1
Rev. 3/19/01 SP4439 Ultra-Quiet Electroluminescent Lamp Driver With Programmable Waveshape Copyright 2001 Sipex Corporation
DESCRIPTION
The SP4439 device is a low noise, high voltage output DC-AC inverter designed to drive
electroluminescent lamps that backlight liquid crystal display and keypads used in cellular
phones, cordless phones, 2-way radios, and other wireless communication products. The output
waveform of the SP4439 device is ideal for cell phone applications requiring low acoustic noise
performance. One external resistor is used to set the internal oscillator frequency and one inductor
is required to generate the high voltage AC output to drive an EL lamp up to 6 square inches in
size. The device gives the customer flexibility to define waveform rise and fall times, to optimize
noise performance, and to optimize efficiency for customer specific applications. The SP4439
typically operates from a +3.0V battery source and has a low power standby mode that draws less
than 125nA, making it ideal for low-power cellular applications. All input pins are ESD protected
with internal diodes to V
DD
and V
SS
. The SP4439 is offered in a space-saving 10-pin MSOP package.
Ultra-Quiet Electroluminescent Lamp Driver
with Programmable Wave Shape
SP4439
V
SS
COIL
C
INT
SP4439
V
BATT
C1
0.1
F
L1
820
H/14
6
2
3
7
5
ELEN
D1
1N4148
C
INT
47nF
V
DD
EL2
EL1
EL Lamp
8
10
4
R
OSC
681k
C2
1nF
R
OSC
R
D
1.1k
1
R
C
2.21k
9
R
D
R
C
s
User Programmable Waveshape Via Two External
Resistors
s
Patent Pending Low Noise Output Waveshaping
s
Waveshaped Output For Low Acoustic Noise and
Maximum Efficiency
s
Reduced Supply Current And Standby Current
s
Waveshaped Output And Low Frequency Operation
Minimizes Stress On EL Lamp To Extend Its
Lifetime
s
Uses Low Profile 820
H Coils
s
Waveform With Gradual Rising And Falling Edges
Minimizes EMI
s
+2.2V To +5.0V Battery Operation
s
Space-Saving 10-pin MSOP package
APPLICATIONS
s
Cellular Radios
s
Wireless Communication
Prod
uct
V
DD
C
INT
EL1
ELEN
R
OSC
COIL
EL2
V
SS
R
C
R
D
1
2
10
9
8
7
6
3
4
5
SP4439
10 Pin MSOP
Rev. 3/19/01 SP4439 Ultra-Quiet Electroluminescent Lamp Driver With Programmable Waveshape Copyright 2001 Sipex Corporation
2
ABSOLUTE MAXIMUM RATINGS
These are stress ratings only and functional operation
of the device at these ratings or any other above those
indicated in the operation sections of the specifications
below is not implied. Exposure to absolute maximum
rating conditions for extended periods of time may
affect reliability.
Supply Voltage (V
DD
to V
SS
)........................-0.3V, +5V
Operating Temperature.......................-40C to +85C
Storage Temperature........................-65C to +150C
Power Dissipation Per Package
10-pin MSOP
(derate 4.85mW/
O
C above +70
O
C).........................720mW
SPECIFICATIONS
V
DD
= +3.0V, L
COIL
= 820
H/14
, R
OSC
= 714k
, EL Lamp Load = (8nF + 2.5k
)/1M
, and T
AMB
= -40
O
C to +85
O
C.
T
AMB
= 25
O
C for typical values unless otherwise noted.
NOTE 1: Audible Noise is measured inside an acoustic sound chamber. The Sound Level Meter is a B&K Mediator 2238, A-
weighted with Condenser Mic type 4188 positioned 1/4 inch above the lamp in an 8 cubic inch volume. See Figure 5 on page 6.
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STORAGE CONSIDERATIONS
Storage in a low humidity environment is preferred. Large high
density plastic packages are moisture sensitive and should be
stored in Dry Vapor Barrier Bags. Prior to usage, the parts
should remain bagged and stored below 40
C at 60%RH. If the
parts are removed from the bag, they should be used within 48
hours or stored in an environment at or below 20%RH. If the
above conditions cannot be followed, the parts should be baked
for four hours at 125
C in order remove moisture prior to
soldering. Sipex ships product in Dry Vapor Barrier Bags with a
humidity indicator card and desiccant pack. The humidity
indicator should be below 30%RH.
