LTC2063/LTC2064/LTC2065 APPLICATIONS INFORMATION HEAT SOURCE/ # RF POWER DISSIPATOR MATCHING RELAY NC RG** ‡ – + VIN THERMAL VTHERMAL GRADIENT +IN OUT R § L LTC2063 † – + RG –IN VTHERMAL R § F RELAY ** * # 2063 F04 * CUT SLOTS IN PCB FOR THERMAL ISOLATION. ** INTRODUCE DUMMY JUNCTIONS AND COMPONENTS TO OFFSET UNAVOIDABLE JUNCTIONS OR CANCEL THERMAL EMFs. † ALIGN INPUTS SYMMETRICALLY WITH RESPECT TO THERMAL GRADIENTS. ‡ INTRODUCE DUMMY TRACES AND COMPONENTS FOR SYMMETRICAL THERMAL HEAT SINKING. § LOADS AND FEEDBACK CAN DISSIPATE POWER AND GENERATE THERMAL GRADIENTS. BE AWARE OF THEIR THERMAL EFFECTS. # COVER CIRCUIT TO PREVENT AIR CURRENTS FROM CREATING THERMAL GRADIENTS. Figure 4. Techniques for Minimizing Thermocouple-Induced Errors NO SOLDER MASK GUARD OVER GUARD RING RING LEAKAGE CURRENT VBIAS ‡ +IN –IN HIGH-Z SENSOR V– V– R § F OUT V+ VOUT V+ ‡ NO LEAKAGE CURRENT, V–IN = V+IN § AVOID DISSIPATING SIGNIFICANT AMOUNTS OF POWER IN THIS RESISTOR. IT WILL GENERATE THERMAL GRADIENTS WITH RESPECT TO THE INPUT PINS AND LEAD TO THERMOCOUPLE-INDUCED ERROR. THERMALLY ISOLATE OR ALIGN WITH INPUTS IF RESISTOR WILL CAUSE HEATING. GUARD RING RF V HIGH-Z SENSOR BIAS V+ VIN R – + IN – LEAKAGE LTC2063 VOUT CURRENT + V– LEAKAGE CURRENT IS ABSORBED BY GROUND INSTEAD OF 2063 F05 CAUSING A MEASUREMENT ERROR. Figure 5. Example Layout of Inverting Amplifier with Leakage Guard Ring Rev. C For more information www.analog.com 17 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Applications Information Typical Applications Package Description Revision History Typical Application Related Parts