| Junction ambient i) | RthjA | 275 | K/W |
| Junction - soldering point | RthjS | "140 |
| | | |
INPUT CONNECTIONS AND CALIBRATION The high (10 Ml ) input impedance of the AD679 eases the task ofinterfacing to high source impedances or multiplexer channel-to-channel mismatches of up t0 300 I . The 10 V p-p full-scale input range accepts the majority of signal voltages without the need for voltage divider networks which could dete- riorate the accuracy of the ADC. The AD679 is factory trimmed to minimize offset, gain and lin- earity errors. In unipolar mode, the only external component that is required is a 50 I +1% resistor. Two resistors are re- quired in bipolar mode. If offset and gain are not critical (as in some ac applications), even these components can be eliminated. In some applications, offset and gain errors need to be trimmed out completely. The following sections describe the correct pro- cedure for these various situations.
