9-47; Rev 0; /07 MAX4990 Evaluation Kit General Description The MAX4990 evaluation kit (EV kit) provides a proven design to evaluate the MAX4990 high-voltage, ±5kV ESD-protected electroluminescent lamp driver. Alligator clip leads contact a wide variety of standard electroluminescent lamps. The MAX4990 EV kit printed-circuit board (PCB) comes with a MAX4990ETD+ installed. Ordering Information PART TYPE MAX4990EVKIT+ EV Kit +Denotes lead-free and RoHS-compliant. DESIGNATION QTY DESCRIPTION C, C5 C C C4 C6 C7 C8 µf ±0%, 5V X5R ceramic capacitors (060) Murata GRM88R6E05K 000pF ±0%, 5V C0G ceramic capacitor (060) Murata GRM885CE0J 68pF ±5%, 50V C0G ceramic capacitor (060) Murata GRM885CH680J 0.µF ±0%, 6V X7R ceramic capacitor (060) Murata GRM88R7C04K 00pF ±0%, 50V X5R ceramic capacitor (0805) TDK C0X7REM 5000pF ±0%, 50V X7R ceramic capacitor (060) Murata GRM88R7H5K 0µF ±0%, 5V X5R ceramic capacitor (06) Murata GRMCR6E06K D S i l i con d i od e ( S OT) ( Top M ar k: A8) Central Semiconductor CMPD00 LEAD FREE JU, JU -pin headers JU, JU4 JU8 6 -pin headers L 0µH inductor (.8mm x.8mm) TOKO DC00BS-M Features Lead-Free and RoHS-Compliant Proven PCB Layout Fully Assembled and Tested Alligator Clips Contact Wide Range of EL Displays Single 5V Supply or Split Battery/Digital Supplies Fixed or Adjustable Output Slew Rate, Brightness, Soft On/Soft Off Fixed or Adjustable f EL and f SW Component List DESIGNATION QTY DESCRIPTION R 00kΩ ±5% resistor (060) R, R4 74kΩ ±% resistors (060) R MΩ ±5% resistor (060) R5.kΩ ±% resistor (060) R6 40.kΩ ±% resistor (060) R7 4kΩ ±% resistor (060) U U VA, VB VC VR, VR High-voltage EL panel driver (4-pin, mm x mm TDFN) Maxim MAX4990ETD+ (Top Mark: ADL) M axi m d ual C M OS ti m er ICM7556ISD+ ( 4- p i n S O ) Alligator clip/banana connectors, red boot 7pF to 50pF variable capacitor (4mm x 4.5mm) Murata TZB4R500BA0R00 M Ω top - ad j ust, - tur n tr i m m er s ( m m ) Murata PV7W05C0B00 VR 500kΩ top - adj ust, - tur n tr i m m er ( m m ) Murata PV7W504C0B00 8 Shunts Wires (VA, VB) PCB: MAX4990 Evaluation Kit+ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim Direct at -888-69-464, or visit Maxim s website at www.maxim-ic.com.
Quick Start Recommended Equipment Before beginning, the following equipment is needed: MAX4990 EV kit A user-supplied electroluminescent (EL) lamp 5V DC power supply Oscilloscope to monitor VA and VB Component Suppliers SUPPLIER PHONE WEBSITE Central Semiconductor Corp. 6-45-0 www.centralsemi.com Murata Mfg. Co., Ltd. 770-46-00 www.murata.com TDK Corp. 847-80-600 www.component.tdk.com TOKO America, Inc. 847-97-0070 www.tokoam.com Note: Indicate that you are using the MAX4990 when contacting these component suppliers. Procedure The MAX4990 EV kit is fully assembled and tested. Follow the steps below to verify board operation: ) Verify that all jumpers (JU JU8) are in their default positions, as shown in Table. ) Connect the VA and VB alligator clip leads to the EL lamp. Note: Under some conditions, the VA/VB output may be as high as 50V P-P. ) Connect the oscilloscope to VA and VB. With math function, monitor VA-VB waveform. 4) Connect the 5V DC power supply between the VDD and pins. 5) Switch on the 5V power supply. Verify that the EL lamp illuminates. Table. MAX4990 EV Kit Jumper Descriptions (JU JU8) JUMPER SIGNAL SHUNT POSITION FUNCTION JU JU JU JU4 JU5 JU6 JU7 JU8 SLEW EN DIM EL SW VDD VDD VBATT -* Set by R - Adjustable by VR -* EN = logic-high: normal operation Open EN = logic-low: shutdown - Adjustable by VR -* Set by R4 - Adjustable by VR Open* Set by C - Adjustable by VC Open* -* Open -* Open -* Open Set by C Power supplied to U by VDD Note: VDD must be 5V U must be powered independently Power supplied to U by VDD Note: VDD must be 5V U must be powered independently VDD and VBATT connected together Note: VBATT must be 5V VBATT supplies L independent of VDD *Default position.
