Evaluates: MAX17530 (TDFN) in MAX17530 5V Output 5V Output Voltage Applications Evaluation Kit (TDFN) Procedure General Description The EV kit is fully assembled and tested. Follow the steps The MAX17530 5V evaluation kit (EV kit) (TDFN) is a fully below to verify board operation. Caution: Do not turn on assembled and tested circuit board that demonstrates the the power supply until all connections are completed. performance of this 42V, 25mA ultra-small, high-efficiency, synchronous step-down DC-DC converter in a 10-pin 1) Verify that shunts are installed on jumpers JU1, JU2 TDFN package. The EV kit operates over a wide input (EN/UVLO). voltage range of 6V to 42V and provides up to 25mA load 2) Verify that jumper JU3 (MODE-PFM operation) is open. current at 5V output. It draws only 26A supply current 3) Set the electronic load to constant-current mode, under no-load conditions (EN/UVLO connected to V ). IN 25mA, and disable the electronic load. The EV kit is programmed to switch at a frequency of 4) Connect the electronic loads positive terminal to the 220kHz. The device is simple to use and easily configurable VOUT PCB pad. Connect the negative terminal to with minimal external components. It features cycle-by- the GND PCB pad. cycle peak current-limit protection, undervoltage lockout, and thermal shutdown. 5) Connect the voltmeter across the VOUT and GND PCB pads. The EV kit comes installed with the MAX17530ATB+ in 6) Set the power-supply output to 24V. Disable the a 10-pin (3mm x 2mm) lead(Pb)-free/RoHS-compliant power supply. TDFN package. 7) Connect the power-supply output to the VIN PCB Features pad. Connect the supply ground to the GND PCB pad. 6V to 42V Input Voltage Range 8) Turn on the power supply. 5V Output, 25mA Continuous Current 9) Enable the electronic load and verify that output volt- 26A No-Load Supply Current age is 5V with respect to GND. EN/UVLO for On/Off Control and Programmable 10) Vary the input voltage from 6V to 42V. Input Undervoltage Lockout 11) Vary the load current from 1mA to 25mA and verify Programmable Switching Frequency that output voltage is 5V with respect to GND. Internal or Programmable Soft-Start Note: While performing an output short-circuit test, it is PFM or Forced-PWM Mode of Operation possible for the ceramic output capacitor to oscillate with the wiring inductance between the capacitor and short- Open-Drain RESET Output circuited load, and thereby cause the absolute maximum Peak Current-Limit Protection rating of the V pin (-0.3V) to be exceeded. The resis- OUT Thermal Shutdown tor (R7) and the capacitor (C5) are included on this EV kit PCB to protect against unintentional violation of the above Proven PCB Layout mentioned rating. In the actual system design, parasitic Fully Assembled and Tested board or wiring inductance should be minimized and the output-voltage waveform under short-circuit operation Quick Start should be verified to ensure that the absolute maximum rating of the V pin is not exceeded. Recommended Equipment OUT MAX17530 5V EV kit (TDFN) Ordering Information appears at end of data sheet. 42V adjustable, 0.5A DC power supply Electronic load up to 25mA Voltmeter 19-7697 Rev 0 6/15Evaluates: MAX17530 (TDFN) in MAX17530 5V Output Evaluation Kit (TDFN) 5V Output Voltage Applications RESET Output Detailed Description The EV kit provides a PCB pad to monitor the status of The MAX17530 5V EV kit (TDFN) is a fully assembled the RESET output. RESET goes high when the output and tested circuit board that demonstrates the perfor- voltage rises above 95% (typ) of its nominal regulated mance of the 42V, 25mA ultra-small, high-efficiency, output voltage. RESET goes low when output voltage falls synchronous step-down DC-DC converter in a 10-pin below 92% (typ) of its nominal regulated voltage. TDFN package. The EV kit operates over a wide input voltage range of 6V to 42V and provides up to 25mA load PFM or Forced-PWM Mode (MODE) current at 5V output. It draws only 26A supply current under The EV kit includes JU3 to select the mode of operation of no-load conditions (EN/UVLO connected to VIN). The EV the converter. Install a shunt across JU3 before powering kit is programmed to switch at a frequency of 220kHz. The up the EV kit to enable the forced-PWM operation. Keep device is simple to use and easily configurable with minimal JU3 open to enable the light-load PFM operation. See external components. It features cycle-by-cycle peak Table 2 for proper JU3 settings. current-limit protection, undervoltage lockout, and thermal Soft-Start shutdown. The EV kit offers a fixed 5ms soft-start time. Connect The EV kit includes an EN/UVLO PCB pad and jumpers capacitor C4 to adjust the soft-start time (t ). The SS JU1 and JU2 to enable control of the converter output. minimum soft-start time is related to the output The MODE PCB pad and JU3 are provided for selecting capacitance (C ) and the output voltage (V ) by the OUT OUT the mode of operation of the converter. A RESET PCB following equation. pad is available for monitoring the RESET output. The t > 0.05 x C x V RT/SYNC PCB pad can be used to synchronize the EV kit SS OUT OUT switching frequency to an external clock frequency. where t is in milliseconds and C is in F. SS OUT Use the following equation to determine the soft-start Enable Control (JU1, JU2) capacitance value (C ). SS The EN/UVLO pin on the EV kit serves as an on/off C = 6.25 x t control while also allowing the user to program the input SS SS undervoltage-lockout (UVLO) threshold. JU1 and JU2 where t is in milliseconds and C is in nanofarads. SS SS configure the EV kits output for turn-on/turn-off control. See External Synchronization (RT/SYNC) Table 1 for proper JU1, JU2 jumper configurations. The EV kit provides a PCB pad to synchronize the EV kit Additionally, resistors R1 and R2 are included to set the switching frequency to an external clock frequency. Refer UVLO to a desired turn-on voltage. Refer to the Setting to the External Synchronization section in the MAX17530 the Input Undervoltage-Lockout Level section in the IC data sheet for additional information on configuring the MAX17530 IC data sheet for additional information on external clock. setting the UVLO threshold voltage. Table 1. Enable Control (EN/UVLO) (JU1, JU2) SHUNT POSITION EN/UVLO PIN VOUT OUTPUT JU1 JU2 1-2 Open Connected to VIN Enabled Open 1-2 Connected to GND Disabled 1-2* 1-2 Connected to midpoint of R1, R2 resistor-divider Enabled at V 6V IN *Default position. Table 2. MODE Control (JU3) SHUNT POSITION MODE PIN MODE OF OPERATION 1-2 Connected to GND Forced PWM Open* Unconnected PFM *Default position. Maxim Integrated 2 www.maximintegrated.com