MAX20446 Evaluation Kit Evaluates: MAX20446 General Description Features The MAX20446 evaluation kit (EV kit) demonstrates the Demonstrates Robustness of the MAX20446 MAX20446 integrated 6-channel high-brightness (HB) Wide 4.5V to 36V Input Operating Range (Up to 52V 2 LED backlight driver with boost/SEPIC controller and I C Load Dump) interface for automotive displays. Powers HB LEDs (Up to Six Strings) for Medium-to- The EV kit operates from a DC supply voltage between Large-Sized LCD Displays in Automotive and Display 4.5V and 36V and the switching frequency can be set Backlight Applications 2 either at 2.2MHz or at 400kHz. The EV kit operates in I C 400kHz to 2.2MHz Resistor-Programmable Switching mode only. Spread-spectrum mode (SSM) is enabled by Frequency with Spread-Spectrum Option default for EMI improvement, but can be disabled by acting on a register bit. The EV kit demonstrates phase-shifted Phase-Shift Dimming Option pulse-width modulation (PWM) dimming. Dimming can be Demonstrates Cycle-by-Cycle Current Limit and performed externally using a PWM signal applied to the Thermal-Shutdown Features DIM PCB pad, or internally by programming the desired Demonstrates Wide Dimming Ratio 2 dimming frequency and individual duty cycle through I C. Demonstrates Fail-Safe Operation The hybrid dimming feature can be enabled through a register bit to reduce EMI. The EV kit also demonstrates 2 I C Programmability short-LED, open-LED, boost output undervoltage, as well Dedicated GUI as overvoltage- and overtemperature-fault protection. Proven PCB Layout and Thermal Design For operation at switching frequencies other than 2.2MHz Fully Assembled and Tested or 400kHz, the external components should be chosen according to the calculations in the MAX20446 IC data sheet. 2 The EV kit provides an I C interface that can oper- ate in conjunction with the Maxim command module Ordering Information appears at end of data sheet. 2 (MINIQUSB+) or a third-party I C master. The EV kit also includes, Windows -compatible software that provides a simple graphical user interface (GUI) for exercising the features of the IC. Windows is a registered trademark and registered service mark of Microsoft Corporation. 319-100163 Rev 0 3/18MAX20446 Evaluation Kit Evaluates: MAX20446 8) Verify that jumpers JMP1JMP3, JMP6JMP7 and MAX20446 EV Kit Files JMP9 have shunts installed across pins 1-2 (bleed FILE DESCRIPTION resistors connected, all current sinks enabled). MAX20446GUISetupV01.exe Windows GUI Installer 9) Connect the MINIQUSB+ interface boards P3 header to the J24 header on the EV kit. Quick Start 10) Connect the positive terminal of the power supply to the IN PCB pad. Connect the negative terminal of the Required Equipment power supply to a PGND PCB pad. MAX20446 EV kit 11) Connect a DVM across the OUT1 and GND PCB 5V to 36V, 4A DC power supply pads. Two digital voltmeters (DVMs) 12) Connect the six LED strings from VOUT to the OUT1, Six series-connected HB LED strings (6 LEDs each) OUT2, OUT3, OUT4, OUT5, and OUT6 PCB pads. rated to no less than 120mA 13) Clip the current probe across the channel 1 HB LED+ Current probe to measure the HB LED current wire to measure the LED current. MINIQUSB+ interface board with USB cable 14) Turn on the power supply and set to 12V. The green LED (DS1) should be on at this point. Windows-compatible PC with a spare USB port 15) Launch the EV kit software application. Procedure 16) From the EV kit software toolbar, select Device The EV kit is fully assembled and tested. Follow the steps 2 Scan for Address. The GUI scans the I C bus for below to verify board operation. available slave addresses on the bus and selects the Caution: Do not turn on the power supply until all 2 first one (in this case, the MAX20446 I C address). connections are completed. 2 Press OK once the MAX20446 I C address has been 1) Visit www.maximintegrated/evkitsoftware to found. download the latest version of the EV kit software, 17) Verify that the status bar in the bottom-right corner MAX20446GUISetupV01.exe. of the GUI displays EV Kit: Connected, as shown in 2) Install the EV kit software (GUI) on your PC by Figure 1. running the MAX20446GUISetupV01.exe program. 18) Select the desired OUT current value (45mA to The EV kit software application is installed together 120mA in 5mA steps) in the 0x02 ISET register group with the required MINIQUSB+ drivers. box by acting on the ISET slider bar, then click the 3) Verify that jumper J17 is closed and jumper J22 is Refresh button. open (2.2MHz switching frequency selected). 19) Check ENA to activate the driver in the 0x02 ISET 4) Verify that jumper J1 is closed (DS1 green LED register group box. connected). 20) Measure the voltage from each of the OUT PCB 5) Verify that jumper J23 is closed (FSEN function pads to PGND and verify the lowest voltage is 1V. disabled). 21) Measure the LED current using the current probe and 6) Verify that jumper J20 is closed (FLTB signaling verify all channels. enabled). 22) For more details on how to use the GUI and all the 7) Verify that a shunt is installed across pins 1-2 on features available, click on the GUI Help menu item. jumper J2 (device enabled). Maxim Integrated 2 www.maximintegrated.com