PoCL Device Detector
Each PoCL controller implements a PoCL device detector.
The detector measures the input impedance of the camera power input circuit at the off state and check if it is within the specified limits specified for PoCL camera Link cameras.
Therefore, a calibrated sense current is injected by the frame grabber into the power input circuit of the camera through the camera cable. After the expiration of the "sense time delay" time interval that allows the input capacitance to be charged, the detector measures repetitively the voltage during the "Sense OK time". If the voltage stays between the thresholds, the power is applied.
The camera must deliver a clock within the "initial clock turn-on delay" after the application of the power. If this is not the case, the frame grabber turns off the power immediately.
While the camera is powered, the PoCL device detector monitors continuously the Camera Link clock. If this clock is interrupted during at least "turn-off delay after clock loss" time interval, the power is immediately turned off.
PoCL device detector characteristics
Parameter |
Min |
Typ |
Max |
Units |
Sense current on 10K impedance load |
30 |
52 |
75 |
ľA |
Detector thresholds |
0.3 |
|
1.2 |
V |
Allowable impedance range |
8 |
10 |
12 |
kΩ |
PoCL camera detector sense time delay |
|
500 |
|
ms |
PoCL camera detector sense OK time |
|
500 |
|
ms |
Initial clock turn-on delay |
|
500 |
|
ms |
Turn-off delay after clock-loss |
|
500 |
|
ms |