3
Rev. 3/19/01 SP4439 Ultra-Quiet Electroluminescent Lamp Driver With Programmable Waveshape Copyright 2001 Sipex Corporation
PIN ASSIGNMENTS
PINOUT
V
DD
C
INT
EL1
ELEN
R
OSC
COIL
EL2
V
SS
R
C
R
D
1
2
10
9
8
7
6
3
4
5
SP4439
10 Pin MSOP
Pin Number
Pin Symbol
Description
1
R
D
Discharge Rate Set Resistor. Connect the discharge rate set
resistor from this pin to ground.
2
V
DD
Positive Battery Power Supply. Connect such that +2.2V < V
DD
< +5.0V.
3
ELEN
Electroluminescent Lamp Enable. When driven HIGH, this input
pin enables the EL driver outputs for EL1 and EL2. This pin has
an internal pulldown resistor.
4
R
OSC
Oscillator Resistor. Connecting a resistor to this input pin sets the
frequency of the internal clock.
5
V
SS
Power Supply Common. Connect to the lowest circuit potential,
typically ground.
6
COIL
The inductor for the EL lamp is connected from V
DD
to this input
pin.
7
C
INT
Integrating Capacitor. An integrating capacitor (47nF typical)
connected from this pin to ground filters out any coil switching
spikes or ripple present in the output waveform to the EL lamp.
Connecting a fast recovery diode from COIL to C
INT
increases the
light output of the EL lamp.
8
EL2
Electroluminescent Lamp Output 2. This is a high voltage lamp
driver output pin to connect to the EL lamp.
9
R
C
Charge Rate Set Resistor. Connect the charge rate set resistor
from this pin to pin 7, the integrating capacitor.
10
EL1
Electroluminescent Lamp Output 1. This is a high voltage lamp
driver output pin to connect to the EL lamp.
Rev. 3/19/01 SP4439 Ultra-Quiet Electroluminescent Lamp Driver With Programmable Waveshape Copyright 2001 Sipex Corporation
4
Figure 2: Internal Block Diagram of the SP4439
V
SS
COIL
C
INT
SP4439
V
BATT
C1
0.1
F
L1
820
H/14
6
2
3
7
5
ELEN
D1
1N4148
C
INT
47nF
V
DD
EL2
EL1
EL Lamp
8
10
4
R
OSC
681k
C2
1nF
R
OSC
R
D
1.1k
1
R
C
2.21k
9
R
D
R
C
Figure 1: Typical Operating Circuit for the SP4439
Figure 3: EL Differential Output Waveform of the EL1
and EL2 Outputs of the SP4439
Figure 5. Electroluminescent Lamp Noise Measurement
Setup for the SP4439
Figure 4: Dual Supply Application Circuit for the
SP4439
V
SS
COIL
C
INT
SP4439
V
CONTROL
= +2.7V to +3.3V
C1
0.1
F
L1
6
2
3
7
5
ELEN
D1
1N4148
C
INT
V
DD
EL2
EL1
EL Lamp
8
10
4
R
OSC
C2
1nF
R
OSC
V
POWER
= +2.7V to +9.0V
9
R
C
2.2
K
47nF
820
H/14
1
1.1K
R
D
HP8903A Audio Analyzer - SPCL 3.1, 1.17
Preamplifier with 30kHz High Pass Filter
Tek754C Digital Osciliscope
Voltage Waveform Measurements
EL Driver
Differential
Voltage Probe
Current
Probe
Monitor
Aux 1
Bruel & Kjaer
2238 Mediator
A-Weighting
dBSPL
Measurement
EL Lamp Noise Measurement Set-Up
Anechoic Chamber
Microphone
Type 4188
Photometer
Tek-J17
4"
2"
1"
EL
Lamp
FF7
Q
Q
V
BATT
L1
820
H/14
EL Lamp
10
8
5
V
SS
C
INT
COIL
EL2
EL1
C
INT
47nF
ELEN
D1
1N4148
V
DD
4
3
6
7
2
DMOS
DMOS
PMOS
PMOS
BRIDGE
CONTROL
C1
0.1
F
R
OSC
681k
C2
1nF
R
OSC
SP4439
OSC
R
D
1.1k
R
C
2.21k
R
C
9
1 R
D
5
Rev. 3/19/01 SP4439 Ultra-Quiet Electroluminescent Lamp Driver With Programmable Waveshape Copyright 2001 Sipex Corporation
DESCRIPTION
The SP4439 electroluminescent lamp (EL) driver
is a low-cost low voltage device ideal for the
replacement of LED backlighting designs in cell
phones, PDAs and other portable designs
requiring low acoustic noise. The SP4439
contains a DC-AC inverter that can produce an
AC output of 160V
P-P
(typical) from +3.0V input
voltage. An internal block diagram of the SP4439
can be found in Figure 2.
