Evaluates: MAX4374/MAX4375 19-4542 Rev 0 4/09 MAX4374 Evaluation Kit General Description Features The MAX4374 evaluation kit (EV kit) provides a proven Precision Real-Time Current Monitoring design to evaluate the MAX4374 low-cost, micropower, Overcurrent Protection and Reset Circuits high-side current-sense supervisor that contains a high- side current-sense amplifier, bandgap reference, and Overvoltage Indicator Circuit comparator with latching output. This EV kit demonstrates 0 to 28V Input Common-Mode Range the MAX4374 in a 10-pin MAX package. The MAX4374 is also available in 14-pin SO, but that package is not 50A Supply Current compatible with this EV kit. 1mV (max) Input Offset Voltage The MAX4374 EV kit PCB comes with a MAX4374FEUB+ 2% (max) Full-Scale Accuracy installed, which is the 50V/V gain version. The MAX4374 EV kit can also be used to evaluate the MAX4374T Lead(Pb)-Free and RoHS Compliant (20V/V gain version), MAX4374H (100V/V gain version), Proven PCB Layout MAX4375T (20V/V gain version), MAX4375F (50V/V gain version), and MAX4375H (100V/V gain version). Contact Fully Assembled and Tested the factory for free samples of the pin-compatible MAX4374TEUB+, MAX4374HEUB+, MAX4375TEUB+, MAX4375FEUB+, or MAX4375HEUB+ devices. Ordering Information PART TYPE MAX4374EVKIT+ EV Kit MAX is a registered trademark of Maxim Integrated Products, Inc. +Denotes lead(Pb)-free and RoHS compliant. Component List DESIGNATION QTY DESCRIPTION DESIGNATION QTY DESCRIPTION 0.075 1%, 1/2W sensing resistor 0.1F 10%, 16V X7R ceramic R 1 (1206) C1 1 capacitor (0603) SENSE Murata GRM188R71C104K IRC LRC-LR1206LF-01-R075-F 4.7F 10%, 6.3V X5R ceramic R1, R3 2 10k 5% resistors (0603) C2 1 capacitor (0603) R2 1 100k 5% resistor (0603) Murata GRM188R60J475K R4 1 20k 5% resistor (0603) 0.22F 10%, 16V X7R ceramic R5 1 470k 5% resistor (0603) C3 1 capacitor (0603) R6 1 52.3k 1% resistor (0603) Murata GRM188R71C224K R8 1 205k 1% resistor (0603) 10F 20%, 25V X5R ceramic C4 1 capacitor (1206) R7, R9 2 10k 1% resistors (0603) Murata GRM31CR61E106K S1 1 Pushbutton switch C5 0 Not installed, capacitor Current-sense amplifier (10 MAX) U1 1 30V , 12A p- channel M OS FE T (6 S C 70) Maxim MAX4374FEUB+ M1 1 V i shay Si A421D J 1 PCB: MAX4374 Evaluation Kit+ 30V, 2.5A dual n-channel MOSFET M2 1 (6 SuperSOT) Fairchild FDC6561AN 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.MAX4374 Evaluation Kit Component Suppliers SUPPLIER PHONE WEBSITE Fairchild Semiconductor 888-522-5372 www.fairchildsemi.com IRC, Inc. 361-992-7900 www.irctt.com Murata Electronics North America, Inc. 770-436-1300 www.murata-northamerica.com Vishay 402-563-6866 www.vishay.com Note: Indicate that you are using the MAX4374 when contacting these component suppliers. 10) Slowly increase the sink current to above 1A. When Quick Start the OUT voltage reaches approximately 3.75V, the Recommended Equipment comparator output of the part trips the PMOS MAX4374 EV kit switches and shuts off the load-current path. 5V/10mA DC power supply 11) Verify that the overcurrent circuitry shuts off the load current. 12V/1.5A DC power supply 12) Reset the current path by pressing the S1 pushbut- An electronic load capable of sinking 1.1A (e.g., HP ton after an overcurrent condition. 6060B) Two digital voltmeters Detailed Description of Hardware The MAX4374 evaluation kit (EV kit) provides a proven Procedure design to evaluate the MAX4374 low-cost, micropower, The MAX4374 EV kit is fully assembled and tested. high-side current-sense supervisor that contains a high- Follow the steps below to verify the board operation. side current-sense amplifier, bandgap reference, and Caution: Do not turn on power supply or the elec- comparator with latching output. This EV kit demon- tronic load until all connections are completed. strates the MAX4374 in a 10-pin MAX package. The 1) Connect the positive terminal of the 5V supply to MAX4374 is also available in 14-pin SO, but that pack- the VCC pad. Connect the negative terminal of the age is not compatible with this EV kit. 5V supply to the GND pad. Measuring the Load Current 2) Connect the positive terminal of the 12V supply to The load current is measured as a voltage drop the VIN pad. Connect the negative terminal of the (V ) across an external sense resistor. This volt- SENSE 12V supply to the GND pad. age is then amplified by the current-sense amplifier and 3) Set the electronic load to sink 500mA. presented as a voltage at its output pin (OUT). Like all 4) Connect the electronic loads positive terminal to differential amplifiers, the output voltage has two com- the LOAD pad and the negative terminal to the ponents of error, an offset error and a gain error. The GND pad. offset error affects accuracy at low V and the SENSE gain error affects accuracy at large V . By mini- SENSE 5) Connect the first voltmeter across the OUT and GND mizing both offset and gain errors, accuracy can be pads. optimized over a wide dynamic range. 6) Connect the second voltmeter across the COUT2 and GND pads. Output-Voltage Calculation The MAX4374 EV kit is installed with a MAX4374FEUB+, 7) Turn on the power supplies. which has a gain of 50V/V. The current-sense resistor 8) Turn on the electronic load. (R ) value is 0.075 with 1% tolerance. The V SENSE OUT 9) Verify that the OUT voltmeter reading is approximately is given by: 1.875V and the COUT2 voltmeter is approximately 0V. V =I x R x A OUT LOAD SENSE V where A is the gain and I is the current load applied V LOAD to the device. Note that A for the MAX4374FEUB+ is V 50V/V. 2 Evaluates: MAX4374/MAX4375