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1 9-97; Rev 0; 8/04 MAX406 Evaluation Kit General Description The MAX406 evaluation kit (EV kit) is a fully assembled and tested surface-mount circuit board that demonstrates the MAX406 logarithmic amplifier. The MAX406 computes the log ratio of an input current relative to a reference current and provides a corresponding voltage output with a default 0.5V/decade scale factor. The EV kit operates from a single +.7V to +V supply or from dual ±.7V to ±5.5V supplies, with the ability to select one of four reference currents. The MAX406 EV kit can be used to evaluate the MAX407 by changing the IC and the input RC networks R, R, C7, and C8. C C C C6 4 C7, C8 0µF ±0%, 6V X5R ceramic capacitor (06) TDK C6X5RC06M 0µF ±0%, 6.V X5R ceramic capacitor (0805) Taiyo Yuden JMKBJ06MG or TDK C0X5R0J06M 0.µF ±0%, 5V X7R ceramic capacitors (060) TDK C608X7RE04K 00pF ±5%, 50V C0G ceramic capacitors (060) Murata GRM885CH0J or TDK C608C0GH0J D, D 0 Not installed, photodiode (TO-46) R, R 00Ω ±% resistors (060) R 0 Not installed, resistor (060) R4 0 Not installed, potentiometer R5 0.kΩ ±0.%, precision chip resistor (060) ICR PCF-W060R-0-0-B or Vishay P060K0BB Features +.7V to +V Single-Supply Operation or ±.7V to ±5.5V Dual-Supply Operation Selectable 0nA/00nA/µA/0µA On-Board Reference Current Adjustable Output Scale Factor Surface-Mount Construction Fully Assembled and Tested Ordering Information PART TEMP RANGE PIN PACKAGE MAX406EVKIT 0 C to +70 C 6 Thin QFN-EP* (4mm x 4mm) *EP = Exposed paddle. Note: To evaluate the MAX407, order a MAX407ETE free sample with the MAX406EVKIT. Component List R6 R9 4 R0 R R R R4 0 0kΩ ±0.%, precision chip resistors (060) IRC PCF-W060R-0-00-B or Vishay P060K00BB 4.99MΩ ±, precision chip resistor (0805) IRC CR0805F4M99D or Vishay DP PN 499kΩ ±, precision chip resistor (0805) IRC PCF-W0805R D or Vishay DP PN 49.9kΩ ±, precision chip resistor (060) IRC PCF-W060R D or Vishay DP PN 4.99kΩ ±, precision chip resistor (060) IRC PCF-W060R D or Vishay DP PN Not installed, shorted by PC trace (060) Evaluates: MAX406/MAX407 Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at , or visit Maxim s website at

2 MAX406 Evaluation Kit Evaluates: MAX406/MAX407 U J, J 0 JU, JU6, JU9, JU0, JU MAX406ETE (6-pin TQFN 4mm x 4mm) Not installed, edge-mount SMA connectors 5 -pin headers Quick Start The MAX406 EV kit is a fully assembled and tested surface-mount board. Follow the steps below for board operation. Do not turn on the power supply until all connections are complete. Recommended Equipment Current source capable of sourcing 0nA to ma current Single +.7V to +V, 0mA DC power supply Evaluating the MAX406 with Single Supply ) Verify that shunts are connected across jumpers JU and JU (single-supply operation, sets CMVIN = CMVOUT). ) Verify that shunts are connected across jumpers JU4 (pins and 4), JU5 (pins and ), JU6, and JU7 (pins and ) (sets output scale factor K = V/decade). ) Verify that shunts are connected across jumpers JU8 (pins and ) and JU (pins and ) (sets onboard reference current = 00nA). 4) Verify that there is no shunt across jumpers JU, JU9, and JU0. 5) Connect a +5V power supply to the VCC pad. Connect the power-supply ground to the GND pad. Component List (continued) JU, JU5, JU7, JU8 4 -pin headers JU 5-pin header JU4 4-pin header None Shunts None MAX406/7 PC board Component Suppliers SUPPLIER PHONE FAX WEBSITE IRC Murata Taiyo Yuden TDK Vishay Note: Indicate that you are using the MAX406/MAX407 when contacting these suppliers. 6) Connect a 00µA current source to the LOGIIN pad. 7) Turn on the power supply and verify the output voltages LOGV = 0.75V and LOGV =.00V. Note: For dual-supply operation, JU should be open. Reset the V CC and V DD to within operation range. Detailed Description Jumper Selection Jumper JU controls the REFISET pin of the MAX406/ MAX407 device. See Table for JU function. Table. JU Function JU SHUNT Pins and Pins and REFERENCE CURRENT 0nA 00nA Pins and 4 µa Pins and 5 0µA Note: Make sure a shunt is across pins and of JU8 when using the on-board reference current source.

