Powering tests with the PP2 regulator

Laura GonellaPhysikalisches Institut Uni Bonn

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PP2 regulators´ setup

Controller board

Regulator board

Type 2 cables with sense lines connected at the end of the cable

Labview interface

Canbus supply

Controller supply

Regulator supply

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Setting the voltage at the end of the Type2 cables (1)

• Via the labview interface it is possible to set the voltage desired at the end of the Type 2 cables– The regulators use the measurement done via the sense lines to

adjust their outputs, according to the load current, to keep this value constant

• The setting of the desired voltage at the end of the Type 2 cables is done by adjusting the regulator´s potentiometer– 1.23V – 2.17V– At start up the value of the potentiometer is not predictable

• Before powering the regulator board give a KILL command to disable all the regulators outputs

• Then power the board, move the potentiometer of the powered channel to -99

• In this way the voltage at the output of the regulator is 1.23V (minimum achievable value) after UNKILL

– The cursor in the program allows to chage the potentiometer value with respect to its current position. Example:

• 1.231V → +10 → 1.290V, ΔV = 0.059V• 1.490V → +10 → 1.591V, ΔV = 0.101V

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Setting the voltage at the end of the Type2 cables (2)

– The regulation is not linear. Example:• 1.231V → +10 → 1.289V, ΔV = 0.051V• 1.231V → +20 → 1.359V, ΔV = 0.128V • 1.231V → +30 → 1.421V, ΔV = 0.190V

– To know what value is set the best way is to measure it directly at the end of the cable

• It is also done by the software but this does not give a precise value– An ADC on the regulator board reads the sensed voltage– In the experiment this is read out by the DCS which contains the calibration

curve of the ADC– In this setup the ADC is read by the controller which does not store the

calibration curve but has only a few points

• The measurement of the regulator output can be done on the connector at the beginning of the Type 2 cable

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Power configuration with regulators

PP2 regulators´ setup

Type2 cables

Vreg Vsense Vin1 Vin2 VDDA VDDD

1.8V

I1 I2

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Measured at the pad

Measured across R=10mΩ

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Voltages and currents

Vreg (V)

Vsense (V)

Vin1 (V)

Vin2 (V)

VDDA (V) VDDD (V)

I1 (A) I2 (A)

Power up 2.297 1.808 1.782 1.783 1.509 1.194 0.150 0.140

Clock on 2.345 1.806 1.782 1.784 1.506 1.189 0.180 0.150

Std cfg 2.623 1.807 1.748 1.783 1.454 1.184 0.380 0.150

PrmpVbp*2

2.818 1.804 1.720 1.780 1.419 1.176 0.510 0.150

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Threshold scan

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Threshold scan – PrmbVbp*2

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PP2 regulator vs commercial supply

PP2 regulator + Type2 cables

Commercial supply

Std PrmpVbp*2 Std PrmpVbp*2

Vth 4618 4626 4499 4466

Vth dispersion 588 572.6 599.4 588

Noise 150.6 144.1 152.2 142.3

Noise dispersion 14.11 12.48 16.26 13.45

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• Comparison of threshold and noise values for this powering configuration with power from the PP2 regulators and with a commercial supply (shown 2 weeks ago)