LTC6421-20 Dual Matched 1.3GHz Differential Ampli ers/ADC Drivers FEATURES DESCRIPTION n Matched Gain 0.1dB The LTC 6421-20 is a dual high speed differential ampli er n Matched Phase 0.2 at 100MHz targeted at processing signals from DC to 140MHz. The n Channel Separation 80dB at 100MHz part has been speci cally designed to drive 12-, 14- and n 1.3GHz 3dB Bandwidth Fixed Gain of 10V/V (20dB) 16-bit ADCs with low noise and low distortion, but can also n IMD = 76dBc at 100MHz, 2V be used as a general-purpose broadband gain block. 3 P-P n Equivalent OIP = 42dBm at 100MHz 3 The LTC6421-20 is easy to use, with minimal support n 1nV/Hz Internal Op Amp Noise circuitry required. The output common mode voltage n 6.2dB Noise Figure is set using an external pin, independent of the inputs, n Differential Inputs and Outputs which eliminates the need for transformers or AC-coupling n Rail-to-Rail Output Swing capacitors in many applications. The gain is internally n 40mA Supply Current (120mW) per Ampli er xed at 20dB (10V/V). n 1V to 1.6V Output Common Mode Voltage, Adjustable The LTC6421-20 saves space and power compared to n DC- or AC-Coupled Operation alternative solutions using IF gain blocks and transformers. n 20-Lead 3mm 4mm 0.75mm QFN Package The LTC6421-20 is packaged in a compact 20-lead 3mm 4mm QFN package and operates over the 40C APPLICATIONS to 85C temperature range. n Differential ADC Driver L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. n Single Ended to Differential Conversion n IF Sampling (Diversity) Receivers n Broadband I/Q Ampli ers n Satellite Communications TYPICAL APPLICATION Matched Dual Ampli ers with Output Common Mode Biasing 3V 1000pF 0.1F V OCMA Distribution of Gain Match + V A V ENABLEA OCMA Z = 200 IN LTC6421-20 40 1000 0.1F 100 12.5 INA +OUTA 35 V OCMA 30 V INA 0.1F 100 12.5 +INA OUTA 25 V OCMA 20 1000 V V 0.1dB GAIN MATCHING 0.1 PHASE MATCHING 15 AT 100MHz 1000 0.1F 10 100 12.5 +INB OUTB V OCMB 5 V INB 0.1F 100 12.5 0 INB +OUTB V 0.25 0.15 0.05 0.05 0.15 0.25 OCMB CHANNEL-TO-CHANNEL GAIN MATCH (dB) 1000 Z = 200 IN 642120 TA01b + V B V ENABLEB OCMB 642120 TA01a 1000pF 0.1F V OCMB 3V 642120fb 1 PERCENTAGE OF UNITSLTC6421-20 ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION (Note 1) + Supply Voltage (V V ) ......................................... 3.6V TOP VIEW Input Current (Note 2) ..........................................10mA Operating Temperature Range (Note 3)....40C to 85C Speci ed Temperature Range (Note 4) ....40C to 85C 20 19 18 17 Storage Temperature Range ...................65C to 150C +INA 1 16 OUTA Maximum Junction Temperature........................... 150C + INA 2 15 V A Output Short-Circuit Duration .......................... Inde nite V 3 14 V 21 V V 4 13 V + V B INB 5 12 +INB 6 11 OUTB 7 8 9 10 UDC PACKAGE 20-LEAD (3mm 4mm) PLASTIC QFN T = 150C, = 43C/W, = 5C/W JMAX JA JC EXPOSED PAD (PIN 21) IS V , MUST BE SOLDERED TO PCB ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION SPECIFIED TEMPERATURE RANGE LTC6421CUDC-20 PBF LTC6421CUDC-20 TRPBF LDDN 0C to 70C 20-Lead (3mm 4mm) Plastic QFN LTC6421IUDC-20 PBF LTC6421IUDC-20 TRPBF LDDN 20-Lead (3mm 4mm) Plastic QFN 40C to 85C Consult LTC Marketing for parts speci ed with wider operating temperature ranges. *The temperature grade is identi ed by a label on the shipping container. Consult LTC Marketing for information on non-standard lead based nish parts. For more information on lead free part marking, go to: