19-2214; Rev 0; 10/01 MAX1895 Evaluation Systems Note: Windows NT/2000 requires additional driver software; contact the factory. To evaluate the performance of the MAX1995, configure the MAX1895EVSYS for analog interface mode. There is no need to change the IC since the MAX1895’s performance is identical to the MAX1995’s performance. See Detailed Description of Hardware, Table 2 and Table 3. Component Suppliers SUPPLIER PHONE FAX Diodes Inc. 805-446-4800 805-446-4850 Fairchild 888-522-5372 972-910-8036 General Semiconductor 760-804-9258 760-804-9259 International Rectifier 310-322-3331 310-252-7175 Murata 770-436-1300 770-436-3030 Sumida 847-956-0666 847-956-0702 Taiyo Yuden 800-348-2496 847-925-0899 TDK 847-803-6100 847-390-4405 Toko 847-297-0070 847-699-1194 Toshiba 949-455-2000 949-859-3963 Features ♦ Single Lamp Application (MAX1895EVSYS-S) Dual Lamp Application (MAX1895EVSYS-D) ♦ 7V to 24V Input Range ♦ Wide Brightness Adjustment Range ♦ Open Lamp Protection with 2s Timeout ♦ Brightness Adjustable through SMBus Interface or On-Board Potentiometer ♦ No Flicker at Low Brightness ♦ High Power-to-Light Efficiency ♦ I2C/SMBus Compatible ♦ Easy to Use Menu-Driven Software ♦ Assembled and Tested ♦ Includes: Windows 95/98-Compatible Software (3.5in Floppy Disk) and Demo PC Board Ordering Information PART SMBus is a trademark of Intel Corp. Windows is a registered trademark of Microsoft Corp. I2C is a trademark of Philips Corp. NUMBER OF LAMPS MAX1895EVSYS-S 0°C to +70°C 1 MAX1895EVSYS-D 0°C to +70°C 2 MAX1895EVSYS-S Component List PART Note: Please indicate you are using the MAX1895 when contacting these manufacturers. TEMP RANGE QTY DESCRIPTION MAX1895EVKIT-S 1 MAX1895 evaluation kit (for single-lamp application) MAXSMBUS 1 Interface board MAX1895EVSYS-D Component List PART QTY DESCRIPTION MAX1895EVKIT-D 1 MAX1895 evaluation kit (for dual-lamp application) MAXSMBUS 1 Interface board ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. 1 Evaluate: MAX1895/MAX1995 General Description The MAX1895 evaluation systems are assembled and tested PC boards that demonstrate the MAX1895 highefficiency, wide brightness range CCFL backlight controller. The MAX1895EVSYS-S is designed for singlelamp applications and the MAX1895EVSYS-D is designed for dual-lamp applications. Both systems can control the brightness of the lamps through either the SMBus interface or by an on-board potentiometer. The systems include a Maxim SMBus™ interface board (MAXSMBUS), which allows an IBM-compatible PC to use its parallel port to emulate an Intel system management bus (SMBus) I2C™ interface. Windows 95/98®compatible software provides a user-friendly interface to exercise the features of the MAX1895. The program is menu-driven and offers a graphic interface with control buttons and status display. Evaluate: MAX1895/MAX1995 MAX1895 Evaluation Systems MAX1895EVKIT Component List DESIGNATION C1, C13, C14, C17 DESCRIPTION J1 1 2 ✕ 10 right angle female receptacle 100pF, 50V, NPO ceramic capacitor JU1, JU8 0 Not installed JU2, JU3 2 4-pin headers ‘T’ 1 0.01µF, 16V, X7R ceramic capacitor JU4, JU6, JU7 3 3-pin headers JU5 1 2-pin header 1 0.022µF, 16V, X7R ceramic capacitor See Table 4 C2, C4, C6, C9, C10 5 C3 1 C11 C12 DESCRIPTION 1 0.1µF, 10V, X5R ceramic capacitors Murata GRP155R61A104K Taiyo Yuden LMK105BJ104MV TDK C1005X5R1A104K C8 QTY D3 See Table 4 C7 DESIGNATION Diode, 1N4148-type Fairchild MMSD4148 General Semiconductor 1N4148W Diodes Incorporated 1N4148W 4 C5 1 1 0 15pF, 3.1kV, ceramic highvoltage capacitor Murata GRM42D1X3F150J TDK C4520C0G3F150K 1µF, 25V, X7R ceramic capacitor Murata GRM31MR71E105K Taiyo Yuden TMK316BJ105KL TDK C3216X7R1E105K Not installed (Use two 0.47µF, 25V capacitors for C11 and C12 to lower ESR and increase efficiency) M1 1 N1A/B, N2A/B 2 See Table 4 R1 1 100kΩ ±1% resistor R2, R8 0 Not installed R3 1 100kΩ ±1% resistor R4 1 49.9kΩ ±1% resistor R5, R6, R9, R10 4 10kΩ ±5% resistors 10kΩ potentiometer (multiturn) R7 1 R11 1 150Ω ±1% resistor (0603) R12 2 2kΩ ±5% resistor (0603) R13–R17 5 See Table 4 1 Transformer 93:1 Toko T912MG-1018 (BLC103B style) 0.1µF, 25V, X7R ceramic capacitor TDK C1608X7R1E104K T1 1 T2 1 See Table 4 U1 1 MAX1895EGI C16 1 0.47µF, 10V, X5R ceramic capacitor Taiyo Yuden LMK107BJ474KA TDK C1µ608X5R1A474K None 5 Shunts for JU2 (1-3), JU3 (1-4), JU4 (1-2), JU6 (1-2), JU7 (1-2) C18 1 0.01µF, 50V, X7R ceramic capacitor D1, D4, D5, D6 4 See Table 4 1 100mA dual Schottky diode— common anode Diodes Incorporated BAT54AW Central Semiconductor CMSSH-3A C15 D2 2 QTY _______________________________________________________________________________________ MAX1895 Evaluation Systems Required Equipment Before you begin you will need the following equipment: • An IBM PC-compatible computer running Windows 95/98 • A parallel printer port (this is a 25-pin socket on the back of the computer) • A standard 25-pin, straight-through, male-to-female cable to connect the computer’s parallel port to the Maxim SMBus interface board • A DC power supply capable of supplying any voltage between 7V to 20V at 100mA to power the SMBus board • A DC power supply capable of supplying a voltage between 7V to 24V at 2A to power the MAX1895 board • A CCFL lamp with the following specifications: Lamp Current ≤ 6mA Note: Analog interface operation requires only a power supply (between 7V to 24V at 2A) and a CCFL lamp. WARNING! High voltages are present on this evaluation kit. Use caution when making connections and applying power. Procedure 1) Carefully connect the boards by aligning the 20-pin connector of the MAX1895 EV kit with the 20-pin header of the MAXSMBUS interface board. Gently press them together. The two boards should be flush against each other. 2) Do not turn on the power until all connections are made. 3) Connect the lamp to the high-voltage pads. 4) Set the jumpers to the following position: Open 1-3 JU3 1-4 JU4 1-2 JU5 Open JU6 1-2 JU7 1-2 7) Connect a 7V to 20V DC power supply to the pads labeled POS9 and GND1 of the SMBus interface board. 9) Turn on both power supplies. Input Power ≤ 4W JU2 6) The MAX1895.EXE software program can be run from the floppy or hard drive. Simply use the Windows program manager to run the program. If desired, you may use the INSTALL.EXE program to copy the files and create icons for them in the Windows 95/98 Start Menu. An uninstall program is included with the software. Simply click on the UNINSTALL icon to remove the EV kit software from the hard drive. 8) Connect the 12V supply to the pads labeled VIN and GND. Maximum Strike Voltage ≤ 1.2kV JU1 5) Connect a cable from the computer’s parallel port to the SMBus interface board. Use a straightthrough 25-pin female-to-male cable. To avoid damaging the EV kit or your computer, do not use a 25pin SCSI port or any other connector that is physically similar to the 25-pin parallel printer port. 10) Start the MAX1895 program by opening its icon in the Start Menu. 11) Observe as the program automatically detects the address of the MAX1895 and starts the main program. Detailed Description of Software User-Interface Panel The user interface is easy to operate using the mouse, or by using the tab key to navigate with the arrow keys. Each of the buttons corresponds to bits in the command and configuration bytes. Clicking on them generates the correct SMBus write operation to update the internal registers. The brightness of the lamp can be adjusted by either moving the trackbar or by entering a value between 0 and 31 into the edit field located below the trackbar. Pressing enter after typing in the new value updates the internal register. The SHMD register configures the operation of the device as described in Table 1. When the Automatic Read feature is enabled, the program polls the MAX1895 