19-5782 Rev 0 3/11 MAX44265 Evaluation Kit Evaluates: MAX44265 General Description Features The MAX44265 evaluation kit (EV kit) provides a proven S +1.8V to +5.5V Supply Voltage Range design to evaluate the MAX44265 low-power, MOS-input S Accommodates Multiple Op-Amp Configurations operational amplifier (op amp) in a 6-bump wafer-level S Component Pads Allow for Sallen-Key Filter package (WLP). The EV kit circuit is preconfigured as a S Rail-to-Rail Inputs/Outputs noninverting amplifier, but can easily be adapted to other topologies by changing a few components. Low power, S Accommodates Easy-to-Use 0805 Components low-input V , and rail-to-rail input/output stages make OS S Proven PCB Layout this device ideal for a variety of measurement applica- S Fully Assembled and Tested tions. The component pads accommodate 0805 pack- ages, making them easy to solder and replace. The EV kit comes with a MAX44265EWT+ installed. Ordering Information appears at end of data sheet. Component List DESIGNATION QTY DESCRIPTION DESIGNATION QTY DESCRIPTION R1, R2 2 1kI Q1% resistors (0805) 0.1FF Q10%, 16V X7R ceramic C1 1 capacitor (0603) R5 1 10kI Q1% resistor (0805) Murata GRM188R71C104K R6, R8 2 0I Q5% resistors (0805) 4.7FF Q10%, 6.3V X5R ceramic Single low-power, rail-to-rail C2 1 capacitor (0603) U1 1 I/O op amp (6 WLP) Murata GRM188R60J475K Maxim MAX44265EWT+ 2 Shunts Not installed, ceramic capacitors C3, C4, C8, C9 0 (0805) PCB: MAX44265 EVALUATION 1 KIT JU1 1 2-pin header JU2 1 3-pin header Component Supplier SUPPLIER PHONE WEBSITE Murata Electronics North America, Inc. 770-436-1300 www.murata-northamerica.com Note: Indicate that you are using the MAX44265 when contacting this component supplier. 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.MAX44265 Evaluation Kit Evaluates: MAX44265 Op-Amp Configurations Quick Start The device is a single-supply op amp that is ideal for differential sensing, noninverting amplification, buffering, Required Equipment and filtering. A few common configurations are detailed MAX44265 EV kit in the next few sections. +5V, 10mA DC power supply (PS1) Noninverting Configuration Precision voltage source The EV kit comes preconfigured as a noninverting ampli- Digital multimeter (DMM) fier. The gain is set by the ratio of R5/R1. The EV kit comes preconfigured for a gain of +11. For a voltage applied to Procedure the IN+ PCB pad, the output voltage for the noninverting The EV kit is fully assembled and tested. Follow the steps configuration is given by the equation below: below to verify board operation: 1) Verify that the jumpers are in their default positions, as R5 shown in Table 1. V = (1+ )(V + V ) OUT IN+ OS R1 2) Connect the positive terminal of the +5V supply to the VDD PCB pad and the negative terminal to the GND where V = Input-referred offset voltage. OS PCB pad closest to VDD. Differential Amplifier 3) Connect the positive terminal of the precision voltage To configure the EV kit as a differential amplifier, replace R1, source to the IN+ PCB pad. Connect the negative R2, R , and R5 with appropriate resistors. When R1 = R2 C3 terminal of the precision voltage source to GND (GND and R = R5, the CMRR of the differential amplifier is deter- C3 or IN- PCB pads). mined by the matching of resistor ratios R1/R2 and R /R5: C3 4) Connect the DMM to monitor the voltage on the OUT PCB pad. With the 10kI feedback resistor (R5) and R5 V = Gain(V V ) + (1 + )V OUT IN+ IN OS 1kI series resistor (R1), the gain is +11 (noninverting R1 configuration). where: 5) Turn on the +5V power supply. 6) Apply 100mV from the precision voltage source. R5 R C3 Gain= = Observe the output at OUT on the DMM. OUT should R1 R2 read approximately +1.1V. 7) Apply 400mV from the precision voltage source. OUT Sallen-Key Configuration should read approximately +4.4V. The Sallen-Key topology is ideal for filtering sensor signals with a 2nd-order filter and acting as a buffer. Detailed Description of Hardware Schematic complexity is reduced by combining the filter and buffer operations. The EV kit can be configured in The MAX44265 EV kit provides a proven layout for the a Sallen-Key topology by replacing and populating a MAX44265 low-power, MOS-input op amp. The device is few components. The Sallen-Key topology is typically a single-supply op amp that is ideal for buffering sensor configured as a unity-gain buffer, which can be done signals. The Sallen-Key topology is easily accomplished by replacing R1 and R5 with 0I resistors. The signal is by changing and removing some components. The noninverting and applied to IN+. The filter component Sallen-Key topology is ideal for buffering and filtering pads are R2, R3, R4, and R8, where some have to be sensor signals. populated with resistors and others with capacitors. Table 1. Jumper Descriptions (JU1, JU2) JUMPER SHUNT POSITION DESCRIPTION Installed* Connects the IN- PCB pad to GND. JU1 Not installed Isolates the IN- PCB pad from GND. 1-2* Connects SHDN to VDD (normal operation). JU2 2-3 Connects SHDN to GND (shutdown). *Default position. Maxim Integrated Products 2