ROHM Semiconductor, headquartered in Kyoto, Japan, has developed a new series of PWM-controlled FET-external universal controller ICs, tailored for industrial AC-DC power supplies. The company has launched four new products in production, including the "BD28C55FJ-LB" for low-voltage MOSFETs, "BD28C54FJ-LB" for medium-to-high-voltage MOSFETs, "BD28C57LFJ-LB" for IGBT drivers, and "BD28C57HFJ-LB" for SiC MOSFETs.
Despite the gradual alleviation of the global semiconductor shortage, the demand for industrial power supply products remains high, with AC-DC controller ICs particularly scarce due to limited manufacturers. ROHM’s new PWM-controlled AC-DC controller ICs address this supply gap by meeting the high packaging and performance demands of industrial applications.
The new products feature an input voltage range of 6.9V to 28.0V, a maximum circuit current of 2.0mA, and a maximum startup current of 75μA. They have a maximum duty cycle of 50% and come in a standard SOP-J8 package, compatible with commonly used industrial power supply components, which helps shorten design cycles. All models support undervoltage lockout (UVLO) with a hysteresis function, providing improved reliability with a threshold voltage deviation of just ±5%, compared to the ±10% deviation of conventional products.
Additionally, the new products are designed for long-term supply stability, supporting the continuous operation of long-lifetime industrial equipment. Production began in July 2024 with an initial output of 100,000 units per month, and they are available for purchase on the e-commerce platform Ameya360.
Future plans include expanding the product line to support high-voltage MOSFETs and GaN devices, as well as introducing products with a 100% maximum duty cycle.
Application Examples:
- Industrial Equipment: AC-DC power supplies, motor drive inverters, and other power supply applications.
E-Commerce Sales Information:
- Start Date: July 2024
- Platform: Ameya360 (with plans for additional e-commerce platforms)
Product Models:
- BD28C54FJ-LB
- BD28C55FJ-LB
- BD28C57HFJ-LB
- BD28C57LFJ-LB
Terminology:
1. PWM Control Method
PWM (Pulse Width Modulation) is a semiconductor power control method that adjusts the output power by varying the ratio of on-time to off-time within a fixed period.
2. Duty Cycle
The ratio of the time a pulse is in the on state to the total cycle time. It is expressed as a percentage and calculated as Pulse Width (t) ÷ Period (T).
3. Hysteresis-Type Self-Recovering Undervoltage Lockout (UVLO)
UVLO (Under Voltage Lock Out) stops the IC operation when input voltage drops below a threshold, preventing abnormal circuit conditions. A hysteresis-type UVLO provides a voltage range for stable operation during start-up and shutdown, improving reliability.