4
Interfaces
Page 17 / 39
IMAGO Technologies GmbH
Strassheimer Str. 45; 61169 Friedberg; Germany; Tel. +49(0)6031-6842611
LED Flash Controller
The LED Flash Controller is designed as a current source. Output current, flash duration and other parame-
ters can be set via software.
The following diagram shows the simplified internal structure for the LED Controller:
CPU
Real-Time
Communication
Controller
(FPGA)
Output Channel
Filter
Current
Regulation
Ext. LED
Lighting
Unit
+24V
Current
reference
Strobe
enable
Current
value
LED +
R
Sense
LED -
GND
Power
Supply
VisionCam
Int. LED
ring-light
Figure 3:
LED Controller structure
The software API allows selection between the internal ring-light (optional) and the external connector.
See chapter 4.1 for connector pinout.
When initializing the strobe controller using the API, the user has to specify a load voltage for the given
current value (see
SetLimits()
and
SetFixedCurrent()
). This information is used to protect the
internal circuit against overload by increasing the minimum OFF-time or by limiting the current value. If
there load voltage is not exactly known, lower values should be used because this provides more
protection.
With the internal ring-light, the following load voltages should be used:
Current (mA)
Load voltage (V)
100…499
8
500…999
10
1000
…1499
12
1500…1999
15
2000
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