3 MAX406 Evaluation Kit Table. Setting Output Scale Factor for MAX406 (Single-Supply Operation) SCALE FACTOR (V/decade) JU SHUNT JU4 SHUNT The EV kit incorporates jumpers JU and JU4 JU7 to set the output scale factor. See Tables and for setting the output scale factor for the MAX406 and MAX407. Jumper JU8 controls the REFIIN pin of the MAX406/ MAX407 device. See Table 4 for JU8 function. The EV kit incorporates jumper JU to create a connection between CMVIN and CMVOUT pins. To set the common-mode voltage input to a voltage other than 0.5V (MAX406) or 0V (MAX407), remove the shunt across JU, and then connect a desired commonmode voltage on the CMVIN pad. Output Offset (MAX406) To adjust the output offset voltage for single-supply operation, cut open the short on R4, install a resistor on the R4 pads, and then apply a current on the pad. The value of R4 can be calculated by the following equation: R4 = V OS / I where V OS is the desired offset voltage, and I is a user-supplied offset current. JU5 SHUNT JU6 SHUNT JU7 SHUNT 0.5 Not installed Pins and Pins and Installed Pins and Not installed Pins and Pins and Installed Pins and 0.50 Not installed Pins and Pins and Installed Pins and 0.75 Not installed Pins and Pins and Installed Pins and.00 Not installed Pins and 4 Pins and Installed Pins and.5 Not installed Pins and 4 Pins and Installed Pins and Table. Setting Output Scale Factor for MAX406 (Dual-Supply Operation)/MAX407 SCALE FACTOR (V/decade) 0.5 JU SHUNT JU4 SHUNT JU5 SHUNT JU6 SHUNT JU7 SHUNT Pins and Pins and Pins and Not Installed Pins and Pins and Pins and Pins and Not Installed Pins and 0.50 Pins and Pins and Pins and Not Installed Pins and 0.75 Pins and Pins and 4 Pins and Not Installed Pins and.00 Pins and Pins and 4 Pins and Not Installed Pins and Evaluating the MAX407 To evaluate the MAX407 with the MAX406 EV kit, replace the MAX406ETE with a MAX407ETE, replace R, R, C7, and C8 with component values 0Ω, 0Ω, pf, and pf, respectively. Jumper JU must be open to ensure proper operation with dual supplies. Table 4. JU8 Function JU8 SHUNT Pins and Pins and REFIIN PIN REFIIN is connected to the REFIIN pad, requiring an external reference source. REFIIN is connected to the REFIOUT pad, using the internal reference current source. Evaluates: MAX406/MAX407

4 MAX406 Evaluation Kit Evaluates: MAX406/MAX407 Evaluating the MAX407 (Dual-Supply Operation) ) Verify that there is no shunt across jumpers JU, JU9, and JU0 (dual-supply operation). ) Verify that there is a shunt across JU (sets CMVIN = CMVOUT). ) Verify that shunts are connected across jumpers JU (pins and ), JU4 (pins and 4), JU5 (pins and ), and JU7 (pins and ); and JU6 is open (sets output scale factor K = V/decade). 4) Verify that shunts are connected across jumpers JU8 (pins and ) and JU (pins and ) (sets onboard reference current = 00nA). 5) Connect a +5V power supply to the VCC pad. Connect the power-supply ground to the GND pad. Connect a -5V power supply to the VEE pad. 6) Connect a 00µA current source to the LOGIIN pad. 7) Turn on the power supply and verify the output voltages LOGV = -0.75V and LOGV =.00V. Output Offset Adjustment (MAX407) The MAX407 accepts a large output-offset voltage adjustment at the inverting configuration. To adjust the output offset voltage, install a resistor on R and potentiometer on R4 pads, and make sure there is a shunt across JU (pins and ). The magnitude of the offset voltage is given by the following equation: V OS = REFOUT x (R4 / (R + R4)) x ( + R COMB / R6) where V OS is the desired offset voltage, and R COMB is the effective resistance between the LOGV and SCALE pins. 4

5 MAX406 Evaluation Kit VBIAS LOGIIN GND CMVIN REFVOUT SMA R R4 D PHOTODIODE J C7 00pF R 00Ω % C5 0.µF C6 0.µF JU JU9 JU LOGIIN N.C. N.C. VCC GND VEE CMVIN CMVOUT REFVOUT C 0µF 6V C 0.µF 5V JU C 0µF 6.V C4 0.µF 5V 0 4 V CC GND V EE U MAX406 LOGV SCALE LOGV REFIOUT REFIIN REFISET JU8 C8 00pF R 00Ω % LOGV LOGV JU4 REFIOUT 4 J D PHOTODIODE SMA R5 0.kΩ 0.% R7 0kΩ 0.% JU7 R6 0kΩ 0.% JU5 JU0 R4 (PC TRACE) SHORT VBIAS REFIIN GND JU6 R8 0kΩ 0.% SCALE R9 0kΩ 0.% Evaluates: MAX406/MAX407 R 4.99kΩ JU 5 4 R 49.9kΩ R 499kΩ R0 4.99MΩ Figure. MAX406 EV Kit Schematic 5

6 MAX406 Evaluation Kit Evaluates: MAX406/MAX407 Figure. MAX406 EV Kit Component Placement Guide Component Side Figure. MAX406 EV Kit PC Board Layout Component Side Figure 4. MAX406 EV Kit PC Board 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. 6 Maxim Integrated Products, 0 San Gabriel Drive, Sunnyvale, CA Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.