View SP4403_283697.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

(R)
SP4403
Low Voltage Electroluminscent Lamp Driver
s High Efficiency Design s +2.2V to +5.0V Battery Operation s DC-to-AC Converter Produces up to 220VP-P for EL Display Panels s Single Resistor Controlled Internal Oscillator s Low Current Standby Mode Draws Less than 1A s Uses Small 470H, Sub 2mm Height Coil APPLICATIONS s PDA's s Pagers s Cellular Phones s LCD Modules s Handheld GPS Units DESCRIPTION The SP4403 is a high voltage output DC-AC inverter specifically designed to drive electroluminescent lamps to backlight liquid crystal displays, keypads, and backlit readouts used in battery operated portable equipment. The SP4403 will operate from a +2.2V to +5.0V battery source. The device features a low power shutdown mode which draws less than 100nA (typical), ideal for low power portable products. One external inductor is required to generate the high voltage AC output. One external resistor is used to select the internal oscillator frequency. The SP4403 is ideal for portable applications such as PDA's, pagers, cellular phones, and other portable applications using LCDs in dim or low light environments. The SP4403 is offered in 8 pin MSOP packages.
VBATT
ELEN
1
ELEN 1 VSS 2 COIL 3 EL1 4 SP4403
8 ROSC
VDD
L1 470H/12
SP4403
6 3 COIL D1* 1N4148 ROSC 450k
7 CINT 6 5 VDD EL2
C1* 1.0F
ROSC
8
7
CINT
C2 10nF
2 VSS
4 EL1
5 EL2
CINT* 680pF
EL Lamp
*Optional Device
Rev. 7/16/01
SP4403 Electroluminescent Lamp Driver
(c) Copyright 2001 Sipex Corporation
1
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. Power Supply, VBATT.............................................7.0V Input Voltages, ELEN (pin 1)........-0.5V to (VDD+0.5V) Lamp Outputs..................................................250VP-P Operating Temperature.......................-40C to +85C Storage Temperature........................-65C to +150C Power Dissipation Per Package
8-pin MSOP (derate 4.85mW/OC above +70OC).........400mW
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 40C and 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 125C 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. 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 of 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 no responsibility for any infringement of patents or other rights of third parties which may result from its use. No license or proprietary rights are granted by implication or otherwise under any patent or patent rights of Sipex Corporation.
SPECIFICATIONS
VBATT = 3.0V, TAMB = 25C, L1 = 470H/12, ROSC = 450k, CLAMP = 15nF/35nF, CINT = 680pF, C1 = 1.0F, and C2 = 10nF unless otherwise noted.
PARAMETER Supply Voltage, VDD Supply Current, IDD Supply Current, ICOIL +IDD Coil Voltage, VCOIL ELEN Input Voltage, VELEN LOW: EL off HIGH: EL on
MIN. 2.2
TYP. 3.0 1.5 3.8 45 65
MAX. 5.0 3.0 6.0 65 95 9.0
UNITS V mA
CONDITIONS
VDD = VCOIL = 3.0V VDD = VCOIL = 5.0V VDD = VCOIL = +3.0V VDD = VCOIL = +5.0V
mA V
VDD -0.25 VDD*0.61 1.7V 0 VDD 0.05
0.25V VDD+0.25 1.0
V
VDD = 2.8V - 5.0V VDD = 2.2V - 2.8V VDD = VCOIL = 5.0V
Shutdown Current, ISD = ICOIL +IDD INDUCTOR DRIVE Coil Frequency, fCOIL Coil Duty Cycle Peak Coil Current, IPK-COIL EL LAMP OUTPUT EL Lamp Frequency, fLAMP Peak to Peak Output Voltage, VPP 330 170 170 40.9 85
A
51.2 90
64.0 95 85
kHz % mA
400 195 200
510
Hz VPP
VDD = VCOIL = 2.2V to 5.0V VDD = VCOIL = +3.0V, CLAMP = 15nF VDD = VCOIL = +5.0V, CLAMP = 35nF
Rev. 7/16/01
SP4403 Electroluminescent Lamp Driver
(c) Copyright 2001 Sipex Corporation
2
PINOUT
ELEN 1 VSS 2 COIL 3 EL1 4 SP4403
8 ROSC 7 CINT 6 5 VDD EL2
PIN ASSIGNMENTS
Pin Name Pin Number Description
1
ELEN
Electroluminescent Lamp Enable. When driven HIGH, this input pin enables the EL driver output EL1 and EL2 (pins 4 and 5, respectively) to the EL lamp. Power Supply Common. Connect to the lowest circuit potential, typically ground. Coil. The inductor for the EL lamp is connected from VBATT to this input pin. Electroluminescent Lamp. This is a lamp driver output pin to connect to the EL lamp. Electroluminescent Lamp. This is a lamp driver output pin to connect to the EL lamp. Positive Battery Power Supply. Connect such that +2.2V < VDD < +5.0V. Integrating Capacitor. Connecting a fast recovery diode from COIL (pin 3) to this input pin increases the light output of the EL lamp. By connecting a capacitor (0.1F) from this pin to ground, the designer can alter the sawtooth wave output at EL1 and EL2 (pins 4 and 5, respectively) to a square wave output, typically 70VP. Oscillator Resistor. Connecting a 450k resistor to this input pin sets the frequency of the internal clock.
