TCD1304 specifications

The TCD1304 exists in two version; the TCD1304AP and the newer RoHS-compliant TCD1304DG. The two versions have identical specifications, and on this site they are collectively referred to as the TCD1304.

The specifications are evident from the datasheet but I’ll draw some key points here:

The spectral response

The TCD1304 is well suited for work within the visible spectrum. g106

The circuit diagram

When inspecting the output from the TCD1304, there’s often a pattern that the even pixels give a slightly higher/lower value than the odd. In the datasheet this is referred to as the register imbalance. Looking at the circuit diagram one could speculate that even and odd pixels are sent to different shift registers.


The dark current

As with all photoelectric devices the TCD1304 has dark current. It’s dependent on integration time and temperature:


For low-signal applications it’s tempting to sum many readings with short integration times as this could keep the total dark current low. However the total transfer efficiency and the CCD’s read-out noise foil such schemes. The general picture is that a 10 s integration gives a better S/N than 2x 5 s integrations.¹


¹ John James: Spectrograph Design Fundamentals