CALMIRCO CM9153-01DE

PRELIMINARY
CM9153
Charge Pump White LED Driver
Features
Product Description
•
•
•
•
•
•
•
•
•
•
•
•
•
The CM9153 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
CM9153 can be operated from a single cell Li-Ion battery.
•
•
3.0V to 6.5V input voltage range
Two mode operation; 1x and 1.5x
Fixed 4.5V output with initial accuracy of ± 2%
Supports 150mA (@4V) continuous output current
High efficiency at both high and low input voltages
Low external parts count, requires no inductor
PWM brightness control via the ENA pin
650-kHz 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-8 or MSOP-8 package
Optional RoHS compliant lead free packageing
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 LED
brightness can be adjusted by applying a PWM signal
on the ENA pin.
The CM9153 output voltage is regulated to 4.5V, ± 5%
over the line and load ranges. Up 150mA of output current is available. A proprietary design architecture
(patent pending) maintains high efficiency (> 80%), at
both below 3.2 VIN, resulting in longer battery life, and
above 5.25 VIN, when an adapter is plugged in, keeping the part cool. It offers low output voltage ripple, typically less than 50mV. Internal over-temperature and
over-current management provide short circuit protection.
Applications
•
•
•
•
•
Drive white LEDs to backlight color LCDs
Drive white or RGB LEDs for camera flash
Cellular phones
MP3 players
PDAs, GPS
The CM9153 is packaged in either a space-saving 8lead TDFN or 8-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
C 2P
C 1N
V OUT
GND
TM
PhotonIC
C 1P
CM9153
C 2N
1.0uF
3.0V to 6.0V
E NA
V IN
1.0uF
© 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
1
PRELIMINARY
CM9153
Package Pinout
PACKAGE / PINOUT DIAGRAM
TOP VIEW
C2P
1
8
C1N
VOUT
2
7
GND
C1P
3
6
C2N
VIN
4
5
ENA
TOP VIEW
BOTTOM VIEW
(Pins Down View)
(Pins Up View)
8 7 6 5
1 2 3 4
GND
PAD
Pin 1
Marking
8 7 6 5
1 2 3 4
CM9153-01MR
8 Lead MSOP Package
CM9153-01DE
8 Lead TDFN Package
Note: This drawing is not to scale.
Ordering Information
PART NUMBERING INFORMATION
Lead-free Finish
Leads
Package
Ordering Part Number1
8
TDFN
CM9153-01DE
8
MSOP
CM9153-01MR
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
[GND - 0.3] to +6.0
[GND - 0.3] to +4.5
[GND - 0.3] to +4.5
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
l
Tel: 408.263.3214
l
Fax: 408.263.7846
l
www.cmd.com
04/26/06
PRELIMINARY
CM9153
Specifications (cont’d)
ELECTRICAL OPERATING CHARACTERISTICS
SYMBOL
VIN
PARAMETER
CONDITIONS
MIN
3.0
VIN Supply Voltage
ISD
Shut-Down Supply
Current
IQ
Quiescent Current
charge pump Circuit
TYP
ENA = 0
MAX
6.0
1
UNITS
V
µA
1600
2500
µA
4.2
4.5
4.7
V
Vin = 3.0V to 3.2V
Iout = 60 mA,
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
150
mA
Fs = 650 kHz,
Iout = 0 mA to 120 mA,
VR LOAD
Load Regulation
Vin = 3.2V to 6.5V
Iout = 0 mA to 90 mA,
VR LIN
IOUT
Line Regulation
Output Current
VOUTR
Output Ripple Voltage
fs
Switching Frequency
Vout = 4.0V
Iout = 60 mA
50
mV
650
kHz
CLK
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
0.4
V
600
mA
ENA
Protection
ILIM
V
Over-current Limit
400
TJSD
Over-temperature Limit
135
°C
THYS
Over-temperature Hysteresis
15
°C
© 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
3
PRELIMINARY
CM9153
Typical Performance Curves
CIN=COUT=C1=C2=1.0μF, TA=25 °C, unless specified
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
Line Regulation
Iout=120mA
4.6
4.5
4.5
4.4
4.4
Vout (V)
4.6
4.3
4.2
4.1
4.3
4.2
4.1
4.0
3.00
4.00
5.00
4.0
3.00
6.00
4.00
Vin (V)
5.00
6.00
Vin (V)
Load Regulation
Switching Frequency - 650kHz
690
4.75
Frequency (kHz)
5 Vin
Vout (V)
4.5
Input Voltage (V)
Line Regulation
Iout=60mA
Vout (V)
4.0
4.50
3.6 Vin
3.4 Vin
4.25
670
85ºC
650
20ºC
630
-40ºC
4.00
10
30
50
70
90
110
610
3.2
3.4
3.6
3.8
4.0
4.2
4.4
4.6
Input Voltage (V)
Load Current (mA)
© 2006 California Micro Devices Corp. All rights reserved.