Detailed Description of Hardware The MAX4990 EV kit provides a proven layout for the MAX4990. Component selection, adjustment range, and typical operation values for a typical EL panel (.5in x.5in area, nominal 5nF load capacitance) are described in the sections that follow. Slew Rate (R SLEW ) Slew rate is set by the resistance on the SLEW pin (see Table ). Many other adjustments depend upon the slew rate setting as a reference. The equation is: V 5 Slew Rate M 00µ s =. ( R Ω ) SLEW The VR + R resistance can be adjusted to a specific value before applying power, by connecting an ohmmeter between JU pin and. After adjusting VR to the desired value, disconnect the ohmmeter, install the JU shunt, and finally, apply power to the EV kit. Table. Output Voltage Configuration Output Voltage (R DIM, R SLEW ) The output voltage control interacts with the slew rate control (see Table ). Peak-to-peak output voltage is set by the ratio of the resistances on the DIM and SLEW pins: R V DIM P P= 00, subject to the constra int 70V VP P 50V RSLEW The VR resistance can be adjusted to a specific value before applying power, by connecting an ohmmeter between JU pin and. After adjusting VR to the desired value, disconnect the ohmmeter, install the JU shunt, and finally, apply power to the EV kit. Table. Slew Rate Configuration JU SHUNT POSITION VR TRIMMER R SLEW SLEW RATE (V/00µs) - R = 0.74 0-5% CW 50% CW VR + R = 0.560 VR + R = 0.997 CW = Clockwise. Approximate trimmer values provided for initial guidance only. 0 JU SHUNT POSITION VR TRIMMER R SLEW JU SHUNT POSITION VR TRIMMER R DIM V P-P (V) - R4 = 0.74 00 - R = 0.74 7% CW VR = 0.5 90 - % CW VR = 0.7 50 9% CW VR = 0.86 00 - R4 = 0.74 44 5% CW VR + R = 0% CW VR = 0. 80 0.560-5% CW VR = 0.496 8-6% CW VR = 0.79 4 - R4 = 0.74 86 50% CW VR + R = 9% CW VR = 0.8 86 0.997-5% CW VR = 0.700 50 70% CW VR =.98 60
Soft-Start (R DIM, C DIM ) Subject to the constraint that R DIM /R SLEW., the gradual turn-on/turn-off time is set by R DIM and C DIM (see Table 4) by the equations: ton = 6. RDIM CDIM toff =. RDIM CDIM Table 4. Soft-Start Configuration C DIM (µf) C =.0 JU SHUNT POSITION VR TRIMMER Lamp Output Frequency (R SLEW, C EL ) Lamp output frequency can be set by an external capacitor, C EL (see Table 5): R DIM 0. 087 fel = RSLEW CEL - R4 = 0.74 0.97 0.449 - t ON (S) t OFF (S) 7% CW VR = 0.5 0.95 0.8 0% CW VR = 0. 0.549 0.5 8% CW VR = 0.74 0.97 0.449 5% CW VR = 0.496.90 0.595 5% CW VR = 0.700.80 0.840 50% CW VR =.000.600.00 70% CW VR =.98.65.678 Table 5. Lamp Output Frequency When JU4 = Open (Internal f EL ) C EL (pf) JU SHUNT POSITION VR TRIMMER C = 560 C = 000 R SLEW f EL (Hz) - R = 0.74 90-5% CW VR + R = 0.560 60 50% CW VR + R = 0.997 50 - R = 0.74 8-5% CW VR + R = 0.560 46 50% CW VR + R = 0.997 8 4