The SP4439 is built on Sipex's dielectrically
isolated BiCMOS process that provides the
isolation required to separate the high voltage
AC signal used to drive the EL lamp from the low
voltage logic and signal processing circuitry.
This ensures latch-up free operation in the
interface between the low voltage CMOS
circuitry and the high voltage bipolar circuitry.
The SP4439 is ideal for applications driving EL
lamps to backlight LCD displays and keypads,
used in cellular radios.
Electroluminescent Technology
An EL lamp is a strip of plastic that is coated with
a phosphorous material which emits light
(fluoresces) when a (>40V) AC signal is applied
across it. Long periods of DC voltages applied
to the lamp tends to breakdown the material and
reduce its lifetime. With these considerations in
mind, the ideal signal to drive an EL lamp is a
high voltage sine wave. Traditional approaches
to achieving this type of waveform included
discrete circuits incorporating a transformer,
transistors, and several resistors and capacitors.
This approach is large and bulky, and cannot be
implemented in most hand held equipment. Sipex
offers low power single chip driver circuits
specifically designed to drive small to medium
sized electroluminescent panels.
Market Applications
Electroluminescent backlighting is ideal when
used with LCD displays, keypads, or other backlit
readouts. Its main use is to illuminate displays in
dim to dark conditions for momentary periods of
time. EL lamps consume less power than LEDs
or incandescent bulbs making them ideal for
battery powered products. Also, EL lamps are
able to evenly light an area without creating any
undesirable "hot spots" in the display.
THEORY OF OPERATION
The SP4439 is a DC-AC inverter made up of an
oscillator/frequency divider, a coil/boost
converter, a switched H-bridge network, and a
precision bridge control logic.
The Oscillator/Frequency Divider
The oscillator provides the SP4439 with an on-
chip clock used to control the coil switch (f
COIL
)
and the H-bridge network (f
LAMP
). Although the
oscillator frequency can be varied to optimize
the lamp output, the ratio of f
COIL
/f
LAMP
will
always equal 128.
Figure 2 shows the oscillator output driving the
coil and through 7 flip flops, driving the lamp.
The suggested oscillator frequency is 32kHz for
f
COIL
. The oscillator output is internally divided
down by 7 flip flops to create a second internal
control signal at 250Hz for f
LAMP
.
The Coil/Boost Converter
The supply V
COIL
can range from +2.7V to +9V.
See figure 4 on page 6. V
COIL
should be chosen
such that I
COIL
does not exceed the maximum
coil current specification. The majority of the
current goes through the coil and is typically
much greater than I
DD
.
The inductor is an external component connected
from V
COIL
to the COIL pin of the SP4439.
Energy is stored in the coil according to the
equation
E
L
= 1/2 x L x I
P2
where I
P
, to the first approximation, is the product
I
P
= (t
ON
) x ((V
BATT
- V
CE
)/L)
where t
ON
is the time it takes for the coil to reach
its peak current, V
CE
is the voltage drop across
the internal NPN transistor and L is the inductance
of the coil. When the NPN transistor switch is
off, the energy is forced through an internal
diode which drives the switched H-bridge
network. This energy recovery is directly related
to the brightness of the EL lamp output. There
are many variations among coils; magnetic
material differences, winding differences and
parasitic capacitances.
