112
l
Tel: 408.263.3214
l
Fax: 408.263.7846
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www.cmd.com
04/26/06
PRELIMINARY
CM9156A
Application Evaluation Circuit
Note 1:
Note 2:
Note 3:
Note 4:
Note 5:
Note 6:
Pull-up and current setting resistor values will vary with application.
JP1 jumper selects either Flash WLED application or WLED for LCD backlight application.
JP2 jumper selects Flash signal or disables signal connected to ENA pin If JP2 is not jumpered, then ENA is pulled high.
Flash WLEDs have three cathodes and one common anode.
The SN74LS02 is configured as a one-shot pulse generator, with time controlled by R12, R16, and C5.
J3 jumper inserted will create a 1/60 s flash pulse (16 ms). Without J3 jumper inserted the flash pulse will be will 1/30 s (33
ms.
© 2006 California Micro Devices Corp. All rights reserved.
04/26/06
490 N. McCarthy Blvd., Milpitas, CA 95035-5112
l
Tel: 408.263.3214
l
Fax: 408.263.7846
l
www.cmd.com
13
PRELIMINARY
CM9156A
Mechanical Details
TDFN-10 Mechanical Specifications
Mechanical Package Diagrams
Dimensions for the CM9156A packaged in a 10-lead
TDFN package are presented below.
For complete information on the TDFN-10, see the California Micro Devices TDFN Package Information document.
D
10 9 8 7 6
PACKAGE DIMENSIONS
TDFN
JEDEC
No.
MO-229 (Var. WEED-3)=
Leads
10
Millimeters
Pin 1
Marking
Inches
Min
Nom
Max
Min
Nom
Max
A
0.70
0.75
0.80
0.028
0.030
0.031
A1
0.00
0.02
0.05
0.000
0.001
0.002
A2
0.45
0.55
0.65
0.018
0.022
0.026
A3
0.20
b
0.18
D
0.25
0.008
0.30
0.007
3.00
D2
2.20
E
2.30
2.40
0.087
E2
1.40
e
1.50
TOP VIEW
0.10 C
0.010
0.012
0.118
3.00
1 2 3 4 5
0.08 C
0.091
0.094
A1
0.118
1.60
0.055
0.50
0.060
A
SIDE VIEW
A3 A2
0.063
0.020
K
1.30
1.50
1.70
0.051
0.060
0.067
L
0.20
0.30
0.40
0.008
0.012
0.016
# per
tube
NA
# per
tape and
reel
3000 pieces
1
2
3
4
5
Pin 1 ID
C0.35
E2
Dim.
E
Package
GND PAD
L
D2
Controlling dimension: millimeters
=This package is compliant with JEDEC standard MO-229, variation
WEED-3 with exception of the "D2" and "E2" dimensions as called
out in the table above.
10
K
9
8
7
6
b
e
8X
BOTTOM VIEW
0.10
M
CAB
Package Dimensions for 10-Lead TDFN
© 2006 California Micro Devices Corp. All rights reserved.
04/26/06
490 N. McCarthy Blvd., Milpitas, CA 95035-5112
l
Tel: 408.263.3214
l
Fax: 408.263.7846
l
www.cmd.com
14
PRELIMINARY
CM9156A
Mechanical Details (cont’d)
MSOP-10 Mechanical Specifications:
Mechanical Package Diagrams
The CM9156A is supplied in a 10-pin MSOP. Dimensions are presented below.
TOP VIEW
For complete information on the MSOP-10, see the
California Micro Devices MSOP Package Information
document.
D
10
9
8
6
7
PACKAGE DIMENSIONS
Package
MSOP
Pins
10
Dimensions
Pin 1
Marking
Millimeters
Inches
Min
Max
Min
Max
A
0.75
0.95
0.030
0.038
A1
0.05
0.15
0.002
0.006
B
0.17
0.33
0.007
0.013
C
0.15
0.30
0.006
0.018
D
2.90
3.10
0.114
0.122
E
2.90
3.10
0.114
0.122
e
0.50 BSC
0.0197 BSC
H
4.90 BSC
0.193 BSC
L
# per tape
and reel
0.40
E
H
0.70
0.0157
1
2
3
5
4
SIDE VIEW
A
SEATING
PLANE
A1
B
e
0.0276
END VIEW
4000
C
Controlling dimension: inches
L
Package Dimensions for MSOP-10
© 2006 California Micro Devices Corp. All rights reserved.
04/26/06
490 N. McCarthy Blvd., Milpitas, CA 95035-5112
l
Tel: 408.263.3214
l
Fax: 408.263.7846
l
www.cmd.com
15