The STR-A6251/51M/52 Series from Allegro MicroSystems Europe is a family of low-output power offline switching regulator ICs featuring a novel 'jittering' function that minimises the need for external EMI noise-filtering circuitry.
The devices use a PWM (pulse-width modulation) topology to provide an output power of up to 20 W with a universal input or 24 W with a 230 V a.c. input. Each device incorporates a variety of functions to realise a simple and reliable design in a switched-mode power supply system, including primary controlled constant-voltage/constant-current operation, automatic standby, soft start, circuit protection and an avalanche-energy-guaranteed MOSFET.
The frequency jittering function enables cost reduction in the EMI noise-filtering circuitry by suppressing EMI noise. The centre frequency of the PWM operation is set to 50 kHz for the STR-A6251/52 and 67 kHz for the STR-A6251M. The frequency jittering provides a variation of ±2,5% of the centre frequency, and the fluctuation speed is adjusted by an external capacitor for optimum results.
A number of other features reduce the overall costs of designs based on these ICs. The primary constant output eliminates the need for secondary-side control circuitry, which would normally include an operational amplifier, current-sensing resistor and passive components.
In addition to the overload protection, each device includes pulse-by-pulse overcurrent protection, overvoltage protection with latch, and thermal shutdown with latch. Auto-burst standby reduces standby input power to less than 100 mV at zero load and 264 V a.c., while the soft-start reduces MOSFET stress during start-up.
The proprietary 900 V BCD process connected to the internal MOSFET's drain to power the control circuit simplifies the peripheral circuit design and improves the system's efficiency. The STR-A6251/51M/52 Series is targeted at battery-changer, standby and low- output power-supply applications in the consumer, communication, industrial and home appliance markets, and is supplied in an 8-pin dual-inline package.
For more information contact Simon Churches, Arrow Altech Distribution, +27 (0)11 923 9600, [email protected]
New compact AC-DC PSU series Vepac Electronics
Power Electronics / Power Management
COSEL has announced the expansion of its medical power offering with the addition of the new UMA series, the first three models being the 30 W UMA30F, the 60 W UMA60F and the 120 W UMA120F.
Read more...High reliability memories Altron Arrow
DSP, Micros & Memory
Infineon’s mil-temp memories offer a wide selection of volatile and non-volatile memories for applications that meet QML-Q certifications and offer support for mil-aero applications.
Read more...Reference board for cardio monitoring Altron Arrow
Telecoms, Datacoms, Wireless, IoT
The STDES-ESP01 reference board from STMicroelectronics demonstrates the capability of the ST1VAFE6AX and ST1VAFE3BX biosensors to detect ECG and SCG signals.
Read more...USB Type-C-powered controllers Future Electronics
Power Electronics / Power Management
Diodes Incorporated has released two USB Type-C PD 3.1 extended power range sink controllers that can be embedded into battery-powered devices.
Read more...ST MCUs extend ultra-low power innovation Altron Arrow
DSP, Micros & Memory
STMicroelectronics has introduced new STM32U3 microcontrollers with cutting-edge power-saving innovations that ease deployment of smart connected tech, especially in remote locations.
Read more...Multicell battery monitoring Altron Arrow
Power Electronics / Power Management
The LTC6811 from Analog Devices is a multicell battery stack monitor that measures up to 12 series connected battery cells with a total measurement error of less than 1,2 mV.
Read more...Innovative satellite navigation receiver Altron Arrow
Telecoms, Datacoms, Wireless, IoT
STMicroelectronics has released an innovative satellite navigation receiver to democratise precise positioning for automotive and industrial applications.
Read more...LED driver for industrial power supply indication Altron Arrow
Editor's Choice Circuit & System Protection
A simple and small solution for driving an LED to provide visual feedback in the presence/absence of a system’s power using a chip not originally designed for this purpose.
printer friendly version