54A0059_V1.1_EN / LeddarSteer DBSD Evaluation Board
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User Guide
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Table 7: Waveform parameters
Parameter
Value
Maximum number of controllable waveforms per DBSD
8
Frequency
1 kHz to 5 kHz (2 kHz typ.)
Duty cycle
50% high, 50% low
Min AC amplitude (peak-to-peak)
2 V
Max AC amplitude (peak-to-peak)
40 V
Average AC voltage target
≤20
mV
Magnitude discretization
@ low voltage (1 V)
@ high voltage (20 V)
≤10
mV
≤200
mV
Single LC cell (1.5 µm thick design)
Capacitance
Resistance
240 nF
>4
MΩ
-20 V
200 µs -1 ms
Avg
mV
-1 V
+1 V
+20 V
High drive
Low drive
2 Vpp
40 Vpp
Fig. 2: Single-waveform example
3.5.
Transition Time
The transition time represents the time to change from a deflection angle to another.
Fast transition time will occur from low to high voltage LC cell drive. Fast transition time is between 20 µs
and 100 µs, and will be lower than 60 µs for temperatures above 30 °C.
Slow transition time (also referred to as “relaxation time”) will occur from high to low voltage LC cell drive.
The DBSD internal temperature will impact the slow transition time. Above a DBSD internal temperature of
60°C, the slow transition time is lower than or equal to 750 µs.
Therefore, the DBSD needs to be heated to achieve optimal temperature using ITO layers.
