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List of figures

Figure 1.

VN808 and VN340SP reference design boards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Figure 2.

VN808 block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Figure 3.

VN340SP block diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Figure 4.

VN808 reference design board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Figure 5.

Surge Suppression Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Figure 6.

Typical input/status isolation by optocouplers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Figure 7.

Burst pulse affecting one input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Figure 8.

Recommended layout for High Power Dissipation capability . . . . . . . . . . . . . . . . . . . . . . . 12

Figure 9.

DC/DC part of the application circuit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Figure 10.

Current and voltage conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Figure 11.

Complete application circuit with VN808 and L5970D devices. . . . . . . . . . . . . . . . . . . . . . 13

Figure 12.

Switching part of the application circuit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Figure 13.

VN340SP reference design board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Figure 14.

Switching part of the application circuit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Figure 15.

Complete application circuit with VN340SP and L5970D devices . . . . . . . . . . . . . . . . . . . 17

Figure 16.

Description of the switching inductor loads. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Figure 17.

IPS simplified structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Figure 18.

Simplified thermal models. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Figure 19.

Power supply tests (IEC 61000-4-4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Figure 20.

Switch diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Figure 21.

Test on input ports (IEC 61000-4-4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Figure 22.

Output port tests (IEC 61000-4-4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Figure 23.

Power supply tests (IEC 61000-4-5) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Figure 24.

Test on Output Ports (IEC 61000-4-5) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Figure 25.

Power supply tests (IEC 61000-4-6) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Figure 26.

Input port tests (IEC 61000-4-6) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Figure 27.

Output port tests (IEC 61000-4-6) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Figure 28.

VN808 Waveforms (Part 1). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Figure 29.

VN808 Waveforms (Part 2). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Figure 30.

GND_Power disconnection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Figure 31.

Switching lamps: VCC = 24V, f = 0.5 Hz, Wave1 = VINOPT,

Wave2 = VOUT, Wave4 = ICH1OUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Figure 32.

Waveform tOFF inductor load: VCC = 24V, L = 130mH, RLOAD = 63W,

tOFF = 1.2101 ms, Wave2 = VOUT, Wave1 = VINOPT, Wave4 = ICH1OUT . . . . . . . . . . 32

Figure 33.

Waveform switching inductive load: VCC = 24V, L = 130mH, RLOAD = 48W,

f = 0.5Hz, Wave2 = VOUT, Wave1 = VINOPT, Wave4 = ICH1OUT . . . . . . . . . . . . . . . . . 33

Figure 34.

Switching with short circuit: VCC = 24V, f = 0.5Hz, Wave2 = VSTATUSOPT,

Wave1 = VINOPT, Wave4 = ICH1OUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Figure 35.

Time delay between VINOPT and VOUT: VCC = 24V, Load = Lamp,

Wave2 = VOUT, Wave3 = VINOPT, Dt = 58.462 µs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Figure 36.

GND_Power disconnection for VN808: VCC = 25V, Load = Lamp,

Wave1 = VCC, Wave2 = VOUT, Wave3 = GND of power supply . . . . . . . . . . . . . . . . . . . 33

Figure 37.

Waveform ITOT and VINOPT during the test with short circuit VCC = 28V,

TA = 85°C, Wave4 = ITOT, Wave1 = VINOPT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Figure 38.

Waveform on ITOT and VINOPT during the test with short circuit VCC = 28V,

TA = –25°C, Wave4 = ITOT, Wave1 = VINOPT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Figure 39.

Case temperature dependency vs. current ITOT (TA = 25°C and VCC = 24 V) . . . . . . . . 34

Figure 40.

Burst applied on the power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35