In-Depth Analysis of BM2P0161-Z High-Performance AC/DC Converter
1. One-Sentence Description
The BM2P0161-Z is a PWM-type AC/DC converter integrated with a 730V startup circuit and switching MOSFET, specially designed for low-power appliances. It supports isolated/non-isolated topologies and features high efficiency and wide voltage adaptability.
2. Core Features
- Full-Mode Control: Adopts PWM current-mode control, supporting frequency skipping (125Hz), burst operation (reducing power under light load), and frequency regulation (65kHz typical value) to optimize efficiency and EMI.
- Multiple Protection Mechanisms: Integrates VCC under-voltage/over-voltage protection, SOURCE pin open/short circuit protection, soft start, over-current protection (with AC voltage compensation), and thermal shutdown functions.
- Flexible Design: Externally adjustable current detection resistor and FB pin feedback regulation adapt to various output specifications; built-in 730V high-voltage MOSFET reduces the number of peripheral components.
- Low-Power Optimization: Intelligent charging management for the VCC pin, light-load burst mode, and frequency reduction function achieve standby power consumption below 3mW (at 240V input).
3. Core Technical Specifications
| Parameter | Typical Value/Range | Remarks |
| Input Voltage | 8.9V–26V (VCC) | Supports wide voltage input |
| Output Withstand Voltage | 730V (DRAIN) | Maximum withstand pulse voltage 730V |
| Quiescent Current | 0.65mA (Typ) | Low standby power consumption |
| Switching Frequency | 65kHz (Typ) | Adjustable via FADJ pin |
| Efficiency | >85% (typical load) | Optimized core loss and conduction loss |
| Operating Temperature | -40℃–+105℃ | Adapts to harsh environments |
4. The Story Behind the Chip
The BM2P0161-Z was developed amid the industry trend of home appliance intelligence and energy efficiency upgrades. Aiming at the pain points of traditional AC/DC converters, such as high standby power consumption, severe EMI interference, and complex design, ROHM solves these issues through the following innovations:
- 730V Startup Circuit: Replaces traditional discrete solutions, shortens startup time (<0.1s@10μF), and reduces standby energy consumption.
- Integrated Design: Packages MOSFET, control logic, and protection modules into one, reducing the number of peripheral components (only a few resistors and capacitors are needed).
- Patented Protection Technology: LEB (Leading Edge Blanking) blanking technology eliminates switching transient interference, and the VSOURCE compensation algorithm improves over-current protection accuracy.
5. Design Philosophy
The BM2P0161-Z adheres to the trinity philosophy of “high reliability × simple design × green energy saving”:
- Reliability: Withstands HBM ESD 4kV protection, thermal shutdown (TSD), and other multiple protections, suitable for industrial-grade applications.
- Simplicity: Provides detailed reference circuits (such as Flyback typical application Figure 15) and supports DIP7K/DIP7WF dual packages for fast layout.
- Environmental Protection: Frequency skipping function reduces EMI radiation, meeting international energy efficiency standards (such as CoC Tier2).
6. Application Scenarios
Widely used in low-power consumer and industrial devices:
- Home Appliances: Air conditioner remote controls, air purifiers, power modules for IH rice cookers.
- Consumer Electronics: Mobile phone/tablet chargers, Bluetooth speaker adapters.
- Industrial Control: Sensor power supply units, auxiliary power supplies for smart meters.
7. Unique Advantages
- Ultra-Low Standby Power Consumption: Achieves industry-leading standby energy consumption at the 0.3mW level through VCC charging management and burst mode.
- Wide Voltage Tolerance: The DRAIN terminal withstands 730V transient high voltage (10μs pulse), avoiding damage from lightning surges.
- Debugging Friendliness: Provides detailed protection timing diagrams (Figure 4) and PCB thermal design guidelines (Figure 14) to shorten the R&D cycle.
8. What Engineers Must Know When Selecting
- Absolute Maximum Ratings: VCC must not exceed 32V, and the DRAIN pulse current must be below 12A (BM2P0161-Z).
- Key Thermal Design: The recommended single-layer PCB heat dissipation area is ≥74.2mm×74.2mm, and derating is required in high-temperature environments.
- Protection Mechanism Linkage: After protection is triggered due to abnormal FB pin voltage (>VFOLP1A for 128ms), a 332ms reset is required.
Package Compatibility: The DIP7WF version supports wave soldering; pay attention to the pin pitch (2.54mm) and thermal pad design.
Conclusion: The BM2P0161-Z is an ideal choice for low-power AC/DC conversion due to its high integration, ultra-low power consumption, and strong adaptability. Engineers can fully leverage its performance advantages through precise parameter matching (such as setting the frequency skip amplitude via CFADJ) and rigorous thermal design.
Contact:
Sylvia Xu | ECSource Components Co.,Limited
Top 10 Test Laboratory Distributors in Asia.
D-U-N-S Number:655918890 | ISO90001 Certificated Company
Phone/Whatsapp: 0086-19806586673
Email:sylvia@ecsource.net
Line Card : FPGA, RF, MEMORY,CONNECTOR,Power
