The Typical Application Circuit of iW1689

The  iW1689  is not only efficiency, but also provide some key built-in protection features can reduce the number of external components to reduce B0M cost. It eliminates the need for loop compensation components, and provide a stable output state of the entire work. In addition, the built-in power limit function allows to optimize the design of the transformer in the common off-line applications, and support a wide input voltage range. Under light load, the iW1689 has a very low start-up power and operating current, which makes it possible to meet the requirements of the new power standard for the average efficiency and standby power consumption.

The iW1689 built-in constant current mode and constant voltage mode, using the iWatt primary patented feedback algorithm to control the secondary output, without any sub-detection and control circuit, iW1689 accurate secondary constant current. Its high power output, the PWM mode to PFM mode control, in the low power output, to minimize power consumption.
The iW1689 the main features include: As a result of the primary feedback, no opto-isolated feedback circuit simplifies the design, support the work of the multi-mode in order to achieve maximum efficiency, ± 4% output voltage regulation, requires no external compensation components, built-in soft-start function. Short circuit protection, the secondary constant current control function, with a primary feedback to the fixed 40kHz switching frequency.