BeetleFE 1.0

BeetleFE 1.0 is the first prototype chip for the preamplifier/shaper circuitry of the Beetle chip.

It contains three different sets of preamplifier shapers (4 channels each variation) that follow the basic RD20 approach of a folded cascode charge sensitive preamplifer followed by an active CR-RC shaper and a buffer.

The three sets differ as follows

• Set 1 and 2 use PMOS input transistors but differ in the feedback network of the shaper.
• Set 4 (set 3 was omitted at a late stage) uses a NMOS input transistor.

The picture shows the layout of the chip. The three groups of each four channels of F/E sets are (from top to bottom) 1, 2 and 4.