MP4032-1—PRIMARY-SIDE-CONTROLLED, OFFLINE LED DRIVER WITH FULLY-INTEGRATED MOSFET
MP4032-1 Rev. 1.02 www.MonolithicPower.com 9
7/15/2013 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2013 MPS. All Rights Reserved.
PIN FUNCTIONS
Pin # Name Pin Function
1 COMP
Loop Compensation. Connects a compensation network to stabilize the LED driver and
get an accurate LED driver current.
2 MULT
Multiplier Input. Connect this pin to the tap of resistor divider from the rectified voltage of
the AC line. The half-wave sinusoid signal on this pin provides a reference signal for the
internal current control loop.
3 ZCD
Zero Current Detection Input. A negative going-edge triggers the turn-on signal of the
internal MOSFET. Connect this pin to a resistor divider between the auxiliary winding to
GND. Over-voltage condition is detected through ZCD. For each switching turn-off interval,
if the ZCD voltage exceeds the over-voltage-protection (OVP) threshold after the 1.9μs
blanking time, OVP will trigger and the system will stop switching until auto-restart.
4 VCC
Power Supply Input. Powers both the control signal and the internal high-voltage MOSFET
gate driver. Bypass to ground with an external bulk capacitor (typically 22μF) to reduce
ripple.
5 GND Ground. Current return for the control signal and the gate drive signal.
6 CS
Internal MOSFET Source and Current Sense Input. Connect a current-sensing resistor
from this pin to GND to set the LED current. Senses the MOSFET current. Comparing the
resulting voltage and the internal sinusoidal-current reference signal determines when the
MOSFET turns off. If the pin voltage exceeds the current limit threshold of 2.27V (after turn-
on blanking) the gate drive will turn off.
7 NC
8 DRAIN
Drain of the Internal MOSFET. Provides charging current from the rectified AC line voltage
to VCC for start-up.
