Abstract: A thermal imaging device (10) has single integrated circuit chip (86) to perform various analog signal processing (ASP) functions. The imaging device (10) has a detector array (50) including a plurality of detectors (50') each of which generate an electrical signal (78) indicative of the infrared flux incident thereon. These electrical signals (78) are processed and provided in the form of serial analog video signals (52) to the ASP chip (86). The ASP chip (86) includes circuitry (200) for correcting for the differing responsivity of serial manufactured detector arrays (50), circuitry (202) for correcting the gain of the serial analog signal (52) globally, and circuitry (206) for sensing the gain of a processing serial analog signal (90) which the ASP chip (86) provides to an analog-to-digital (A/D) converter (92) of the thermal imaging device (10).