TEST REPORT
Four Output Flyback Bias Converter Reference Design for Inverter and Motor Drive Applications
1 Description
This isolated primary regulated flyback converter provides a total of eight output voltages. These outputs consist of four isolated pairs of +18-V and –5.1-V outputs, with three pairs capable of 25 mA maximum for and one capable of 75 mA maximum. These outputs are designed to be used as an IGBT driver bias supply for a total of six IGBTs (25 mA for three high-side drivers and 75 mA for three low-side drivers). It operates over an input voltage range of 7 V–32 V in a compact form factor with a single transformer.
Figure 1-1 Top of PCB
Figure 1-2 Bottom of PCB2 Test Prerequisites
2.1 Voltage and Current Requirements
Table 2-1 Voltage and Current Requirements
| Parameter | Specifications |
|---|---|
| Input voltage range | 7 V–32 V |
| Output voltage and current |
+18 V and –5.1 V, 75 mA (3X) +18 V and –5.1 V, 25 mA |
| Switching frequency | 400 kHz |
| Isolation | 2600 VAC (NP, NF-NS), 1300 VAC (coil-coil) |
2.2 Required Equipment
- Four loads (2 W each)
- Power supply capable of 50 V and 1 A
- Oscilloscope and probes
- Digital multimeters
- Stability measurement device (Venable or Bode100)