Lamp Output Frequency (External f EL Signal) When the f EL pin is driven by an external clock, the lamp frequency is f EL /4. The EV kit uses an ICM7556 dual CMOS timer (U) to generate a 50% duty-cycle square wave. The VR value can be adjusted while power is applied (see Table 6). Boost Converter Frequency (R SLEW, C SW ) ICM7556 square-wave frequency f EL = /(.4 x R x C). The boost converter switching frequency can be set by an external capacitor, C SW (see Table 7). 6. fsw = RSLEW CSW Boost Converter Frequency (External f SW Signal) Boost converter switching frequency can be driven by an external clock. The EV kit uses an ICM7556 dual CMOS timer (U) to generate a 90% duty-cycle squarewave pulse. The C SW value can be adjusted while power is applied (see Table 8). Table 6. Lamp Output Frequency When JU4 = Pins - (External f EL ) ICM7556 T IM IN G C A PAC IT OR ( p F ) VR TRIMMER ICM7556 TIMING RESISTORS (kω) f EL FROM ICM7556 (khz) LAMP FREQUENCY = f EL /4 (Hz) 0% CW VR + R5 = 5. 0.097 C7 = 5000 50% CW VR + R5 = 6. 0.80 45 00% CW VR + R5 =..58 895 Table 7. Boost Converter Frequency When JU5 = Open (Internal f SW ) C SW (pf) JU SHUNT POSITION VR TRIMMER C = 68 R SLEW f SW (khz) - R = 0.74 4-5% CW VR + R = 0.560 95 50% CW VR + R = 0.997 5 Table 8. Boost Converter Frequency When JU5 = Pins - (External f SW ) VC TRIMMER ICM7556 TIMING CAPACITOR (pf) f SW = ICM7556 SQUARE WAVE =.44/((R7 + x R6) x (VC)) (khz) Minimum: 0 VC = 7 + 5 Center: 90 or 70 VC = 0 + 5 60 Maximum: 80 (50 VC 00) + 5 Note: fsw square wave has fixed duty cycle = (R6 + R7)/(R7 + x R6) = 90%. Approximate trimmer values provided for initial guidance only. 5
VDD VR MΩ R4 74kΩ % R MΩ JU JU C µf 5V FEL FEL FSW FSW VR MΩ R 74kΩ % JU4 R 00kΩ C 000pF 5V JU5 C 68pF 50V JU 4 5 6 7 SLEW EN DIM EL SW V DD U MAX4990 V A 4 N.C. V B N.C. CS 0 9 N.C. LX 8 VA HIGH VOLTAGE (60V DC MAX) VB HIGH VOLTAGE (60V DC MAX) CS HIGH VOLTAGE (60V DC MAX) NOTES: f SW FREQUENCY RANGE = 0kHz TO 0kHz f EL FREQUENCY RANGE = 0.kHz TO.6kHz LAMP FREQUENCY = f EL/4 = 5Hz TO 900Hz VDD VBATT VBATT VDD VDD C4 0.µF 6V C8 0µF 5V C5 µf 5V JU6 JU7 JU8 C6 00pF 50V L 0µH HIGH VOLTAGE (60V DC MAX) CS D VDD VDD VBATT FEL R5.kΩ % VR 500kΩ 4 5 6 7 DISCHARGE THRESHLD CTRLVOLT RESET OUT TRIGGER U ICM7556 V+ 4 DISCHARGE THRESHLD CTRLVOLT RESET 0 OUTPUT 9 TRIGGER 8 FSW VDD R7 4kΩ % R6 40.kΩ % C7 5000pF 50V VC 7pF TO 50pF Figure. MAX4990 EV Kit Schematic 6
Figure. MAX4990 EV Kit Component Placement Guide Component Side Figure. MAX4990 EV Kit PCB Layout Component Side 7
Figure 4. MAX4990 EV Kit PCB Layout Solder Side Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 8 Maxim Integrated Products, 0 San Gabriel Drive, Sunnyvale, CA 94086 408-77-7600 007 Maxim Integrated Products is a registered trademark of Maxim Integrated Products, Inc.