M51995AP/AFP

REJ03D0835-0300 Rev.3.00 Jun 06, 2008

Page 16 of 40

Function Description

Type M51995AP and M51995AFP are especially designed for off-line primary PWM control IC of switching mode

power supply (SMPS) to get DC voltage from AC power supply.

Using this IC, smart SMPS can be realized with reasonable cost and compact size as the number of external electric

parts can be reduced and also parts can be replaced by reasonable one.

In the following circuit diagram, MOS FET is used for output transistor, however bipolar transistor can be used with no

problem.

Start-up Circuit Section

The start-up current is such low current level as typical 90

µA, as shown in figure 1, when the V

In this voltage range, only a few parts in this IC, which has the function to make the output voltage low level, is alive

≈ 14 mA

≈ 90 µA

(STOP)

≈ 9.9 V

(START)

≈ 16.2 V

Figure 1 Circuit Current vs. Supply Voltage