4
490 N. McCarthy Blvd., Milpitas, CA 95035-5112
l
Tel: 408.263.3214
l
Fax: 408.263.7846
l
www.cmd.com
04/26/06
PRELIMINARY
CM9153
Typical Performance Curves (cont’d)
CIN=COUT=C1=C2=1.0μF, TA=25°C, unless specified
No Load Input Current
Vout vs. Temperature
4.550
2000
4.525
1600
Iq (ȝA)
Vout (V)
Vin = 3.6V
4.500
1200
800
4.475
4.450
-40
-15
10
35
60
85
400
3.2
3.6
4.0
4.4
4.8
5.2
5.6
6.0
Vin (V)
Temperature (ºC)
Vin = 3.8V
Vin, 2V/div
Vout, 2V/div
Iout=120 mA
Iout=60 mA
Iin, 200 mA/div
Vin=3.8V
100 mV/div
1 ms/div
Startup
Output Ripple
© 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
CM9153
Functional Block Diagram
3.0V T O 6.0V
1.0uF
E NA
1.0uF
V IN
C 1P
L DO
Pre- R egulator
C 1N
1.0uF
C 2P
C 2N
1.5x C harge Pump
V OUT
4.5V
1.0uF
OS C
GND
Driver
CM9153
Pin Descriptions
PIN DESCRIPTIONS
LEAD(s)
NAME
DESCRIPTION
1
C2P
This pin is the plus side of charge pump bucket capacitor C2. Connect a 1.0µF
ceramic capacitor between C2N and C2P.
2
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.
3
C1P
This pin is the plus side of charge pump bucket capacitor C1. Connect a 1.0µF
ceramic capacitor with a voltage rating of 10 V or greater between C1N and C1P.
4
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.
5
ENA
Enable pin, active high. By applying a PWM signal to this pin, the LED brightness
can be controlled.
6
C2N
This pin is the minus side of charge pump bucket capacitor C2. Connect a 1.0µF
ceramic capacitor between C2N and C2P.
7
GND
Ground pin.
8
C1N
This pin is the minus side of charge pump bucket capacitor C1. Connect a 1.0µF
ceramic capacitor between C1N and C1P.
© 2006 California Micro Devices Corp. All rights reserved.
6
490 N. McCarthy Blvd., Milpitas, CA 95035-5112
l
Tel: 408.263.3214
l
Fax: 408.263.7846
l
www.cmd.com
04/26/06
PRELIMINARY
CM9153
Application Information
The CM9153 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 CM9153 charge pump is the perfect driver for such
portable applications by providing efficiency, compact
overall size, low system cost and minimal EMI.
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 CM9153 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 and
regulates the converted voltage to 4.5V, ±-5%, enough
to drive the forward voltage drop of white LEDs. The
CM9153 requires only two external switched, or
bucket, capacitors, plus an input and an output capacitor resulting in a compact, low profile design. In many
applications, all these can conveniently be the same
value, 1.0μF, commonly available in a compact 0805
surface mount package.
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.
The CM9153 is intended for white LED applications,
but it can drive most all types of LEDs with a forward
voltage drop of less than 4V.
