LinearVoltageRegulators Motorola Semiconductor Products, LinearVoltageRegulators Datasheet - Page 29

• Manufacturer Part Number: LinearVoltageRegulators
• Description: Analog And Interface Integratedcircuits Selector Guide & Cross Reference
• Manufacturer: Motorola Semiconductor Products

270 Vac
Power Factor Controllers
MC33368D, P
T J = –25 to +125 C, Case 751K, 648
functions as a boost preconverter in off–line power supply
applications. MC33368 is optimized for low power, high
density power supplies requiring minimum board area,
reduced component count, and low power dissipation. The
narrow body SOIC package provides a small footprint.
Integration of the high voltage startup saves approximately
0.7 W of power compared to resistor bootstrapped circuits.
switching, a one quadrant multiplier to force the line current to
follow the instantaneous line voltage, a zero current detector
to ensure critical conduction operation, a transconductance
error amplifier, a current sensing comparator, a 5.0 V
MOTOROLA
58
92 to
The MC33368 is an active power factor controller that
The MC33368 features a watchdog timer to initiate output
R3
10.5 k
R5
1.3 M
330 F
1.0 M
Filter
EMI
C9
R8
V ref
C2
0.01
AGnd
Mult
D2
D1
RD
8
2
5
1.5 V
Multiplier
V ref
1N5406
D3
D4
Load Detect
4
Low
Comp
C1
1.0
(continued)
Quickstart
C5
1.0
Q
1.08 x V ref
Overvoltage
Comparator
Set Dominant
MC33368
R S Latch
R
R
S
S
S
Timer
1
Q
V ref
C6
0.1
R
Reference
5.0 V
V ref
Leading Edge
Zero
Current
Detect
Blanking
UVLO
15 V
Frequency
Clamp
reference, an undervoltage lockout (UVLO) circuit which
monitors the V CC supply voltage, and a CMOS driver for
driving
programmable output switching frequency clamp. Protection
features include an output overvoltage comparator to
minimize overshoot, a restart delay timer, and cycle–by–
cycle current limiting.
1.2/1.0
Lossless Off–Line Startup
Output Overvoltage Comparator
Leading Edge Blanking (LEB) for Noise Immunity
Watchdog Timer to Initiate Switching
Restart Delay Timer
16
ANALOG AND INTERFACE INTEGRATED CIRCUITS
3
13/8.0
Line
FB
1.5 V
MOSFETs.
SELECTOR GUIDE & CROSS REFERENCE
V CC
ZCD
Gate
PGnd
10
13
FC
LEB
CS
12
11
9
6
7
1N4744
15 V
D8
The
22 k
R4
C8
0.001
V ref
C4
100
MC33368
R13
R10
10 k
51
C7
470 pF
R11
10
R9
10
D6
1N4934
Q1
T
also
MTW20N50E
MUR460
R7
0.1
D5
820 k
includes
10 k
R2
R1
C3
330
400 V
a