2 3 4 5 6 7
VSS COIL EL1 EL2 VDD CINT
8
ROSC
Rev. 7/16/01
SP4403 Electroluminescent Lamp Driver
(c) Copyright 2001 Sipex Corporation
3
DESCRIPTION The SP4403 contains a DC-AC inverter that can produce an AC output of up to 220VPP from a +2.2V to +5.0V input voltage. An internal block diagram of the SP4403 can be found in Figure 1. The SP4403 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 SP4403 is ideal for applications driving EL lamps to backlight LCD displays, key panels, and other backlit readouts used in battery operated portable equipment. A total of six external components are typically used in standard operation of the SP4403: an inductor, a fast recovery diode, three capacitors and a resistor. A diagram of the SP4403 in a typical application can be found in Figure 2.
VBATT
Electroluminescent Technology An EL lamp is basically a strip of plastic that is coated with a phosphorous material which emits light (fluoresces) when a high voltage (>40V) which was first applied across it, is removed or reversed. Long periods of DC voltages applied to the material tend 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.
SP4403
L1 470H 3 COIL
7 CINT VDD ROSC 450k ROSC 8 OSC fCOIL 6 SCR1 SCR2
D1* 1N4148
CINT* 680pF 100V
C1 1.0F
C2 10nF fLAMP Q FF7 Q fLAMP 1 ELEN EL Lamp *Optional Device 4 VSS EL1 5 EL2
2
Figure 1: Internal Diagram of the SP4403
Rev. 7/16/01 SP4403 Electroluminescent Lamp Driver (c) Copyright 2001 Sipex Corporation
4
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 uniformly light an area without creating any undesirable "hot spots" in the display. THEORY OF OPERATION The SP4403 is a DC-AC inverter made up of: 1. The Oscillator/Frequency Divider, 2. The Coil, and 3. The Switched H-bridge Network. Further details of each element follow. The Oscillator/Frequency Divider The oscillator provides the SP4403 with an onchip clock used to control the coil switch (fCOIL) and the H-bridge network (fLAMP and fLAMP). Although the oscillator frequency can be varied to optimize the lamp output, the ratio of fCOIL/ fLAMP will always equal 128. Figure 1 shows the oscillator output driving the coil and the output of the oscillator with 7 flip flops driving the lamp. The suggested oscillator frequency is 50kHz (Rosc = 450k) for fCOIL. The oscillator output is internally divided down by 7 flip flops to create a second internal control signal at 390Hz for fLAMP. The Coil The supply VBATT can range from +2.2V to +5.0V. VBATT should not exceed the maximum coil current specification. The majority of the current goes through the coil and is typically much greater than IDD. The coil is an external component connected from VBATT to pin 3 of the SP4403. Energy is stored in the coil according to the equation EL=1/2LIP2 where IP, to the first approximation, is the product IP = (tON)((VBATT - VCE)/L), where tON is the time it takes for the coil to reach its peak current, VCE is the voltage drop across the
VBATT
ELEN
1
L1 470H/12
SP4403
VDD ROSC 450k 6 3 COIL D1* 1N4148
ROSC
8
7
CINT
C1* 1.0F
C2 10nF
2 VSS
4 EL1
5 EL2
CINT* 680pF
EL Lamp
*Optional Device
Figure 2: Typical Application Circuit for the SP4403, Set for a Square Wave Output with CINT = 0.1F
internal NPN switch 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 Hbridge 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. For suggested coil suppliers, refer to Page 7. The fCOIL signal controls a switch that connects the end of the coil at pin 3 to ground or to open circuit. The fCOIL signal is a 90% duty cycle signal switching at the oscillator frequency, 50kHz. During the time when the fCOIL signal is HIGH, the coil is connected from VBATT to ground and a charged magnetic field is created in the coil. When the fCOIL 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. fCOIL will send an array of charge pulses (see Figure 4) to the lamp. Each pulse increases the voltage drop across the lamp in discrete steps. As the voltage potential approaches its maximum, the steps become smaller (see Figure 3).