Rev. 3/19/01 SP4439 Ultra-Quiet Electroluminescent Lamp Driver With Programmable Waveshape Copyright 2001 Sipex Corporation
6
The f
COIL
signal controls a switch that connects
the coil at the COIL pin to ground or to open
circuit. The f
COIL
signal is a 90% duty cycle
signal switching at the oscillator frequency,
32kHz. During the time when the f
COIL
signal is
HIGH, the coil is connected from V
COIL
to ground
and a charged magnetic field is created in the
coil. When the f
COIL
signal is LOW, the ground
connection is switched open, the field collapses,
and the energy in the inductor is forced to flow
toward the high voltage H-bridge switches.
The Switched H-Bridge Network
Current sources and precision controlled timing
of the SP4439 switched H-bridge network are
designed to reduce EMI emissions, extend EL
lamp life, and reduce the overall power dissipation
of the device.
Current sources were added to the high and low
side of the H-bridge network to ensure control of
the charge and discharge of the EL lamp. The
precision MOSFET timing of the SP4439 allows
for controlled charging and discharging of the
EL lamp to minimize EMI and audible noise.
Refer to Figure 7 for the single ended and
differential output waveforms to the EL lamp.
The Precision Bridge Control Circuitry
This circuitry is driven by the internal oscillator
to control the timing of the charge and discharge
of the EL lamp to eliminate EMI and noise
concerns. This control circuitry drives the H-
bridge timing. Refer to Figure 2 for the internal
block diagram of the SP4439.
Fine Tuning Performance
Circuit performance of the SP4439 can be
improved with some of the following suggestions:
Increase EL Lamp Light Output: By
connecting a fast recovery diode from COIL
(pin 5) to C
INT
(pin 6), the internal diode of the
switched H-bridge network is bypassed resulting
in an increase in light output at the EL lamp. We
suggest a fast recovery diode, such as the industry
standard 1N4148, be used for D1. This circuit
connection can be found in Figures 1 and 2.
By adjusting the values of R
C
and R
D
the rate of
change and discharge can be adjusted. Faster
rise time typically means greater light output and
greater noise. The more gradual the rise and fall
edges are, the less noise is produced by the
lamps. For example a sign wave would not
generate any noise.
Changing the EL Lamp Output Voltage
Waveform
: Designers can alter the trapezoidal
output voltage waveform to the EL Lamp.
Changing the capacitance of the integrating
capacitor, C
INT
, will ideally integrate the output
waveform making it appear more sinusoidal.
This will minimize any noise inherent to the
application.
Programming the Ultra-Quiet SP4439
Output Voltage Wave-shape:
The optimal
low noise wave-form to drive an EL lamp is a
sinusoid. The drawbacks of using a sine wave to
drive an EL lamp are twofold. First, the luminance
of an EL lamp is proportional to the root mean
square value of the applied voltage. Second, a
high voltage sine wave generator is difficult to
design due to inefficiencies and space constraints.
The first problem can be overcome by using a
square wave to drive the lamp. This is the most
efficient waveform and has the highest RMS
voltage but it creates the highest noise when
applied to an EL lamp. Sipex has found the best
trade off between noise and luminance is a
trapezoid or clipped sinusoid waveform.
The SP4439 output wave-shape is programmable
in terms of its rise and fall times. The output
waveform seen across the lamp terminals is
actually generated as a single ended waveform
and is measured differentially. This is shown in
figure 7.
The single ended waveform can be broken up
into three regions: A charge region, a hold
region and a discharge region. The differential
rise-time actually encompasses both a charge
and a discharge region.
The charge and discharge regions are controlled
independently by two resistors: RC is the charge
resistor and RD is the discharge resistor. The
rise-time (tr) is defined as 800uS for the
differential waveform. Therefore the single ended
charge time is one half that or 400uS. Use the
following to find the full-scale charge time:
t
r
= T
2
-T
1
/
1.25
(1.25) where T
2
- T
1
is the full scale
7
Rev. 3/19/01 SP4439 Ultra-Quiet Electroluminescent Lamp Driver With Programmable Waveshape Copyright 2001 Sipex Corporation
time of 1ms, and a charge or discharge time of
500
S. V
BIASC
= 2.8V, V
BIASD
= 1.4V.