twice a second. The brightness, mode, and status are read and the appropriate fields are updated on the main display. Unchecking the checkbox can disable this feature and each field can be updated individually by clicking the appropriate button. _______________________________________________________________________________________ 3 Evaluate: MAX1895/MAX1995 Quick Start Evaluate: MAX1895/MAX1995 MAX1895 Evaluation Systems The Brightness Cycle feature cycles the brightness through its entire range. The Status register indicates whether the lamp circuit has opened (Status1 low) or an overcurrent condition has occurred (Status0 low). The RESET button will set the MAX1895 and software to the POR state. If in doubt, click the reset button. Simple SMBus Commands There are two methods for communicating with the MAX1895: through the normal user-interface panel, or through the SMBus commands available from pressing the MAXSMBUS button. A display pops up that allows the SMBus protocols, such as Read Byte and Write Byte, to be executed. To stop normal user-interface execution so that it does not override the manually set values, turn off the timer by unchecking the Automatic Read checkbox. The SMBus dialog boxes accept numeric data in binary, decimal, or hexadecimal. Hexadecimal numbers should be prefixed by $ or 0x. Binary numbers must be exactly 8 digits. Detailed Description of Hardware Jumper JU1 Jumper JU1 connects the current limit pin (ILIM) to VCC. With the shunt installed, the current limit is set to: formed by R1 and R2. Use the equation shown below to calculate the current limit: R2 2V × 1 R 1 + R2 Current Limit (A) = × 5 RDS(ON) of N1 The MAX1895 EV kit (single lamp) is shipped with R1 = 100kΩ, R2 open, and RDS(ON)-TYPICAL = 0.113Ω. The dual lamp has an RDS(ON)-TYPICAL = 0.044Ω. Jumper JU2 Jumper JU2 sets the voltage on the MINDAC pin. This voltage sets the DAC’s minimum scale output voltage, which sets the lamp brightness for the minimum DAC code. In the 1-2 position, MINDAC is connected to VCC. In this position, the lamp is completely off at the minimum scale. Additionally, the DPWM dimming function is disabled (refer to the MAX1895 data sheet). In the 1-3 position, MINDAC is connected to REF through a voltage-divider formed by R3 and R4. The voltage on MINDAC is approximately 0.67, allowing a minimum analog dimming range of 33% of maximum brightness. The DPWM dimming function still remains available. In the 1-4 position, MINDAC is connected directly to REF. The voltage on MINDAC is 2V effectively disabling analog dimming. Only DPWM dimming is available. Jumper JU3 0.2V RDS(ON) of N1 With the shunt removed, the current limit is determined by the RDS(ON) of MOSFET N1 and the resistor-divider Jumper JU3 sets the MAX1895 to either analog interface or SMBus interface. There are two possible settings in analog interface: negative scale and positive scale. In negative-scale analog interface (JU3 = 1-2), the brightness of the lamp decreases as the voltage on Table 1. SH/SUS and SHMD Register Truth Table 4 SH/SUS 0 SHMD2 0 SHMD1 X 0 0 X 1 Shutdown STATUS1 set 1 0 0 X Operate SHMD0 0 OPERATING MODE Operate 1 0 1 X Shutdown STATUS1 set X 1 X X Shutdown STATUS1 set _______________________________________________________________________________________ MAX1895 Evaluation Systems Jumper JU4 Jumper JU4 connects the CRF/SDA pin to VCC either directly (position 2-3) or through a 10kΩ resistor (position 1-2). Position 1-2 is for SMBus operation. A 10kΩ pullup resistor is connected to the SMBus data signal. To use the analog interface, connect JU4 to position 2-3. The CRF/SDA pin sets the full brightness reference for the CTL/SCL pin. Connecting this pin directly to VCC sets the full brightness reference voltage to 5.3V. To use a voltage other than 5.3V, leave JU4 open and apply an external voltage to the pad CRF/SDA. Jumpers JU5 and JU6 