Reference Design

A system-level evaluation board that combines ROHM's IC and discrete products. We have already solved not only the characteristics of individual products but also the problems that may occur when combining them to build a system, thus contributing significantly to the reduction of development time for our customers.

Non-Isolation Buck Converter PWM method Output 2.6 W 13 V Reference Design


The BM2P139TF-EVK-001 evaluation board outputs 13 V voltage from the input of 90 Vac to 264 Vac. The output current supplies up to 0.2 A. BM2P139TF which is PWM method DC/DC converter IC built-in 650 V MOSFET is used.

The BM2P139TF contributes to low power consumption by built-in a 650 V starting circuit. Built-in current detection resistor realizes compact power supply design.
Current mode control imposes current limitation on every cycle, providing superior performance in bandwidth and transient response.
The switching frequency is 100 kHz in fixed mode. At light load, frequency is reduced and high efficiency is realized. Built-in frequency hopping function contributes to low EMI. Low on-resistance 9.5Ω・650V MOSFET built-in contributes to low power consumption and easy design.


Reference Board NameBM2P139TF-EVK-001
Input Voltage Range90 to 264Vac
Input Frequency47to63Hz
Output Voltage13V(Typ)
Maximum Output Power2.6W Iout=200mA
Output Current Range2 to 200mA*1
Stand-by Power33mW Iout=0A
Output Ripple Voltage34mVpp*2
Operating Temperature-10 to 65deg.C

*1 Please adjust operating time, within any parts surface temperature under 105 °C
*2 Not include spike noise


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