19-4465; Rev 0; 2/09 MAX4173 Evaluation Kit The MAX4173 evaluation kit (EV kit) is a fully assembled and tested surface-mount PCB that contains a MAX4173TEUT+. The MAX4173 is a high-side, currentsense amplifier with an input common-mode voltage range that extends from 0 to 28V. The current-sense amplifier provides an analog voltage output proportional to the load current flowing through an external sense resistor. The 20V/V gain version of the MAX4173 (MAX4173TEUT+) and a 150m sense resistor are installed on the board. Other gain versions of the MAX4173 can be evaluated by replacing the MAX4173TEUT+ with a MAX4173FEUT+ (50V/V) or a MAX4173HEUT+ (100V/V) and a user-supplied, external sense resistor. The user can easily match the full-scale sense voltage to the required output-voltage range. Features o Real-Time Current Monitoring o Wide 0 to 28V Input Common-Mode Range Independent of Operating Supply Voltage o 0.5% Full-Scale Accuracy o Lead(Pb)-Free and RoHS Compliant o Fully Assembled and Tested Ordering Information PART TYPE MAX4173EVKIT+ EV kit +Denotes lead(Pb)-free and RoHS compliant. Component List DESIGNATION QTY C1 1 0.1F 10%, 50V X7R ceramic capacitor (0603) Murata GRM188R71H104K 1 4.7F 10%, 50V X7R ceramic capacitor (1210) Murata GRM32ER71H475K C2 C3, C4, C5 C6 R1 0 DESCRIPTION DESIGNATION QTY R2, R3, R4 0 Not installed, resistors--short (PC trace) (0603) RS+, RS- 2 Binding posts Multipurpose test point, orange TP1 1 TP2, TP4, TP6 3 Multipurpose test points, black TP3, TP5 2 Multipurpose test points, red U1 1 High-side current-sense amplifier (6 SOT23) Maxim MAX4173TEUT+ -- 1 PCB: MAX4173 Evaluation Kit+ Not installed, ceramic capacitors (1210) 0 Not installed, ceramic capacitor (0603) 1 0.15 1%, current-sense resistor (1206) IRC LR1206LF-R150-F DESCRIPTION Component Suppliers SUPPLIER PHONE WEBSITE IRC, Inc. 361-992-7900 www.irctt.com Murata Electronics North America, Inc. 770-436-1300 www.murata-northamerica.com Note: Indicate that you are using the MAX4173 when contacting these component suppliers. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim's website at www.maxim-ic.com. 1 Evaluates: MAX4173 General Description Evaluates: MAX4173 MAX4173 Evaluation Kit Quick Start Detailed Description of Hardware Recommended Equipment The MAX4173 IC is a current-sense amplifier that measures the load current and provides an analog voltage output. The full-scale VSENSE is set to 150mV. The fullscale ISENSE is set at 1A. They can be changed by replacing current-sense resistor R1 to another appropriate value. * One 12V, 2A power supply * One electronic load capable of sinking 1A * Two digital voltmeters (DVMs) Procedure The MAX4173 EV kit is fully assembled and tested. Follow the steps below to verify board operation. Caution: Do not turn on the power supply or the electronic load until all connections are completed. 1) Set the power supply to 12V and connect the positive terminal to test point TP3 (VCC) on the EV kit. Connect the ground of the power supply to test point TP4 (GND) on the EV kit. 2) Connect the positive terminal of the 12V power supply to binding post RS+ on the EV kit. Applying the VCC Power Supply and the Load Power Supply The MAX4173 EV kit is installed with a MAX4173TEUT+, which has a gain of 20V/V. The current-sense resistor value is 0.15. The VOUT is given by: VOUT = VSENSE x AV = ISENSE x 0.15 x 20 where VSENSE is the sense voltage, ISENSE is the load current, and AV is the gain of the device. Normal operating VCC is from 3V to 28V. RS+ and RSrange is 0 to 28V. 3) Set the electronic load to sink 1A. 4) Connect the positive terminal of the electronic load to binding post RS- on the EV kit. 5) Connect the negative terminal of the electronic load to the ground of the power supply. 6) Connect a voltmeter across test point TP5 (RS+) and test point TP6 (RS-). 7) Connect the second voltmeter across test points TP1 (OUT) and TP2 (GND). 8) Turn on the power supply. 9) Turn on the electronic load. 10) Verify that the first DVM reading is approximately 150mV and the second DVM is approximately 3V. 11) Adjust the electronic load current to between 1A and 0A and verify that the reading of the second DVM is approximately 20 times the reading of the first DVM. Measuring the Load Current The load current is measured as a voltage drop (VSENSE) across an external sense resistor. This voltage is then amplified by the current-sense amplifier and presented at its OUT pin. The MAX4173 EV kit, which is assembled with the MAX4173TEUT+, is designed with a full-scale sense voltage drop of 150mV. For a typical 1A full-scale load current, this results in the use of a 0.15 sense resistor on the MAX4173 EV kit using the following equation: R1 = VSENSE _ FULL _ SCALE ILOAD _ FULL _ SCALE For different full-scale sense voltage and full-scale load-current arrangements, the equation above can be used to determine the appropriate current-senseresistor values. Refer to the Recommended Component Values section in the MAX4173 IC data sheet for further guidance. Evaluating the MAX4173FEUT+/MAX4173HEUT+ The MAX4173 EV kit can also be used to evaluate other gain versions of the MAX4173 (20V/V, 50V/V, 100V/V = T, F, H suffix, respectively). Replace U1 with a different version of the MAX4173 and refer to the Recommended Component Values section in the MAX4173 IC data sheet for additional information. 2 _______________________________________________________________________________________ MAX4173 Evaluation Kit Evaluates: MAX4173 Figure 1. MAX4173 EV Kit Schematic _______________________________________________________________________________________ 3 Evaluates: MAX4173 MAX4173 Evaluation Kit Figure 2. MAX4173 EV Kit Component Placement Guide-- Component Side Figure 3. MAX4173 EV Kit PCB Layout--Component Side Figure 4. MAX4173 EV Kit PCB Layout--Solder Side Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 4 ___________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 (c) 2009 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc. Mouser Electronics Authorized Distributor Click to View Pricing, Inventory, Delivery & Lifecycle Information: Maxim Integrated: MAX4173EVKIT+