Example 1- Lamp Size = 2in
(12.9cm
2
):
A typical 2in
2
(12.9cm
2
) lamp has a capacitance
of 8nF. Given the typical output peak voltage of
80V, the charge resistor can be calculated using
equation 4.
R
C
=
(
V
BIASC
x
T
)
C
x C
EL
R
C
= (2.8V x 500uS) / (80V x 8nF) = 2188
R
D
= (1.4V x 500uS) / (80V x 8nF) = 1094
Example 2- Lamp Size = 4in
2
(25.8cm
2
):
If we assume the lamp capacitance doubles to
16nF then:
R
C
= (2.8V x 500uS) / (80V x 16nF) = 1094
R
D
= (1.4V x 500uS) / (80V x 16nF) = 547
Notes:
If the factors such as peak voltage and lamp
frequency are different, adjustment must be made
to those values in the resistance equations. There
are limitations to what the waveform will look
like. For example if the resistors are set small,
the times become fast and a step will appear at
the zero crossing point of the waveform. The
intent of the waveform programmability is to
allow the use of a wide range of lamp sizes while
maintaining a smooth waveform to minimize
audible noise.
Keep in mind that coil values and the oscillator
frequency may have to be changed to support a
given luminance for a particular lamp size. It is
best to define these parameters first and then go
back and calculate the charge and discharge
resistors.
Audio Noise Considerations:
A system can have different sources of audio
noise, The coil the filter capacitor, and the EL
lamp itself may be a source of audio noise if
operated in the audio frequency range.
Designers should select either the coil or coil
frequency such that the coil is not in continous
mode as this will greatly decrease efficiency and
contribute to noise.
Close attention should be given to the mounting
This simply means that for a rise-time
measurement of 400
s, the full-scale time is
500uS.
The ultimate goal here is to calculate the values
for the charge and discharge resistors R
C
and R
D
respectively. These two resistors define a constant
charge current I
C
and discharge current I
D
. The
combination of the lamp capacitance and the
constant charge currents results in the rise and
fall waveform. Lets start by calculating the
constant currents.
The charge current is defined as:
I
C
=
V
BIASC
(1)
R
C
where V
BIASC
is defined internally to be 2.8V.
The discharge current is defined as:
I
C
=
V
BIASD
(2)
R
D
where V
BIASD
is defined internally to be 1.4V.
The charge and discharge currents should be
equal to give smooth rise and fall times. Once the
currents are known, the charge or discharge time
is defined by:
T = C
EL
V
(3)
I
C,D
where C
EL
is the lamp capacitance, and
V is the
output voltage at the C
INT
node.
Subsituting equations 1 or 2 into equation 3 gives
the equation to calculate the charge resistor
directly:
T = C
EL
(
V
)
,
T = C
EL
(
V x R
C
)
, R
C
=
(
V
BIASC
x
T
)
(4)
V
BIASC
V
BIAS
V x C
EL
R
C
The proper way to approach the SP4493 system
design is to first measure the capacitance of the
lamp intended for the application. The
capacitance of an EL lamp is proportional to the
area of the lamp. Lamps from different
manufacturers will exhibit different capacitance/
area values. Therefore it is important to measure
a lamp from the lamp manufacturer that will be
used in production. The following examples
assume the nominal lamp frequency is set to
250Hz. This defines a rise-time of 800uS, a total
Rev. 3/19/01 SP4439 Ultra-Quiet Electroluminescent Lamp Driver With Programmable Waveshape Copyright 2001 Sipex Corporation
8
Figure 6. Evaluation Board Layout for the SP4439.
