The power consumption for radhard chips was measured for board 5 and board 6. For board 5 the measurements were done before and after irradiation. The power wasn't measured directly because the terminating resistors for the clock and command lines and an extra chip for the test pattern enable line are located on the test board.
For Vdd = 5V about 135 mA is used by the termination resistors (130 mA) and the test pattern driver (5 mA).
The following figure shows the current (Vdd = 5V) versus the clock frequency. The current was measured with 1) only the clock running and 2) sending a command sequence to keep the ship busy (reset, write register, sent trigger, read event).
Comments:
No irradiation: switching the chips on without supplying the clock results in a not stable current draw. The range between the lowest value and the highest value is about 10 mA. After the clock is switched on the current is stable at the lower value. If the chip is active the current draw increases and is higher than just supplying power or power and clock.
Irradiated chips: There are two lines shown for the irradiated board (bd5) for the case when only the clock is provided. The difference between both curves is 20 mA and our experience shows that the high current curve occures most of the times. Switching on the chip without supplying a clock and command it goes useally in a high current state (~80mA) and providing the clock doesn't change anything. If the chip is active the current goes down, but increases when the chip is idle again.