The jumper JU5 must be left open for SMBus operation to prevent loading to the SMBus data signal. Jumper JU6, position 1-2, is for SMBus operation. A 10kΩ pullup resistor is connected to the SMBus clock signal. To use analog interface, install a shunt on JU5. This connects potentiometer R8 to the CRF/SDA pin voltage. When using this mode, jumper JU6 must be installed in the 2-3 position. This connects the wiper of R8 to the CTL/SCL pin. Adjusting R8 changes the voltage on this pin, which changes the brightness of the lamp. Jumper JU7 Jumper JU7, position 1-2, enables the MAX1895 unless the SMBus suspend line (SH/SUS) pulls low. In the 2-3 position, the MAX1895 is placed into shutdown mode. Jumper JU8 Jumper JU8 connects the power-supply input for the gate drivers (VDD), to the 5.3V linear regulator output (VCC). To use a different voltage for the gate drivers, cut the trace shorting jumper JU8 and apply the desired voltage to the pad labeled VDD. Table 2. Jumper Settings Description JUMPER SHUNT LOCATION Open* JU1 JU3 0.2V RDS(ON) of N1 Note: Remove R1 before installing the shunt. 1-2 MINDAC = VCC: disables the DPWM chopping function. 1-3* MINDAC ≅ 0.67V: MINDAC is connected to REF through a voltage-divider formed by R3 and R4. This voltage sets the DAC’s minimum scale output voltage. 1-4 MINDAC = 2V: MINDAC is connected to REF. Analog dimming is disabled. 1-2 MODE = REF: (negative-scale analog interface), CTL/SCL = 0V results in maximum brightness. 1-3 MODE = GND: (positive-scale analog interface), CTL/SCL = 0V results in minimum brightness. 1-4* MODE = VCC: enable SMBus interface. Open JU4 Current limit is set by the resistor-divider formed by R1 and R2. (The MAX1895 EV kit is shipped with R1 = 100kΩ and R2 open.) Current limit is set to: Closed JU2 FUNCTION Used for analog interface: drive CRF/SDA with an external voltage. The external voltage is the reference voltage. (JU3 must be in 1-2 or 1-3 position. JU5 = closed.) 1-2* Used for SMBus interface: CRF/SDA connected to VCC through 10kΩ pullup resistor. 2-3 Used for analog interface: CRF/SDA = VCC. VCC is the full-brightness reference input voltage. (JU3 must be in 1-2 or 1-3 position. JU5 = closed.) *Default position. _______________________________________________________________________________________ 5 Evaluate: MAX1895/MAX1995 pin CTL/SCL increases. In positive-scale ADC interface (JU3 = 1-3), the brightness of the lamp increases as the voltage on pin CTL/SCL increases. Jumper (JU3 = 1-4) enables the SMBus interface on the MAX1895. Refer to the MAX1895 data sheet for more information. Evaluate: MAX1895/MAX1995 MAX1895 Evaluation Systems Table 2. Jumper Settings Description (continued) JUMPER JU5 JU6 JU7 JU8 SHUNT LOCATION FUNCTION Open* Used for SMBus interface: drive CRF/SDA with SMBus data. Closed Used for analog interface: drive CRF/SDA with analog voltage. (Connect JU2 to 1-2 position to use VCC as the analog voltage.) 1-2* Used for SMBus interface: CTL/SCL connected to VCC through 10kΩ pullup resistor. 2-3 Used for analog interface: CTL/SCL connected to ADC reference input voltage (CRF/SDA) through potentiometer R8. Adjusting R8 changes the brightness. 1-2* Used for SMBus mode: SH/SUS is connected to VCC through 10kΩ pullup resistor. 2-3 Places the MAX1895 into shutdown. Open Drive VDD (power supply for the gate drivers) with an external power supply. Closed* VDD is tied to VCC (pin 28, 5.3V linear regulator output). *Default position Table 3. Jumper Settings Quick Reference 6 JUMPER SMBUS DIGITAL INTERFACE ANALOG INTERFACE JU1 Open Open JU2 1-3 1-3 JU3 1-4 1-2 or 1-3 JU4 1-2 2-3 JU5 Open Closed JU6 1-2 2-3 JU7 1-2 1-2 JU8 Closed Closed _______________________________________________________________________________________ MAX1895 Evaluation Systems Evaluate: MAX1895/MAX1995 Table 4. Components Different Between the Single-Lamp and Dual-Lamp Boards DESIGNATION C1 