Rev. 7/16/01
SP4403 Electroluminescent Lamp Driver
(c) Copyright 2001 Sipex Corporation
5
The Switched H-Bridge Network The H-bridge consists of two SCR structures that act as high voltage switches. These two switches control the polarity of how the lamp is charged. The SCR switches are controlled by the fLAMP signal which is the oscillator frequency divided by 128. For a 50kHz oscillator, the 7 flip flops will drive fLAMP= 390Hz. When the energy from the coil is released, a high voltage spike is created triggering the SCR switches. The direction of current flow is determined by which SCR is enabled. One full cycle of the H-bridge will create 128 voltage steps from ground to 80V (typical) on EL1 and EL2 (pins 4 and 5, respectively) which are 180 degrees out of phase from each other (see Figure 5). A differential representation of the output is shown in Figure 6. Fine Tuning Performance Circuit performance of the SP4403 can be improved with some of the following suggestions: Increase EL Lamp Light Output: By connecting a fast recovery diode from COIL (pin 3) to CINT (pin 7), 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 Figure 2. Square Wave Output Waveform to the EL Lamp: A 470pF capacitor at CINT (pin13) will act as an integrating capacitor, filtering out any coil switching spikes or ripple in the output waveform to the EL lamp (shown if Figure 1). A designer may change the output waveform to a square wave by using a 0.1F capacitor (shown in Figure 2) at CINT (pin 13).
Printed Circuit Board Layout Suggestions: The SP4403's high-frequency operation makes PC layout important for minimizing ground bounce and noise. Keep the IC's GND pin and the ground leads of C1 and CINT in Figure 2 less than 0.2in (5mm) apart. Also keep the connections to L1 (pin 3) as short as possible. To maximize output power and efficiency and minimize output ripple voltage, use a ground plane and solder the IC's VSS (pin 2) 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, the lamp size, and the inductor used. Sipex supplies characterization charts to aid the designer in selecting the optimum circuit configuration (see Figures 7 to 14). 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 nonbacklit product for a thorough electrical and cosmetic evaluation. Please contact your local Sales Representative for Sipex or the Sipex factory directly to initiate this valued service.
Rev. 7/16/01
SP4403 Electroluminescent Lamp Driver
(c) Copyright 2001 Sipex Corporation
6
Coil Manufacturers
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 Murata 2200 Lake Park Drive, Smyrna Georgia 30080 U.S.A. Phone: (770) 436-1300 Fax: (770) 436-3030 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 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
EL Lamp 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) 4 Lucent Dr. Lebanon, NH. 03766-9004 Phone: (603) 643-7766 Fax: (603) 643-5947 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 Fax: (512) 252-1181
Polarizers/transflector Mnfg.
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
Rev. 7/16/01
SP4403 Electroluminescent Lamp Driver
(c) Copyright 2001 Sipex Corporation
7
VPEAK=80V (typical)
EL1 output; 64 charge steps per half cycle
Figure 3. EL Output Voltage in Discrete Steps at EL1 Output
64 coil pulses per half cycle; 89% duty cycle.
Figure 4. Voltage Pulses Released from the Coil to the EL Driver Circuitry
EL1 Output
EL2 Output
Figure 5. EL Voltage Waveforms from the EL1 and EL2 Outputs
EL1 Output VPP=160V (typical) EL2 Output
Differential Representation E12.
Figure 6. EL Differential Output Waveform of the EL1 and EL2 Outputs
Rev. 7/16/01 SP4403 Electroluminescent Lamp Driver (c) Copyright 2001 Sipex Corporation
8
The following performance curves are intended to give the designer a relative scale from which to optimize specific applications. Absolute measurements may vary depending upon the brand of components chosen.
