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In-panel Amp Circuit Diagram

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In-panel Longevity Features

• Amplifier circuit borrowed from L3 with added longevity features:– Resettable polyfuses on power lines.

– Diode protection to allow continued operation after one readout channel LSTs dies.

– Diode clamps on power line to prevent reverse-bias damage.

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In-panel Longevity Features - cont.

• HV distribution also incorporates longevity features:– 400 M current limiting resistors on every

channel to allow continued HV operation even with multiple LST failures.

– Encapsulation in silicone conformal coating for protection from humidity, dust.

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In-panel Segregation

• Multiple HV chains matching gas distribution chains:– LST planes completely segregated into different

gas/HV chains.

– Each plane further subdivided into gas/HV chains with roughly 24 LSTs.

• Multiple power chains matching gas/HV chains.– LST planes are connected in the power chains through

the amplifier circuit.

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In-panel Amps

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In-panel Amps