Evaluates: MAX38800 MAX38800 Evaluation Kit General Description Features The MAX38800 evaluation kit (EV kit) serves as a reference High-Efficiency Solution platform for evaluating the MAX38800 voltage regulator Up to 96% Peak IC. This single-chip, integrated switching regulator Up to 95.5% Full-Load provides an extremely compact, highly efficient, fast, Up to 94% Light-Load Efficiency at 1A with accurate and reliable power delivery solution for low- DCM Enabled output voltage applications. The MAX38800 has different Inductor valley current limit is Configured to 7.5A programmability options to enable a wide range of (R SEL = R1 = 2.67k) configurations. Programmable Switching Frequency from 400kHz The EV kit consists of a fully-assembled and tested Printed to 900kHz Circuit Board (PCB) implementation of the MAX38800. Programmable Positive and Negative OCP Limit Jumpers, test points, and input/output connectors are included for flexibility and ease-of-use. Refer to the data Programmable Reference Voltage with External sheet for ordering information and more details. Input Option Fast Transient Response with Quick PWM Applications Architecture Servers/Servers Differential Remote Sense with Open-Circuit I/O and Chipset Supplies Detection GPU Core Supply DDR MemoryVDDQ and VTT Percentage-Based Output Power Good and OVP Point-of-Load (PoL) Applications Open-Drain Status Indicator (STAT) Pin Input Undervoltage and Overvoltage Lockout Ordering Information appears at end of data sheet. Adaptive Dead Time Control Integrated Boost Switch 19-Bump WLCSP (2.2mm x 2.8mm) Footprint Operation Using Ceramic Input and Output Capacitors Quick PWM is a trademark of Maxim Integrated Products, Inc. 319-100061 Rev 1 5/18Evaluates: MAX38800 MAX38800 Evaluation Kit Regulator enable Quick Start To enable the regulator, OE pin needs to be pulled high. If Required Equipment the on-board 1.8V LDO is active (the shunt on jumper J4 MAX38800 EV kit is in place), the output voltage can be used for the purpose. 12V, 10A DC power supply Installing a shunt on J15 (4-6) pulls the OE signal high to Load capable of sinking 7.5A 1.8V through a 20k resistor. To shut down the regulator Digital voltmeter a shunt needs to be installed on J10. This forces the OE Oscilloscope pin low. Procedure Status Pin The EV kit is fully assembled and tested. Follow the steps The MAX38800 has an open collector status (STAT) output below to verify the board operation. Caution: Do not turn to report fault or output undervoltage event. Install a shunt on power supply until all connections are completed. on J15 (3-5) to pull up this pin to V through a 20k CC 1) Connect a 12V power supply to the VDD1 and GND1 resistor. Since STAT pin is 3.3V tolerant, a shunt on J15 banana jacks. (1-3) can be installed to pull up this pin through a 20k resistor to the 3.3V provided by the on board regulator U3 2) Make sure the shunt is installed on: (install a shunt on J5 (3-4) to enable the LDO). a) J16 (1-2) to close the sense line. b) J4 (1-2) to power up the on-board LDO which Scenario Selection regulates 1.8V. Several parameters of the MAX38800 can be c) J12 (1-2) to provide the 1.8V bias supply to the programmed to allow optimization for specific applications. regulator from the on-board LDO. By selecting the appropriate value of resistor R SEL (R1) d) J15 (3-5) to pull up the STAT pin. and capacitor C SEL (C4), the optimum set of parameters e) J15 (4-6) to pull up the OE pin. (scenario) can be programmed. 3) Connect a voltmeter to the VOUT and GND banana While R SEL selects the proper scenario, C SEL determines jacks (J8, J11, J13, and J14 can be used as well). the nominal F . The MAX38800 features a configuration SW 4) Turn on the power supply. table to provide a wide range of options. Table 1 shows 5) Verify that the voltmeter reads 3.3V. the scenario table for MAX38800. Detailed Description of Hardware The MAX38800 provides compact, high-efficiency power delivery for precision outputs that demand fast transient response. The 19-ball (2.2mm x 2.8mm) CSP package minimizes the PCB area. The EV kit is preset for 3.3V output and can provide up to 7.5A from a 6.5V to 14V input supply. Bias Supply The MAX38800 EV kit has an on-board LDO (U2) that can provide the required 1.8V VCC bias voltage to both the regulator and pullup voltage for the Output Enable (OE) input. This allows testing the part using a single external power supply. To enable the on-board LDO install the shunt on jumper J4. To effectively use the LDO to supply the VCC bias voltage to the regulator also install the shunt on jumper J12. In order to properly measure the efficiency of the regulator, the LDO should not be active. The shunts on J4 and J12 need to be removed to disable the LDO. An external 1.8V, 0.1A current-limited power supply needs to be connected between J12-2 and ground. The same signal should be connected to J10 (1-2) to pull up the OE pin. Maxim Integrated 2 www.maximintegrated.com