VOUT
C1
½ VLDO
FB
LDO
VLDO
The LED current is determined by its series resistor,
RLED, and is approximately:
ILED =
C OUT
VIN
C2
½ VLDO
4.5 V − VFWD _ LED
RLED
Typical white LEDs have a forward voltage drop,
VFWD_LED, of 3.5V to 3.7V. Like all 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.
Charge C1 and C2 to ½ V
LDO
VOUT
VIN
C1
C OUT
½ VLDO
FB
LDO
VLDO
C2
½ VLDO
CM9153 Operation
When a voltage exceeding the undervoltage lockout
threshold (UVLO) is applied to the VIN pin, the
CM9153 initiates a softstart cycle, typically lasting
100μS. Softstart limits the inrush current while the output capacitors are charged during the power-up of the
device.
Transfer ½ V LDO charge to top of V
LDO
Figure 1. Switch Operation
© 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
CM9153
Application Information (cont’d)
The CM9153 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 400-mA ~
600-mA) 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.
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.
For an ideal 1.5x charge pump, IIN 1.5 x IOUT, and the
efficiency may be expressed as:
POUT ⎛ VOUT × IOUT ⎞
VOUT
⎟=
≈ ⎜⎜
⎟
PIN
⎝ VIN × 1.5 × IOUT ⎠ 1.5 × VIN
VOUT = 4.5V,
P OUT
η ≈ ------------P IN
4.5V
1.5 × VIN
P OUT
4.5V ------------- ≈ ---------------------P IN
2.0 × V IN
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.
Efficiency
Vout=4.5V
100
The CM9153 charge pump automatically switches
between 2 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 whereas the 1.5x charge
pump is enabled only when the battery input is too low
to sustain the output load.
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:
∴ η≈
The ideal 2x charge pump can be similarly expressed:
Efficiency (%)
When the input voltage is greater than the output voltage, the CM9153 senses this condition and if 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.
1X
85
70
CM9153
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 curves
As can be seen, the CM9153, 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 battery
drain. At higher input voltages, above 4.9V typically
seen when the system is running off an AC adapter,
the CM9153, operating in 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.
© 2006 California Micro Devices Corp. All rights reserved.
8
490 N. McCarthy Blvd., Milpitas, CA 95035-5112
l
Tel: 408.263.3214
l
Fax: 408.263.7846
l
www.cmd.com
04/26/06
PRELIMINARY
CM9153
Application Information (cont’d)
CM9153 Design Examples
Capacitor Selection
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. As a result, X7R or X5R type dielectric is 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.
In the configuration shown in Figure , the brightness is
controlled by the PWM signal applied to ENA.
Decreased Duty Cycle will lower the LED brightness,
See Figure 3 and Figure 4.
C2N, 5V/div
PWM, 20 kHz,
60% D.C., 5V/div
Vout ripple,
200 mV/div
Iin, 200 mA/div
LED Brightness Control
V in
C 2P
C 1P
C 1N
VIN
GND
20 uSec/div
Figure 3. High Brightness Waveforms
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 CM9153.
VOUT
Vin=3.8V
The recommended PWM frequency is between 100 Hz
and 20 kHz. If a frequency of less then 100 Hz 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
C 2N
CM9153 ENA
PWM, 20 kHz,
10% D.C., 5V/div
PWM input
PWM Brightness Control, Lowered Quiescent Current
A PWM signal can be used to control the brightness,
which is more efficient than other solutions that dissipate the unwanted LED current in the series resistors.
It also maintains the white LED color fidelity by avoiding color temperature variations that come with bias
current changes. The LED intensity is determined by
the PWM duty cycle, which can vary from 0% to 100%.
Vout ripple,
200 mV/div
Iin, 200 mA/div
Vin=3.8V
20 uSec/div
Figure 4. Low 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
9
PRELIMINARY
CM9153
Application Information (cont’d)
Camera Flash Application
Many smart phones and PDAs include a digital camera. These compact cameras typically utilize a white
LED flash to illuminate the picture subject in low light
conditions. The CM9153 is easily adapted to such an
application. Figure 6 is a typical application using the
CM9153 as a white LED flash driver, which is ideal for
this application because it is capable of driving up to
120-mA continuous current, or 200mA of pulse current,
from a Li-ion battery. The One-shot is used to create a
single pulse of a set duration to the ENA pin of the
CM9153.
paths. Use a solid ground plane, ideally on the backside of the PCB, which it 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.
