MAX17244EVKIT# Analog Devices

Evaluates: MAX17244 MAX17244 Evaluation Kit General Description Quick Start The MAX17244 evaluation kit (EV kit) demonstrates Required Equipment the MAX17244 high-voltage, current-mode step-down MAX17244 EV kit converter with low operating current. The EV kit operates 14V, 1A DC power supply over a wide 6V to 36V input range and the output is set Electronic load capable of 2.5A for 5V at 2.5A. The EV Kit switching frequency is set at Digital voltmeter (DVM) 1.66MHz Procedure The EV kit comes with the MAX17244ETESA+ installed. The EV kit is fully assembled and tested. Follow the steps Features below to verify board operation. Caution: Do not turn on supplies until all connections are completed. Wide 6V to 36V Input Supply Range Forced-PWM or Skip-Mode Operation 1) Verify that jumpers JU1 and JU2 are in their default Configurable Switching Frequency positions, as shown in Table 1 and Table 2. Current-Mode Controller with Force-PWM and Skip 2) Connect the power supply between the EXT VBAT and Modes nearest PGND banana jacks. 86% Peak Efficiency at 12V Input in Skip-Mode 3) Connect the 2.5A electronic load between the OUT and nearest PGND banana jacks. 89% Peak Efficiency at 12V Input in Forced-PWM 4) Connect the DVM between the OUT and nearest PGND FSYNC Input and Power-Good Output banana jacks. Proven 4-Layer 2oz Copper PCB Layout 5) Turn on the power supply. Demonstrates 1065mil x 795mil Solution Size 6) Enable the electronic load. Fully Assembled and Tested 7) Verify that the voltage at the OUT test point is approximately 5V. Table 1. EN Configuration (JU1) Note: When a high input voltage or high load current is applied SHUNT continuously, an external cooling fan may be required to prevent DESCRIPTION POSITION MAX17244 from shutting down due to overtemperature. Connects the EN pin to the voltage at SUP 1-2* for normal operation. Connects the EN pin to ground to enter 2-3 shutdown mode. *Default position. Table 2. Mode of Operation (JU2) SHUNT Ordering Information appears at end of data sheet. MODE PIN MODE POSITION 1-2* Connected to BIAS Forced-PWM mode Connected to 2-3 Skip mode AGND Forced-PWM mode Connected to an Not installed (device syncs to an external clock external clock) *Default position. 19-8507 Rev 1 3/17Evaluates: MAX17244 MAX17244 Evaluation Kit Setting the Switching Frequency (FOSC) Detailed Description of Hardware The EV kit switching frequency is set to 1.66MHz by the The EV kit demonstrates the MAX17244 high-voltage, resistor, R (R2), connected from F to AGND. high-frequency, step-down converter with low operating FOSC OSC Refer to the Internal Oscillation section in the MAX17244 current. The EV kit operates over a wide 6V to 36V input IC data sheet for the equation and/or a graphical approach range and the output is set for 5V at 2.5A. to selecting the correct R (R2) value. FOSC Enable (EN) Power-Good Output (PGOOD) Place a shunt in the 1-2 position on jumper JU1 for normal The EV kit provides a PGOOD test point to monitor the operation. To place the device into shutdown mode, move status of the device output. PGOOD asserts when V the shunt on JU1 to the 2-3 position. OUT rises above 95% of its regulation voltage. PGOOD Synchronization Input (FSYNC) deasserts when V drops below 92% of its regulation OUT The EV kit features jumper JU2 to control the synchronization voltage. input (FSYNC). Connect FSYNC to AGND to enable skip- Output mode operation. Connect to BIAS or to an external clock Connect FB to BIAS for a fixed +5V (EV kit default to enable fixed-frequency forced-PWM mode operation. output) output voltage. To set the output to other The device can be synchronized to an external signal voltages between 1V and 10V, remove R12 and connect applied to FSYNC. To use an external clock, uninstall a resistive-divider from output (OUT) to FB to AGND. Use the shunt on JU2 and apply the signal at the FSYNC test the following formula to determine the R4 and R6 of the point. The external clock frequency at FSYNC can be resistive-divider network: higher or lower than the internal clock by 20%. Ensure that the duty cycle of the external clock used has a V OUT minimum 100ns pulse width. R4=R6 1 V FB Synchronizing Output (SYNCOUT) The EV kit provides a test point EXT 5V to pull up where V = 1V. FB the open-drain SYNCOUT to an external 5V supply. SYNCOUT is a 180 out-of-phase clock output relative to the internal oscillator at SYNCOUT to create cascaded power supplies with multiple MAX17244s. Component Suppliers SUPPLIER WEBSITE Murata Americas www.murata.com Panasonic Corp. www.panasonic.com Wrth Electronik GmbH & Co. KG www.we-online.com Samsung Electromechanics www.samsungsem.com Taiyo Yuden www.taiyo-yuden.com NXP Semiconductors www.nxp.com Note: Indicate that you are using the MAX17244 when contacting these component suppliers. Maxim Integrated 2 www.maximintegrated.com