EVALUATION BOARD LAYOUT
(ENLARGED)
EVALUATION BOARD LAYOUT
(ACTUAL SIZE)
of the filter capacitor where the mounting can act
as an amplifier, such as in a speaker box. Film
capacitors do not exhibit audio noise concerns
but certain ceramic capacitors subjected to a
high voltage source can exhibit a piezoelectric
effect. This can be a source of concern in the
audio range.
The EL lamp itself can also exhibit audible noise
as a result of high voltage swings at frequencies
within the audio range. Close attention should
be given to the physical mounting of the EL lamp
to diminish this concern that can generate both
EMI and audio noise.
Electromagnetic Interference (EMI)
Considerations:
Electromagnetic Interference
(EMI) concerns are rooted in uncontrolled high
voltage swings on the EL lamp. The controlled
charging and dischanging of the EL lamp by the
SP4439 minimizes EMI effects.
Printed Circuit Board Layout Suggestions:
The SP4439's high voltage operation makes PC
layout important for minimizing ground bounce
and noise. Keep the IC's GND pin and the
ground leads of C1 and C
INT
less than 0.2 in
(5mm) apart. Also keep the connections to
COIL as short as possible. To maximize output
power and efficiency and minimize output ripple
voltage, use a ground plane and solder the IC's
V
SS
directly to the ground plane.
EL Lamp Driver Design Challenges
There are many variables which can be optimized
for specific applications. The amount of light
emitted is a function of the voltage applied to the
lamp, the frequency at which it is applied, the
lamp material and the lamp size.
A number of characterization curves to assist in
the selection of lamp size and performance
optimization have been included here (Figures 8
to 17). In addition, Sipex will perform customer
application evaluations, using the customer's
actual EL lamp to determine the optimum
operating conditions for specific applications.
For customers considering an EL backlighting
solution for the first time, Sipex is able to offer
retrofitted solutions to the customer's existing
LED or non-backlit product for a thorough
electrical and cosmetic evaluation. Refer to
Figure 6 for an enlargement and actual size
evaluation board layout. Please contact your
local Sales Representative for Sipex or the Sipex
factory directly to initiate this valued service.
9
Rev. 3/19/01 SP4439 Ultra-Quiet Electroluminescent Lamp Driver With Programmable Waveshape Copyright 2001 Sipex Corporation
Figure 8. The SP4439 supply current remains at 20mA,
independent of EL lamp area.
Figure 7. Single Ended and Differential Output
Waveforms for the SP4439. CH1 and CH2 are single
ended waveform. CH4 is a differential waveform.
0
5
10
15
20
25
1.0 1.2
1.4 1.6
1.8 2.0
2.2
2.4
2.6 2.8
3.0
Lamp Size (in
2
)
I
DD
(mA)
Figure 9. The V
PP
lamp voltage decreases with
increasing EL lamp size for a fixed set of circuit
conditions like those identified in Figures 1 and 2.
Lower V
PP
means a less brightly lit lamp.
Figure 11. Lamp frequency remains relatively constant
over the bias supply voltage. Lamp light does not visibly
decrease over the typical battery operating range.
Figure 10. Luminance of the EL lamp as a function of
its size. For a fixed set of circuit conditions, lamp
brightness decreases as a function of lamp size.
Figure 12. Peak lamp voltage increases almost linearly
with increasing supply bias voltage. Increasing the
supply increases lamp brightness.
0
20
40
60
80
100
120
140
160
180
200
Output Voltage (V
P-P
)
1.0 1.2
1.4 1.6
1.8 2.0
2.2
2.4
2.6 2.8
3.0
Lamp Size (in
2
)
0
5
10
15
20
25
1.0
1.5
2.0
3.0
Lamp Size (in
2
)
Luminance (cd/m
2
)
30
2.5
250
255
260
265
270
275
2.5
2.9
3.1
3.5
V
DD
(Volts)
Lamp Frequency (Hz)
280
3.3
2.7
3.7
120
130
140
150
160
170
2.5
2.9
3.1
3.5
V
DD
(Volts)
Lamp Voltage (V
P-P
)
180
3.3
2.7
3.7
Rev. 3/19/01 SP4439 Ultra-Quiet Electroluminescent Lamp Driver With Programmable Waveshape Copyright 2001 Sipex Corporation
10
Figure 14. EL lamp brightness increases with
increasing bias supply voltage.
