DC-DC Controller ICs for 0.1W to 40W Industrial Power ConvertersNovember 10, 2018 by Paul Shepard
MORNSUN recently launched dc-dc power supply control ICs. The targeted power range is from 0.1W to 40W and input voltage range is from 3.3V to 100V. These controllers are expected to be used in the applications of industrial equipment, process control system, data acquisition system, etc.
Secondary-side feedback control ICs, the SCM1101A and SCM1102A, are in a MSOP-8 package. These current-mode pwm controllers are optimized for 5W to 40W dc-dc switching power supply applications. They are suitable for isolated dc-dc converters such as instrument power supplies and communications power.
The maximum operating frequency can be up to 480kHz and is set by external resistors. To conserve energy under light-load conditions, the green mode function continuously decreases the switching frequency, thus enabling the converter to maintain high efficiency over the entire load range. For optimized standby power consumption, the power supply enters into a burst mode under no load conditions.
The typical start-up current of SCM1101A is only about 1uA. To operate with the start-up ICs SCM9603B, a lower start-up voltage threshold can be achieved. SCM1102A minimum chip starting voltage is 4V.
The SCM1201A is a pwm controller IC for power supplies in push-pull topology and integrates a pair of power MOSFET's. It has an ultra-wide input voltage range that allows it to start up and operate normally at a low input voltage of 4.5V and it tolerates high input voltages is up to 40V without damage. It's suitable for 1W and lower power dc-dc switching power supply.
To maximize the reliability, the chip design incorporates three key technologies. The first one consists of a soft start function which avoids the impact of booting up under high current conditions that potentially could harm the device, hence ensuring a normal startup in CC mode.
The second one being an output short-circuit protection with such a good consistency, which will neither be impaired by a deviation in power supply parameters, nor influenced by high or low operating temperature conditions.
Third one is the integrated over temperature protection. If the temperature exceeds the specified range, the controller automatically puts itself into a sleep mode and subsequently self-recovers, once the temperature drops below the set threshold value into a safe operating range.
The three chips are integrated with multiple protection functions, to meet international safety standards.