TIDT351
September 2023
1
Description
Features
Applications
1
Test Prerequisites
1.1
Voltage and Current Requirements
1.2
Considerations
1.3
Dimensions
2
Testing and Results
2.1
Efficiency and Loss Graph
2.1.1
Efficiency
2.1.2
Loss
2.2
Load Regulation
2.2.1
18-V Output Voltage (VOUT-A)
2.2.2
12-V Output Voltage (VOUT-B)
2.3
Line Regulation
2.3.1
18-V Output Voltage (VOUT-A)
2.3.2
12-V Output Voltage (VOUT-B)
2.3.3
Efficiency and Loss vs Line Variation
2.4
Cross Regulation
2.4.1
12-V Output With No Load
2.4.1.1
Effects on the 18-V Output
2.4.1.2
Effects on the 12-V Output
2.4.2
18-V Output With no Load
2.4.2.1
Effects on the 12-V Output Voltage
2.4.2.2
Effects on the 18-V Output Voltage
2.5
Thermal Images
3
Waveforms
3.1
Switching
3.1.1
Primary Switching Node
3.1.1.1
8-V Input Voltage
3.1.1.1.1
Full Load
3.1.1.1.2
No Load
3.1.1.2
36-V Input Voltage
3.1.1.2.1
Full Load
3.1.1.2.2
No Load
3.1.2
Diode D3 Referenced to VOUT-B (12 V)
3.1.2.1
8-V Input Voltage
3.1.2.1.1
Full Load
3.1.2.1.2
No Load
3.1.2.2
36-V Input Voltage
3.1.2.2.1
Full Load
3.1.2.2.2
No Load
3.1.3
Diode D4 Referenced to VOUT-A (18 V)
3.1.3.1
8-V Input Voltage
3.1.3.1.1
Full Load
3.1.3.1.2
No Load
3.1.3.2
36-V Input Voltage
3.1.3.2.1
Full Load
3.1.3.2.2
No Load
3.2
Input Voltage Ripple
3.3
Output Voltage Ripple
3.3.1
VOUT-A (18 V)
3.3.2
VOUT-B (12 V)
3.4
Load Transients
3.4.1
Switching on VOUT-A (18 V)
3.4.1.1
Effects on VOUT-A
3.4.1.2
Effects on VOUT-B
3.4.2
Switching on VOUT-B (12 V)
3.4.2.1
Effects on VOUT-B
3.4.2.2
Effects on VOUT-A
3.5
Start-Up Sequence
3.5.1
Full Load
3.5.2
No Load
3.6
Shutdown Sequence
3.1.2
Diode D3 Referenced to VOUT-B (12 V)