LT1124/LT1125 applicaTions inForMaTion The LT1124 may be inserted directly into OP-270 sock- (5µV/V). However, Table 1 can be used to estimate the ets. The LT1125 plugs into OP-470 sockets. Of course, expected matching performance between the two sides of all standard dual and quad bipolar op amps can also be the LT1124, and between amplifiers A and D, and between replaced by these devices. amplifiers B and C of the LT1125. Matching SpecificationsOffset Voltage and Drift In many applications the performance of a system depends Thermocouple effects, caused by temperature gradients on the matching between two op amps, rather than the across dissimilar metals at the contacts to the input termi- individual characteristics of the two devices. The three op nals, can exceed the inherent drift of the amplifier unless amp instrumentation amplifier configuration shown in this proper care is exercised. Air currents should be minimized, data sheet is an example. Matching characteristics are not package leads should be short, the two input leads should 100% tested on the LT1124/LT1125. be close together and maintained at the same temperature. Some specifications are guaranteed by definition. For The circuit shown in Figure 1 to measure offset voltage example, 70µV maximum offset voltage implies that mis- is also used as the burn-in configuration for the LT1124/ match cannot be more than 140µV. 112dB (= 2.5µV/V) LT1125, with the supply voltages increased to ±16V. CMRR means that worst-case CMRR match is 106dB 50k* 15V – 100Ω* VOUT + 50k* –15V VOUT = 1000VOS *RESISTORS MUST HAVE LOW THERMOELECTRIC POTENTIAL 1124/25 F01 Figure 1. Test Circuit for Offset Voltage andOffset Voltage Drift with TemperatureTable 1. Expected MatchLT1124AC/AMLT1124C/MLT1125AC/AMLT1125C/MPARAMETER50% YIELD98% YIELD50% YIELD98% YIELDUNITS VOS Match, ∆VOS LT1124 20 110 30 130 µV LT1125 30 150 50 180 µV Temperature Coefficient Match 0.35 1.0 0.5 1.5 µV/°C Average Noninverting IB 6 18 7 25 nA Match of Noninverting IB 7 22 8 30 nA CMRR Match 126 115 123 112 dB PSRR Match 127 118 127 114 dB 11245ff 10 For more information www.linear.com/LT1124 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Applications Information Performance Comparison Typical Applications Schematic Diagram Package Description Revision History Typical Application Related Parts