m51996ap Renesas Electronics Corporation., m51996ap Datasheet - Page 13

• Manufacturer Part Number: m51996ap
• Description: Switching Regulator Control
• Manufacturer: Renesas Electronics Corporation.

M51996AP/AFP
Function Description
Type M51996AP and M51996AFP are especially designed for off-line primary PWM control IC of switching mode
power supply 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 replaced with
no problem.
Start-up Circuit Section
The start-up current is such low current level as typical 100 A, as shown in figure 1, when the V
from low level to start-up voltage 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
and I
start-up easy, because it takes rather long duration from V
REJ03D0836-0201 Rev.2.01 Nov 14, 2007
Page 13 of 35
CC
current is used to keep output low level. The large voltage difference between V
Figure 1 Circuit Current vs. Supply Voltage
CC(START)
≈ 100 µA
≈ 11 mA
I
I
CCO
.
CCL
Supply Voltage V
CC(START)
(STOP)
≈ 9.9 V
V
CC
to V
(START)
≈ 16.2 V
V
CC(STOP).
CC
CC
(V)
CC(START)
CC
and V
voltage is increased
CC(STOP)
makes