Click here for production status of specific part numbers. Evaluates: MAX40661 MAX40661 Evaluation Kit General Description Features The MAX40661 evaluation kit (EV kit) is a fully assembled Easy Electrical Evaluation of the MAX40661 electrical demonstration kit that provides a proven design EV Kit Designed for 50 Interfaces to evaluate the MAX40661 transimpedance amplifiers. -40C to +125C Temperature Range Tested 10-TDFN-EP MAX40661ATB/VY+ Device Note that the MAX40661 EV kit provides an electrical Accommodates Easy-to-Use Components interface to the IC that is similar, but not the same as a Proven PCB Layout photodiode. Fully Assembled and Tested The MAX40661 EV kit PCB comes with a MAX40661ATB/ VY+ installed. Ordering Information appears at end of data sheet. MAX40661 EV Kit Photo 319-100401 Rev 0 7/19Evaluates: MAX40661 MAX40661 Evaluation Kit Quick Start Detailed Description of Hardware The MAX40661 accepts AC and DC-coupled input from a Required Equipment high-speed photodiode. The EV kit facilitates evaluation of +3.6V, 100mA DC power supply the MAX40661 TIA without a photodiode. The MAX40661 Signal source up to 1GHz TIA is designed to be used with optical transceiver systems when the detectors (APD, PIN diodes) cathode 500MHz to 2.5GHz oscilloscope connected to the IN input of the IC. The device is to be Procedure used when AC input currents are flowing out of the device The MAX40661 EV kit is fully assembled and tested. at IN input of the IC. Follow the below to verify board operation: When an APD with negative bias voltage is connected to the TIA input the signal current flows out of the amplifiers Caution: Do not turn on the power supply or the electronic summing node. The input current flows through an internal load until all the connections are complete. load resistor to develop a voltage that is then applied to the 1) Connect a +3.3V supply and ground to VIN SUPPLY input of the second stage. An internal clamp circuit protects connector and GND return pad of the EV kit, respectively. against input currents up to 100mA up to 100ns and up to Disable the output of the power supply. 2A for 10ns pulses at low duty cycles. For more information 2) Install a shunt on 2-3 of jumper J1 to enable the TIA. about the device, please refer to the IC data sheet. (Installing a shunt on 1-2 on jumper J1 will force the Theory of Operation TIA into low power disable mode.) 3) Install a shunt on 2-3 of jumper J2 to select low gain The MAX40661 EV kit provides photodiode emulation mode (25k transimpedance). (Installing a shunt using a simplified electrical photodiode model. The model on 1-2 of jumper J2 selects high gain mode (50k provides a 50 electrical input termination, and resistors transimpedance)). that convert the high-speed input voltage to high-speed 4) Connect a signal source to IN AC (J4) edge-mount current. A DC path is provided to model the average SMA input. Set the signal amplitude to 12.5mV photodiode current. P-P (4.4mV or -34dBm), which corresponds to RMS Test Interface 2.5A . Set the frequency to 100MHz. Disable the P-P The MAX40661 outputs are back terminated with 50. signal generator output. When terminating the outputs to 50 oscilloscope, the 5) Connect OUT1+ (J7) and OUT- (J6) edge-mount ac-coupling capacitors C6 and C7 are present and resistor SMA outputs to the 50 inputs of a high-speed R0 is not installed. When interfacing with subsequent oscilloscope. amplifiers or LVDS- capable devices, ac-coupling capacitors 6) Verify all the shunts are in default positions, as (C6, C7) and 100 resistor (R0) are installed when the shown in Table 1. subsequent device has internal bias. Replace C6 and C7 7) Enable the power supply and signal generator output. ac coupling capacitors with 0 resistors in case of DC Observe for outputs from OUT+ and OUT- on the coupling into the device. oscilloscope. 8) The differential signal at the oscilloscope should be Input and OFFSET Input DC Evaluation approximately 62.5mV at 100MHz. P-P The MAX40661 EV kit features DC evaluation of IN input and OFFSET input. Table 1. Jumper Function When evaluating the MAX40661s IN input in DC mode at JUMPER I DC IN (J3) using a calibrator with current output option, POSITION FUNCTIONS LABEL 0 is installed at resistor R3, capacitors CIN1 and CIN2 are 2-3* Enables U1. Active Mode removed. Current value set in microamperes will provide J1 a differential voltage output function of transimpedance Disables U1 or Low Power 1-2 selected. Disable Mode When evaluating the MAX40661s IN input in DC mode Low Gain Mode Selected J2 2-3* at I DC IN (J3) using a calibrator with voltage output (25k Transimpedance) option, 0 is installed at resistor R3, and capacitors C8, High Gain Mode Selected 1-2 CIN1 and CIN2 are removed. Resistor R1 and R2 sets the (50k Transimpedance) input resistance (Rs), and the bias voltage at IN (V ) is IN *Default position. Maxim Integrated 2 www.maximintegrated.com