MAX44246 Evaluation Kit Evaluates: MAX44246 General Description Features The MAX44246 evaluation kit (EV kit) provides a proven Accommodates Multiple Op-Amp Configurations design to evaluate the MAX44246 ultra-precision, low- Component Pads Allow for Sallen-Key Filter noise, low-drift dual-operational amplifiers (op amps) in an Accommodates Easy-to-Use Components M 8-pin MAX package. The EV kit circuit is preconfigured as noninverting amplifiers, but can be adapted to other Proven PCB Layout topologies by changing a few components. Fully Assembled and Tested The EV kit comes with a MAX44246AUA+ installed. Ordering Information appears at end of data sheet. Component List DESIGNATION QTY DESCRIPTION DESIGNATION QTY DESCRIPTION R1, R2, R9, 0.1F 10%, 50V X7R ceramic 4 1k 1% resistors (0603) R10 C1, C17 2 capacitors (0603) Murata GRM21BR71H104K R3, R4, R7, 0 Not installed, resistors (0603) R11, R12, R15 4.7F 10%, 50V X7R ceramic C2, C18 2 capacitors (1206) R5, R13 2 10k 1% resistors (0603) Murata GRM31CR71H475K R6, R8, R14, 4 0 5% resistors (0603) R16 Not installed, ceramic capacitors (0603) Not installed, miniature test TP1, TP2 0 C3C16 0 C3, C6, C7, C8, C10, C13C15 points are open C4, C5, C9, C11, C12, Low-noise, precision, dual op C16 are short (PC trace) U1 1 amp (8 MAX) Maxim MAX44246AUA+ INMA, INMB, INPA, INPB, 6 Red multipurpose test points 5 Shunts OUTA, OUTB PCB: MAX44246 EVALUATION 1 JU1JU5 5 2-pin headers KIT Component Supplier SUPPLIER PHONE WEBSITE Murata Electronics North America Inc. 770-436-1300 www.murata-northamerica.com Note: Indicate that you are using the MAX44246 when contacting this component supplier. MAX is a registered trademark of Maxim Integrated Products, Inc. 19-6509 Rev 0 12/12MAX44246 Evaluation Kit Evaluates: MAX44246 operating with a single supply, short V to GND using EE Quick Start jumper JU5. Required Equipment Op-Amp Configurations MAX44246 EV kit The device is a single/dual-supply dual op amp that is +36V, 10mA DC power supply (PS1) ideal for differential sensing, noninverting amplification, Two precision voltage sources buffering, and filtering. A few common configurations are shown in the next few sections. Two digital multimeters (DMMs) The following sections explain how to configure one of the Procedure devices op amps (op amp A). To configure the devices The EV kit is fully assembled and tested. Follow the steps second op amp (op amp B), the same equations can be below to verify board operation : used after modifying the component reference designators. 1) Verify that all jumpers (JU1JU5) are in their default Noninverting Configuration positions, as shown in Table 1. The EV kit comes preconfigured as a noninverting ampli- 2) Conn ect the positive terminal of the +36V supply to fier. The gain is set by the ratio of R5 and R1. The EV kit VCC and the negative terminal to GND and VEE. comes preconfigured for a gain of +11. The output voltage 3) Conn ect the positive terminal of the precision voltage for the noninver ting configuratio n is given by the equation source to INPA. Connect the negative terminal of the below: precision voltage source to GND. INMA is already con- R5 nected to GND through jumper JU1. V =(1+)V V OUT A INPA OS R1 4) Conn ect the positive terminal of the second preci- sion voltage source to the INPB PCB pad. Connect Inverting Configuration the negative terminal of the precision voltage source To configure the EV kit as an inverting amplifier, remove to GND. INMB is already connected to GND through the shunt on jumper JU1 and install a shunt on jumper jumper JU3. JU2 and feed an input signal on the INMA PCB pad. 5) Conn ect the DMMs to monitor the voltages on OUTA and OUTB. With the 10k feedback resistors and 1k Differential Amplifier series resistors, the gain of each noninverting amplifier To configure the EV kit as a differential amplifier, replace is +11. R1R3 and R5 with appropri ate resistors. When R1 = R2 and R3 = R5, the CMRR of the differential amplifier 6) Turn on the +36V power supply. is determined by the matching of the resistor ratios R1/ 7) Apply 100mV from the precision voltage sources. R2 and R3/R5. Observe the output at OUTA and OUTB on the DMMs. Both should read approximately +1.1V. V GAIN(V V ) OUT A I NPA I NMA 8) Apply 400mV from the precision voltage sources. Both where: OUTA and OUTB should read approximately +4.4V. R5 R3 Note: For dual-supply operation, a 2.7V to 18V can GAIN R1 R2 be applied to VDD and VEE, respectively. In this case, remove the shunt on jumper JU5. The rest of the procedure Sallen-Key Configuration remains the same as that of the single-supply operation. The Sallen-Key topology is ideal for filtering sensor sig- Detailed Description of Hardware nals with a second-order filter and acting as a buffer. Schematic complexity is reduced by combining the filter The MAX44246 EV kit provides a proven layout for the and buffer operations. The EV kit can be configured in a MAX44246 ultra-precision, low-noise, low-drift, dual op Sallen-Key topology by replacing and populating a few amp. The device is a single/dual-supply, dual op amp (op components. The Sallen-Key topology can be configured amp A and op amp B) that is ideal for ADC buffers. as a unity-gain buffer by replacing R5 with 0 resistor The default configuration for the device in the EV kit and removing resistor R1. The signal is noninverting and is single-supply operation in noninverting configuration. applied to INPA. The filter component pads are R2R4 However, the device can operate with a dual supply as and R8, where some have to be populated with resistors long as the voltage across the V and GND pins of the DD and others with capacitors. IC do not exceed the absolute maximum ratings. When Maxim Integrated 2 www.maximintegrated.com = = =