SNVAA88 December   2023 LM51581-Q1 , TPS1H000-Q1 , TPS92642-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2System Description
    1. 2.1 Dual Cable Concept
    2. 2.2 Single Cable Concept
  6. 3Camera Module Design with Single Coaxial Cable Connection
    1. 3.1 Power-Over-Coax Filter
    2. 3.2 Boost Converter
    3. 3.3 High-Side Switch
    4. 3.4 Buffer Capacitor
    5. 3.5 LED Driver
    6. 3.6 Serializer
    7. 3.7 Design Steps
  7. 4Test Results
    1. 4.1 LED and PoC Voltage Waveforms
    2. 4.2 Margin Analysis Program Result
    3. 4.3 Differential Supply Noise Level
    4. 4.4 Test Cases
  8. 5Summary
  9. 6References

Test Cases

Table 4-1 shows the test cases with different test parameters such as LED pulse duration and frequency, LED peak power, PoC voltage and high-side switch current limit. All shown test cases have passed the MAP test with negligible impact. The boost converter output voltage for all tests was set to 24 V.

Table 4-1 List of Test Cases

Test case

PoC Voltage(1) (V)

HSS Current Limit (mA)

Capacitor Size (μF)

LED Peak Current (A)

LED Peak Power(2) (W)

LED Pulse Width (ms)

LED Pulse Frequency (Hz)

1

12

400

560

3

18

4

30

2

12

200

330

3

18

3

30

3

12

200

330

3

18

2

60

4

12

100

220

3

18

3

30

5

9

200

330

3

18

2

60

6

12

250

330

2.5

15

4

60

7

8

250

330

2.5

15

4

60

PoC voltage value indicates the voltage level on the ECU side and does not consider the voltage drop across the coaxial cable.
All tests have been performed with a LED string configuration of two OSRAM SFH 4728AS A01 IR LEDs connected in series.