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PIN Diode and Low Gain Silicium Detector Read-Out Chip


  • TRL Technology Readiness Level 8 – Full system using ASIC running
  • Detector Read-Out Si PIN Diodes
  • Number of Channel 64
  • Signal Polarity Positive
  • Sensitivity Trigger on 0.2fC
  • Test Board available for 64 channels


SKIROC 2A is a 64-channel front-end ASIC designed to readout silicon PIN diodes. Each channel is made of a variable-gain and low-noise charge preamplifier followed by two shapers – one with a gain of 1 and the other with a gain of 10 – to provide a charge measurement from 0.2 fC up to 10 pC. A time tagging is performed by a 12-bit TDC ramp. The charges and times are stored in a 15-depth Switched Capacitor Arrays (SCA), the values of which are converted by a multi-channel 12-bit Wilkinson ADC and sent to an integrated 4 Kbytes memory. The analog value of the charge is also available on an output pin. The trigger chain is composed of a high gain fast shaper and a discriminator and allows each channel to auto trigger down to 0.2 fC. Thresholds of the 64 discriminators are set by a common 10-bit DAC and an individual 4-bit DAC per channel. Each discriminator output is sent to an 8-bit delay cell (delay time tunable between 100 ns and 300 ns) to provide the Hold signal for the SCA cells of the slow channel. The power consumption is 6.2 mW/channel and each stage can be individually shut down when not used.

Technical Specifications

Detector Read-Out

Si PIN Diodes

Number of Channels


Signal Polarity



Trigger on 0.2fC

Timing Resolution


Dynamic Range

10 pC, Integral Non Linearity <1%

Packaging & Dimension

BGA 400 (17x17mm)

Power Consumption

6.2 mW /ch, power supply: 3.3V
power pulsing


64 current inputs


1 multiplexed analog charge output
12-bit charge and time measurement
Trigger 0R of the 64 discriminators

Internal Programmable Features

Common gain adjustment for the input, common trigger threshold adjustment (10
bits) and individual threshold (4 b), 12-bit charge and time measurement, 64 trigger
masks, multiplexed analog output


Compare with Weeroc chip.


Ordering Options

Code Description
WWSKIROC2ABA SKIROC 2A - PIN diode and low gain silicium detector read out chip - BGA (Ball Grid Array)