Figure 13. Overall supply current increases almost
linearly with increasing bias supply voltage.
Figure 15. Lamp frequency remains stable over the
operating temperature range for a fixed set of circuit
conditions.
Figure 17. Circuit supply current is very stable of the
typical operating range.
Figure 16. Lamp peak voltage remains relatively
constant over the typical operating temperature range.
15
17
19
21
23
25
2.5
2.9
3.1
3.5
V
DD
(Volts)
27
3.3
2.7
3.7
I
CC
(mA)
10
14
16
18
20
22
2.5
2.9
3.1
3.5
V
DD
(Volts)
24
3.3
2.7
3.7
Luminance (cd/m
2
)
12
200
210
250
260
270
280
290
300
-40
-20
0
20
40
60
80
Temperature (
C)
Lamp Frequency (Hz)
220
230
240
120
140
145
150
155
160
-40
-20
0
20
40
60
80
Temperature (
C)
125
130
135
Peak Lamp Voltage (Volts)
15
16
20
21
22
23
24
25
-40
-20
0
20
40
60
80
Temperature (
C)
Supply Current
17
18
19
11
Rev. 3/19/01 SP4439 Ultra-Quiet Electroluminescent Lamp Driver With Programmable Waveshape Copyright 2001 Sipex Corporation
Hitachi Metals
Material Trading Division
2101 S. Arlington Heights Road,
Suite 116
Arlington Heights, IL 60005-4142
Phone: 1-800-777-8343 Ext. 12
(847) 364-7200 Ext. 12
Fax: (847) 364-7279
Hitachi Metals Ltd. Europe
Immernannstrasse 14-16, 40210
Dusseldorf, Germany
Contact: Gary Loos
Phone: 49-211-16009-0
Fax: 49-211-16009-29
Hitachi Metals Ltd.
Kishimoto Bldg. 2-1, Marunouchi
2-chome, Chiyoda-Ku, Tokyo, Japan
Contact: Mr. Noboru Abe
Phone: 3-3284-4936
Fax: 3-3287-1945
Hitachi Metals Ltd. Singapore
78 Shenton Way #12-01,
Singapore 079120
Contact: Mr. Stan Kaiko
Phone: 222-8077
Fax: 222-5232
Hitachi Metals Ltd. Hong Kong
Room 1107, 11/F., West Wing,
Tsim Sha. Tsui Center 66
Mody Road,Tsimshatsui East,
Kowloon, Hong Kong
Phone: 2724-4188
Fax: 2311-2095
Panasonic
6550 Katella Ave
Cypress, CA 90630-5102
Phone: (714) 373-7366
Fax: (714) 373-7323
Sumida Electric Co., LTD.
5999, New Wilke Road,
Suite #110
Rolling Meadows, IL,60008 U.S.A.
Phone: (847) 956-0666
Fax: (847) 956-0702
Sumida Electric Co., LTD.
4-8, Kanamachi 2-Chrome,
Katsushika-ku, Tokyo 125 Japan
Phone: 03-3607-5111
Fax: 03-3607-5144
Sumida Electric Co., LTD.
Block 15, 996, Bendemeer Road
#04-05 to 06, Singapore 339944
Republic of Singapore
Phone: 2963388
Fax: 2963390
Sumida Electric Co., LTD.
14 Floor, Eastern Center, 1065
King's Road, Quarry Bay,
Hong Kong
Phone: 28806688
Fax: 25659600
Murata
2200 Lake Park Drive, Smyrna
Georgia 30080 U.S.A.
Phone: (770) 436-1300
Fax: (770) 436-3030
COIL MANUFACTURERS
Leading Edge Ind. Inc.
11578 Encore Circle
Minnetonka, MN 55343
Phone 1-800-845-6992
Midori Mark Ltd.
