Evaluates: MAX16974 19-5661 Rev 0 12/10 MAX16974 Evaluation Kit General Description Features S Wide 3.5V to 28V DC Supply Range The MAX16974 evaluation kit (EV kit) provides a proven design to evaluate the MAX16974 high-voltage, 2.2MHz, S 42V Input Transient Tolerance 2A automotive step-down controller with low operating S Proven PCB Layout current. It is designed to operate with 3.5V to 28V input S Fully Assembled and Tested voltages, while using only 35A quiescent current at no load. The switching frequency is adjustable from 220kHz Ordering Information to 2.2MHz and the output voltage is pin selectable at 5V fixed or 1V to 10V adjustable. This EV kit is initially set up PART TYPE to operate at 2.2MHz with a 5V output. MAX16974EVKIT+ EV Kit The EV kit PCB comes with a MAX16974AUE/V+ installed. +Denotes lead(Pb)-free and RoHS compliant. Component List DESIGNATION QTY DESCRIPTION DESIGNATION QTY DESCRIPTION 0.1F Q10%, 6.3V X5R ceramic 2.2F Q10%, 10V X7R ceramic CBST 1 capacitor (0402) CVL 1 capacitor (0603) TDK C1005X5R0J104K Murata GRM188R71A225K 3A, 60V Schottky diode 5600pF Q10%, 50V X7R ceramic D1 1 Diodes Inc. B360B CCOMP1 1 capacitor (0603) Murata GRM188R71H562K JU1 1 3-pin header JU2, JU7 0 Not installed, 0I jumpers (0603) Not installed, 120pF Q5%, 50V CCOMP2 0 C0G ceramic capacitor (0603) JU3, JU6, 3 0I Q5% resistors (0603) Murata GRM1885C1H121J RTEST 100pF Q5%, 50V C0G ceramic 4.7H Q20%, 2.8A, 20mI CCRES 1 capacitor (0603) L1 1 inductor (7.0mm x 7.5mm) Murata GRM1885C1H101J Panasonic ETQP5M4R7YFM Not installed, ceramic capacitor Not installed, multipurpose test CFB1 0 LX 0 (0603) point RCOMP 1 20kI Q1% resistor (0603) 47F Q20%, 50V electrolytic CIN1 1 capacitor (D8) RFB1, RFB2, 0 Not installed, resistors (0603) Panasonic EEE-FK1H470XP RFB3 RFOSC 1 12.1kI Q1% resistor (0603) 0.1F Q10%, 50V X7R ceramic CIN2, CIN3 2 RFSYNC 1 20kI Q5% resistor (0603) capacitors (0603) Murata GRM188R71H104K RRESB 1 10kI Q5% resistor (0603) Not installed, 3I Q5% resistor 4.7F Q10%, 50V X7R ceramic RSNUB 0 (0603) CIN4, CIN5 2 capacitors (1210) Murata GRM32ER71H475K High-voltage automotive step- U1 1 down converter (16 TSSOP-EP*) 22F Q20%, 10V X7R ceramic Maxim MAX16974AUE/V+ COUT, COUT2 2 capacitors (1210) Murata GRM32ER71A226K 1 Shunts PCB: MAX16974 EVALUATION Not installed, 1000pF Q10%, 50V 1 KIT+ CSNUB 0 X7R ceramic capacitor (0603) Murata GRM188R71H102K *EP = Exposed pad. /V denotes an automotive qualified part. Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com.MAX16974 Evaluation Kit Component Suppliers SUPPLIER PHONE WEBSITE Diodes Incorporated 805-446-4800 www.diodes.com Murata Electronics North America, Inc. 770-436-1300 www.murata-northamerica.com Panasonic Corp. 800-344-2112 www.panasonic.com TDK Corp. 847-803-6100 www.component.tdk.com Note: Indicate that you are using the MAX16974 when contacting these component suppliers. External Clock Input (FSYNC) Quick Start The IC synchronizes to an external clock signal applied Recommended Equipment at FSYNC. The signal at FSYNC must have a 10% higher MAX16974 EV kit frequency than the internal clock period for proper synchronization. 12V at 2A DC power supply Digital voltmeter (DVM) Output-Voltage/RESET Threshold 2A DC load (2.5I, 10W) Resistive-Divider Network The output voltage of the IC can be programmed Procedure between 1V and 10V. Although the ICs output voltage The EV kit is fully assembled and tested. Follow the steps and reset threshold can be set individually, the EV kit below to verify board operation: supports the use of a combined resistive-divider network 1) Verify that all jumpers (JU1, JU2, JU3, JU6, and JU7) to set the desired output voltage and the reset threshold are in their default positions, as shown in Table 1. using three resistors (RFB1, RFB2, and RFB3). Use the following formula to determine the RFB3 of the resistive- 2) Connect the DVM between the VOUT and GND pads. divider network: 3) Connect the load between the VOUT and GND pads. 4) Connect the power supply between the EXT VBAT RFB3= RFB1+RFB2+RFB3 V /V ( ) REF OUT and GND pads. where V = 1V and V is the desired output voltage. REF OUT 5) Enable the 12V power supply. 6) Verify that VOUT = 5V. RFB2= RFB1+RFB2 +RFB3 V /V RFB3 (( ) ) REF RES RES 7) Verify that RESB is high. where V is 1.2V (refer to the Electrical REF RES Characteristics section in the MAX16974 IC data sheet) Detailed Description of Hardware and V is the desired reset threshold in volts. RES The MAX16974 EV kit provides a proven layout for the MAX16974 IC. The EV kit is designed to fully demon- The precision of the reset-threshold function is depen- strate the functionality of the IC as follows: dent on the tolerance of the resistors used for the divider. Refer to the MAX16974 IC data sheet for details. Verify output-voltage regulation Some applications require the addition of a compensa- V e r i f y p o w e r - g o o d b e h a v i o r a n d r e s e t - t h r e s h o l d tion capacitor at CFB1. Contact the factory for applica- selection tions assistance. Easy programmability of different output voltages The 0I resistors at JU3 and JU6 must be moved to between 1V and 10V locations JU2 and JU7 to enable the combined resistive- Startup and shutdown performance divider network. As shipped from the factory, the 0I Current-limit performance resistors are installed at JU3 and JU6, so that FB is tied to VL and RESETI is tied to ground, selecting the factory The following detailed descriptions enable the user to settings. program the EV kit per application requirements. 2 Evaluates: MAX16974