The Flash LED modules shown here contain three
matched white LEDs 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
3.6V at the peak pulse current) and the number of parallel modules being driven.
V in
VOUT
C 2P
C 1P
C 1N
VIN
GND
C 2N
R CAT HODE
R CAT HODE
ENA
CM9153
Flash
One- shot
Pulse
t
Figure 6, 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
© 2006 California Micro Devices Corp. All rights reserved.
10 490 N. McCarthy Blvd., Milpitas, CA 95035-5112
l
Tel: 408.263.3214
l
Fax: 408.263.7846
l
www.cmd.com
04/26/06
PRELIMINARY
CM9153
Mechanical Details
TDFN-08 Mechanical Specifications
The CM9153 is supplied in an 8-lead TDFN package.
Dimensions are presented below.
Mechanical Package Diagrams
For complete information on the TDFN-08, see the California Micro Devices TDFN Package Information document.
D
8 7 6 5
PACKAGE DIMENSIONS
TDFN
JEDEC
No.
MO-229 (Var. VCCD-3)=
Leads
8
E
Package
Dim.
Millimeters
Pin 1
Marking
Inches
Min
Nom
Max
Min
Nom
Max
A
0.70
0.75
0.80
0.028
0.030
0.031
1 2 3 4
A1
0.00
0.02
0.05
0.000
0.001
0.002
TOP VIEW
A2
0.55
0.65
0.80
0.022
0.026
0.031
A3
0.20
b
0.18
D
0.25
0.008
0.30
0.007
2.00
D2
0.88
E
0.98
0.46
e
0.56
1.08
0.035
0.20
L
0.20
0.012
0.08 C
0.039
0.043
A1
0.079
0.66
0.018
0.50
K
0.010
0.079
2.00
E2
0.10 C
0.022
A3 A2
A
SIDE VIEW
0.026
0.020
0.008
0.30
0.008
0.012
0.13
R
0.075
r1
0.075
0.018
1 2 3 4
0.005
D2
r1
0.003
0.003
# per
tube
NA
# per
tape and
reel
3000 pieces
E2
L2
0.45
GND PAD
L
R
8 7 6 5
K
Controlling dimension: millimeters
b
e
8X
=This package is compliant with JEDEC standard MO-229, variation
VCCD-3 with exception of the "D2" and "E2" dimensions as called
out in the table above and the "r1" dimension which is not specified in
the MO-229 standard.
BOTTOM VIEW
0.10
M
CAB
Package Dimensions for 8-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
11
PRELIMINARY
CM9153
Mechanical Details (cont’d)
MSOP-8 Mechanical Specifications:
Mechanical Package Diagrams
The CM9153-01MR is supplied in a 8-pin MSOP package. Dimensions are presented below.
TOP VIEW
For complete information on the MSOP-8, see the California Micro Devices MSOP Package Information document.
D
8
PACKAGE DIMENSIONS
Package
MSOP
Pins
8
Dimensions
Min
Max
A
0.87
1.17
0.034
0.046
A1
0.05
0.25
0.002
0.010
B
0.30 (typ)
0.012 (typ)
C
0.18
0.007
E
2.90
3.10
0.114
0.114
0.65 BSC
0.025 BSC
0.193 BSC
# per tape
and reel
SEATING
PLANE
0.017
3
4
A1
B
0.122
4.90 BSC
0.64
2
SIDE VIEW
0.122
e
0.43
1
A
H
L
E
Inches
Max
3.10
5
Pin 1
Marking
Millimeters
2.90
6
H
Min
D
7
e
END VIEW
0.025
C
4000 pieces
Controlling dimension: inches
L
Package Dimensions for MSOP-8
© 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
l
www.cmd.com
04/26/06