MAX1895EVKIT-S (SINGLE LAMP) QTY 1 DESCRIPTION 4.7µF, 25V ceramic capacitor Taiyo Yuden TMK325BJ475MN TDK C3225X7R1E475M MAX1895EVKIT-D (DUAL LAMP) QTY DESCRIPTION 1 10µF, 25V ceramic capacitor Taiyo Yuden TMK432BJ106MM TDK C4532X7R1E106M C13 0 Not installed 1 0.1µF, 16V ceramic capacitor Murata GRM188R71C104K Taiyo Yuden EMK107BJ104KA TDK C1608X7R1C104K C14 0 Not installed 1 15pF, 3kV high-voltage ceramic capacitor Murata GRM42D1X3F150J TDK C4520C0G3F150K 1 0.022µF, 16V ceramic capacitor Murata GRP155R71C223K Taiyo Yuden EMK105BJ223KV TDK C1005X7R1E223K 1 6.2V zener diode Central Semiconductor CMPZ5234B Diodes Inc. BZX84C6V2 Fairchild Semiconductor MMBZ5234B C17 D1 0 Not installed 1 1N4148-type diode Diodes Inc. MMBD4148 Fairchild Semiconductor MMBD4148 General Semiconductor IMBD4148 D4 0 Not installed 1 D5 0 Not installed 1 D6 0 Not installed 1 6.2V zener diode Central Semiconductor CMPZ5234B Diodes Inc. BZX84C6V2 Fairchild Semiconductor MMBZ5234B 1N4148-type diode Diodes Inc. 1N4148W Fairchild Semiconductor MMSD4148 General Semiconductor 1N4148W Dual Schottky common-cathode diode Central Semiconductor CMPSH-3C Diodes Inc. BAT54C Fairchild Semiconductor BAT54C General Semiconductor BAT54C M1 0 Not installed 1 2N7002 MOSFET Central Semiconductor 2N7002 Diodes Inc. 2N7002 General Semiconductor 2N7002 N1, N2 2 Dual N-channel MOSFETs Fairchild Semiconductor FDC6561AN 2 Dual N-channel MOSFETs Fairchild Semiconductor FDS6930A R13 0 Not installed 1 4.7kΩ ±5% resistor R14 0 Not installed 1 20kΩ ±5% resistor R15 0 Not installed 1 2kΩ ±5% resistor R16, R17 2 0Ω resistors 0 Not installed T2 0 Not installed 1 Transformer 93:1 Toko T912MG-1018 (BLC103B Style) _______________________________________________________________________________________ 7 Evaluate: MAX1895/MAX1995 MAX1895 Evaluation Systems Figure 1. Main Display for MAX1895EVKIT 8 _______________________________________________________________________________________ SMBDATA JU5 R8 SHORT PC TRACE R7 10kΩ CRF/SDA REF 3 2 4 1 VCC 2 4 CTL/SCL JU6 1 1 REF MODE 3 3 2 JU4 1 VCC VCC 3 2 JU3 R3 R4 49.9kΩ 100kΩ 1% 1% REF R6 10kΩ VCC C3 100pF REF JU1 SMBCLK R9 10kΩ R5 10kΩ JU2 R2 OPEN R1 100kΩ 1% REF GND CTL/SCL CRF/SDA MODE GND MINDAC REF ILIM SMBSUS R10 10kΩ 7 6 5 4 3 C2 0.1µF 2 1 28 VCC VCC C16 0.47µF 3 SH/SUS JU7 1 2 SH/SUS 8 27 BATT C15 0.1µF N.C. 9 U1 N.C. 10 JU8 N.C. 11 MAX1895 26 CCV VCC C5 0.01µF VDD 24 IFB C4 0.1µF C6 0.1µF VDD 12 25 CCI IFB R16* 3 PGND 13 23 N.C. GL2 14 22 VFB GL1 GH1 LX1 BST1 BST2 LX2 GH2 2 R L 1 15 16 17 18 19 20 21 GL2 R14* D6* C10 0.1µF C9 0.1µF L D2 BAT54A GL1 GH1 2 R 1 LX2 GH2 3 3 3 2 4 2 4 VDD *SEE TABLE 4 N1-B N2-B C1* LX1 VIN N1-A N2-A 5 6 5 6 1 1 J1-19 J1-17 J1-15 J1-13 J1-11 J1-9 J1-7 J1-5 J1-3 J1-1 N2-A LX2 N.C. N.C. N.C. N.C. N.C. GL2 GH2 SMBSUS SMBCLK SMBDATA J1-20 J1-18 J1-16 J1-14 J1-12 J1-10 J1-8 J1-6 J1-4 J1-2 Evaluate: MAX1895/MAX1995 VIN VFB2 VFB1 MAX1895 Evaluation Systems Figure 2. MAX1895 EV Kit Schematic _______________________________________________________________________________________ 9 Evaluate: MAX1895/MAX1995 MAX1895 Evaluation Systems T1 4 LX2 2 6 R12 2kΩ R11 150Ω 1% LAMP1 D3 1N4148W M1* IFB (PIN 22) C7 0.022µF VFB1 2 R17* C8 15pF 10 C18 0.01µF D1* D4* T2* 10 C17* R15* C13* R13* D5* LX1 C12 OPEN 4 6 VFB2 C14* C11 1µF *SEE TABLE 4 Figure 3. MAX1895 EV Kit Schematic—High-Voltage Section 1.0" Figure 4. MAX1895 EV Kit Component Placement Guide—Component Side 10 ______________________________________________________________________________________ LAMP2 MAX1895 Evaluation System Evaluates: MAX1895 1.0" Figure 5. MAX1895 EV Kit Component Placement Guide—Solder Side 1.0" Figure 6. MAX1895 EV Kit PC Board Layout—Component Side 1.0" Figure 7. MAX1895 EV Kit PC Board 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. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 11 © 2001 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.