OSCL1: FREQUENCY VS. RESISTANCE, VDD=3.0V 600
500
FREQUENCY (KHz)
400
300
200
100
0 49.9
102.0
200.0
301.0
402.0
499.0
604.0
715.0
806.0
909.0
1000.0
RESISTANCE (K)
Figure 7: Oscillator Frequency vs ROSC, VDD=3.0V
SUPPLY CURRENT VS. Rosc, VDD=3.0V, L=470uH (4.9OHMS), LAMP=6.8nF 60
50
SUPPLY CURRENT (mA)
40
30
20
10
0 200 301 402 511 Rosc (K) 604 715 806
Figure 8: ITOTAL vs ROSC, VDD=3.0V, Coil=470H, 4.9
Rev. 7/16/01
SP4403 Electroluminescent Lamp Driver
(c) Copyright 2001 Sipex Corporation
9
OUTPUT VOLTAGE VS. Rosc, VDD=3.0V, L=470uH (4.9 OHMS), LAMP=6.8nF 250.0
200.0
OUTPUT VOLTAGE (VPK-PK)
150.0
100.0
50.0
0.0 200 301 402 511 Rosc (K) 604 715 806
Figure 9: Output Voltage vs ROSC, VDD=3.0V, Coil=470H, 4.9
OUTPUT VOLTAGE VS. LAMP SIZE, VDD=3V, L=470uH (4.9OHMS) 200.0 180.0 160.0
OUTPUT VOLTAGE (VPK-PK)
140.0 120.0 100.0 80.0 60.0 40.0 20.0 0.0 1.5 2.0 2.5 3.0 LAMP SIZE (SQ-IN) 3.5 4.0 5.0
Figure 10: Output Voltage vs Lamp Size, VDD=3.0V, ROSC=450k, Coil=470H, 4.9
Rev. 7/16/01
SP4403 Electroluminescent Lamp Driver
(c) Copyright 2001 Sipex Corporation
10
BRIGHTNESS VS. Rosc, VDD=3.0V, L=470uH (4.9 OHMS), LAMP=6.8nF 7
6
BRIGHTNESS (FtLm)
5
4
3
2
1
0 200
301
402
511 Rosc (K)
604
715
806
Figure 11: Luminance vs ROSC, VDD=3.0V, Coil=470H, 4.9
BRIGHTNESS VS. LAMP SIZE, VDD=3V, L=470uH (4.9OHMS) 8.00 7.00 6.00
BRIGHTNESS (Ft-Lm)
5.00 4.00 3.00 2.00 1.00 0.00 1.5 2.0 2.5 3.0 LAMP SIZE (SQ-IN) 3.5 4.0 5.0
Figure 12: Luminance vs Lamp Size, VDD=3.0V, ROSC=450k, Coil=470H, 4.9
Rev. 7/16/01
SP4403 Electroluminescent Lamp Driver
(c) Copyright 2001 Sipex Corporation
11
SUPPLY CURRENT VS. LAMP SIZE, VDD=3V, L=470uH (4.9OHMS) 35
30
SUPPLY CURRENT (mA)
25
20
15
10
5
0 1.5 2.0 2.5 3.0 LAMP SIZE (SQ-IN) 3.5 4.0 5.0
Figure 13: ITOTAL vs Lamp Size, VDD=3.0V, ROSC=450k, Coil=470H, 4.9
Rev. 7/16/01
SP4403 Electroluminescent Lamp Driver
(c) Copyright 2001 Sipex Corporation
12
All package dimensions in inches
8-pin MSOP
0.0256 BSC 0.012 0.003 0.0965 0.003 0.118 0.004 R .003 0.16 0.003 12.0 4 0.01 1 2 12.0 4 0.008 0 - 6 0.006 0.006 0.006 0.006
0.020 0.020
0.0215 0.006 0.037 Ref
3.0 3
0.116 0.004
0.034 0.004 0.040 0.003 0.116 0.004
0.013 0.005 0.118 0.004
0.004 0.002
0.118 0.004
50 MSOP devices per tube
P
1 2 3 4
8 7 6 5
1 2 3 4
8 7 6 5
1 2 3 4
8 7 6 5
1 2 3 4
8 7 6 5
W
8-pin MSOP 13" reels: P = 8mm, W = 12mm Package EU minimum quantity per reel 500 standard quantity per reel 2500
Rev. 7/16/01
SP4403 Electroluminescent Lamp Driver
(c) Copyright 2001 Sipex Corporation
13
ORDERING INFORMATION
Model Temperature Range Package Type SP4403EU .............................................. -40C to +85C .......................................... 8-Pin MSOP SP4403UEB ........................................................................................................ Evaluation Board
Corporation
SIGNAL PROCESSING EXCELLENCE
Sipex Corporation
Headquarters and Sales Office 22 Linnell Circle Billerica, MA 01821 TEL: (978) 667-8700 FAX: (978) 670-9001 e-mail: sales@sipex.com 233 South Hillview Dr Milpitas, CA 95053 TEL: (408) 934-7500 FAX: (408) 935-7600
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.
Rev. 7/16/01
SP4403 Electroluminescent Lamp Driver
(c) Copyright 2001 Sipex Corporation
14

▲Up To Search▲

Price & Availability of SP4403

	To Download SP4403 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .