The MOSFET is source-grounded, thus it is possible
to build flyback, boost and forward converters.
The device can work with secondary feedback and a
2.5V±2% internal reference, in addition to a high gain
error amplifier, makes possible also the use in appli-
cations either with primary feedback or not isolated.
The internal fixed oscillator frequency and the integrated
non dissipative start-up generator minimize the external
component count and power consumption.
The device is equipped with a standby function that
automatically reduces the oscillator frequency from
65 to 22 kHz under light load conditions to enhance
efficiency (Pin < 1W @ Pout = 0.5W with wide range
Internal protections like cycle-by-cycle current limiting,
latched output overvoltage protection, mains undervolt-
age protection (SMD version only) and thermal shut-
down generate a 'robust' design solution.
The IC uses a special leadframe with the ground pins
(6, 7 and 8 in minidip, 9 to16 in SO16W package) in-
ternally connected in order for heat to be easily re-
moved from the silicon die. An heatsink can then be
realized by simply making provision of few cm2 of
copper on the PCB. Furthermore, the pin(s) close to
the high-voltage one are not connected to ease com-
pliance with safety distances on the PCB.
[9, ..., 16]
[x] : L6590D (SO16W)
PIN CONNECTIONS (Top view)