NCP1562A Datasheet, PDF (1/26 Pages) ON Semiconductor – High Performance Active Clamp/Reset PWM Controller

NCP1562A, NCP1562B
High Performance Active
Clamp/Reset PWM Controller
The NCP1562x is a family of voltage mode controllers designed
for dc- dc converters requiring high- efficiency and low parts count.
These controllers incorporate two in phase outputs with an overlap
delay to prevent simultaneous conduction and facilitates soft
switching. The main output is designed for driving a forward
converter primary MOSFET. The secondary output is designed for
driving an active clamp circuit MOSFET, a synchronous rectifier on
the secondary side, or an asymmetric half bridge circuit.
The NCP1562 family reduces component count and system size by
incorporating high accuracy on critical specifications such as
maximum duty cycle limit, undervoltage detector and overcurrent
threshold. Two distinctive features of the NCP1562 are soft- stop and
a cycle skip current limit with a time threshold. Soft- stop circuitry
powers down the converter in a controlled manner if a severe fault is
detected. The cycle skip detector enables a soft- stop sequence if a
continuous overcurrent condition is present.
Additional features found in the NCP1562 include line feed-
forward, frequency synchronization up to 1.0 MHz, cycle- by- cycle
current limit with leading edge blanking (LEB), independent under
and overvoltage detectors, adjustable output overlap delay,
programmable maximum duty cycle, internal startup circuit and
soft- start.
Features
 Dual Control Outputs with Adjustable Overlap Delay
 >2.0 A Output Drive Capability
 Soft- Stop Powers Down Converter in a Controlled Manner
 Cycle- by- Cycle Current Limit
 Cycle Skip Initiated if Continuous Current Limit Condition Exists
 Voltage Mode Operation with Input Voltage Feedforward
 Fixed Frequency Operation up to 1.0 MHz
 Bidirectional Frequency Synchronization
 Independent Line Undervoltage and Overvoltage Detectors
 Accurate Programmable Maximum Duty Cycle Limit
 Programmable Maximum Volt- Second Product
 Programmable Soft- Start
 Internal 100 V Startup Circuit
 Precision 5.0 V Reference
 These are Pb- Free Devices
Typical Applications
 Telecommunications Power Converters
 Low Output Voltage Converters using Control Driven Synchronous
Rectifier
 Industrial Power Converters
 42 V Automotive System
 ATX Power Supplies
http://onsemi.com
MARKING
DIAGRAMS
TSSOP- 16
NCP
16
DT SUFFIX
562x
CASE 948F
ALYWG
1
G
SO- 16
D SUFFIX
CASE 751B
NCP1562xG
AWLYWW
x
= Current Limit (A, B)
A
= Assembly Location
WL, L = Wafer Lot
Y
= Year
WW, W = Work Week
G or G = Pb--Free Package
(Note: Microdot may be in either location)
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 24 of this data sheet.
 Semiconductor Components Industries, LLC, 2010
1
November, 2010 - Rev. 5
Publication Order Number:
NCP1562A/D