1-5 Komagata 2-Chome
Taita-Ku 111-0043 Japan
Phone: 81-03-3848-2011
Luminescent Systems inc. (LSI)
101 Etna Road
Lebanon, NH. 03766-9004
Phone: (603) 448-3444
Fax: (603) 448-3452
NEC Corporation
Yumi Saskai
7-1, Shiba 5 Chome, Minato-ku,
Tokyo 108-01, Japan
Phone: (03) 3798-9572
Fax: (03) 3798-6134
Seiko Precision
Shuzo Abe
1-1, Taihei 4-Chome,
Sumida-ku, Tokyo, 139 Japan
Phone: (03) 5610-7089
Fax: (03) 5610-7177
Gunze Electronics
2113 Wells Branch Parkway
Austin, TX 78728
Phone: (512) 752-1299
Nitto Denko
Yoshi Shinozuka
Bayside Business Park 48500
Fremont, CA. 94538
Phone: 510 445 5400
Fax: 510 445-5480
Top Polarizer- NPF F1205DU
Bottom - NPF F4225
or (F4205) P3 w/transflector
TRANSFLECTOR MATERIAL
Astra Products
Mark Bogin
P.O. Box 479
Baldwin, NJ 11510
Phone (516)-223-7500
Fax (516)-868-2371
Murata European
Holbeinstrasse 21-23, 90441
Numberg, Postfachanschrift 90015
Phone: 011-4991166870
Fax: 011-49116687225
Murata Taiwan Electronics
225 Chung-Chin Road, Taichung,
Taiwan, R.O.C.
Phone: 011 88642914151
Fax: 011 88644252929
Murata Electronics Singapore
200 Yishun Ave. 7, Singapore
2776, Republic of Singapore
Phone: 011 657584233
Fax: 011 657536181
Murata Hong Kong
Room 709-712 Miramar Tower, 1
Kimberly Road, Tsimshatsui,
Kowloon, Hong Kong
Phone: 011-85223763898
Fax: 011-85223755655
POLARIZERS/TRANSFLECTOR MANUFACTURERS
EL LAMP MANUFACTURERS
Rev. 3/19/01 SP4439 Ultra-Quiet Electroluminescent Lamp Driver With Programmable Waveshape Copyright 2001 Sipex Corporation
12
PACKAGE: 10-PIN MSOP PACKAGE
(ALL DIMENSIONS IN MILLIMETERS)
1
0.50
BSC
3.00
0.10
2
2.95
0.10
0.86
0.08
1.10 MAX
0.10
0.05
3.00
0.10
3.00
0.10
0.95BSC
0.55
0.15
0.30 to 0.07
0.41
0.08
2.95
0.10
3.0
o
3.0
o
2.95
0.10
0.51
0.13
0.51
0.13
0.25
0.31
0.08
4.90
0.15
0.50
BSC
12.0
o
3.0
o
12.0
o
3.0
o
0.30 to 0.07
0.23
0.07
13
Rev. 3/19/01 SP4439 Ultra-Quiet Electroluminescent Lamp Driver With Programmable Waveshape Copyright 2001 Sipex Corporation
Sipex Corporation reserves the right to make changes to any products described herein. Sipex does not assume any liability arising out of the
application or use of any product or circuit described herein; neither does it convey any license under its patent rights nor the rights of others.
The information furnished by Sipex has been carefully reviewed for accuracy and reliability. Its application or use, however, is solely the responsibility of the
user. No responsibility for the use of this information become part of the terms and conditions of any subsequent sales agreement with Sipex. Specifications
are subject to change without responsibility for any infringement of patents or other rights of third parties which may result from its use. No license or other
proprietary rights are granted by implication or otherwise under any patent or patent rights of Sipex Corporation.
Corporation
ORDERING INFORMATION
Model
Operating Temperature Range
Package Type
SP4439EU .............................................. -40C to +85C ........................................ 10-Pin MSOP
SP4439UEB ........................................................................................................ Evaluation Board
SIGNAL PROCESSING EXCELLENCE
Sipex Corporation
Headquarters and Main Offices:
22 Linnell Circle
Billerica, MA 01821
TEL: (978) 667-8700
FAX: (408) 670-9001
e-mail: sales@sipex.com
233 South Hillview Drive
Milpitas, CA 95035
TEL: (408) 934-7500
FAX: (408) 935-7600
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