NCP1126_12 Datasheet, PDF (1/13 Pages) ON Semiconductor – High Voltage Switcher for Offline Power Supplies

NCP1126, NCP1129
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High Voltage Switcher for
Offline Power Supplies
The NCP1126/NCP1129 switcher offers everything needed to build
reliable and compact AC−DC switching power supplies with minimal
surrounding elements. Incorporating a rugged 650 V MOSFET,
converters built with the NCP112X can be safely designed for
international conditions without jeopardizing the overall reliability.
The NCP112X implements peak current mode control with adjustable
ramp compensation that ensures stability in Continuous Conduction
Mode (CCM) operation. With an external resistor, the maximum peak
current is adjustable, allowing the designer the ability to inject ramp
compensation to stabilize CCM power supplies.
A short circuit fault condition is independently detected from the
auxiliary winding voltage resulting in improved short circuit
protection with true overload detection. The Source pin provides
access to the MOSFET source, allowing for overpower compensation.
With a supply range up to 26 V, the switcher also provides a jittered
65 kHz or 100 kHz switching frequency operated in peak current
mode control. When the power on the secondary side starts to
decrease, the switcher automatically folds back its switching
frequency down to a minimum level of 26 kHz. As the power further
goes down, the part enters skip cycle while limiting the peak current.
Features
• 650 V Avalanche Rated MOSFET (2 W NCP1129 / 6 W NCP1126)
• Fixed−Frequency 65 or 100 kHz Current−Mode Control Operation
• Frequency Foldback Down to 26 kHz and Skip−Cycle in Light Load
Conditions
• Adjustable Current Limit
• Internal Ramp Compensation
• Internal Fixed 4 ms Soft−Start
• 200 ms Timer−Based Auto−Recovery Short−Circuit Protection
• Frequency Jittering in Normal and Frequency Foldback Modes
• Option for Auto−Recovery or Latched Short−Circuit Protection
• Up to 26 V V_CC Operation
• Less than 100 mW Standby Power at High Line
• EPS 2.0 Compliant
• 7−Pin Package Provides Creepage Distance
• These are Pb−Free Devices
Typical Applications
• Power Supplies for DVDs, CD Players, Set Top Boxes, TVs
• Auxiliary Power Supplies (USB, Appliances, TVs)
This document contains information on a product under development. ON Semiconductor
reserves the right to change or discontinue this product without notice.
http://onsemi.com
PDIP−7
P SUFFIX
CASE 626B
MARKING DIAGRAM
112xyPzzz
AWL
YYWWG
1
x
= Specific Device Code
6 = NCP1126
9 = NCP1129
y
= A or B
A = Latch
B = Auto−recovery
zzz = Frequency
65 = 65 kHz
100 = 100 kHz
A
= Assembly Location
WL = Wafer Lot
YY
= Year
WW = Work Week
G
= Pb−Free Package
PIN CONNECTIONS
1
VCC
2
FB
3
CS
4
Source
8
GND
6 Drain
5
Drain
(Top View)
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 4 of this data sheet.
© Semiconductor Components Industries, LLC, 2012
1
October, 2012 − Rev. P0
Publication Order Number:
NCP1126/D