UCC28910D Datasheet, PDF (1/26 Pages) Texas Instruments – Low Stand-By Power, CV / CC PWM HV Switcher with Primary-Side

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UCC28910
PRELIMINARY INFORMATION
SLUS769 – July 2013
Low Stand-By Power, CV / CC PWM HV Switcher with Primary-Side
Regulation
FEATURES
 Primary Side Regulation (PSR)
 +/- 5% Voltage Regulation
 +/- 5% Current Regulation
 Automatic line variation compensation
 Automatic primary inductance tolerance compensation
 <30mW Stand-by Power
 Valley Switching
 Thermal Shut down
 Over Voltage, and Low Line protection
 Frequency Jitter
 Integrated high voltage current source for low standby
consumption
APPLICATIONS
 USB compliant adapters for Cell Phones, Tablets,
Cameras
 5-7 Watt AC/DC Power Supplies
Simplified Application Diagram
and Typical V-I Regulation
UCC28910
GND
DRAIN
GND
GND
IPK
VDD
VS
DESCRIPTION
The UCC28910 is dedicated to flyback power supplies
and provides isolated output voltage and current
regulation without the use of an optical coupler. The
device incorporates a 700 V power FET and a controller
that processes operating information from the auxiliary
flyback winding and from the power FET to provide
precise output voltage and current control.
The integrated high voltage current source and the
controller current consumption are dynamically adjusted
to allow very low stand-by power.
Control algorithms in the UCC28910 allow operating
efficiencies to meet or exceed applicable standards.
Discontinuous conduction mode (DCM) with valley
switching is used to reduce switching losses. A
combination of switching frequency and peak primary
current amplitude modulation is used to keep conversion
efficiency high across the full load and input voltage
range.
This controller has a maximum switching frequency of
115 kHz and the protection features help to keep
secondary and primary component stress levels in check
across the operating range.
The controlled slope of the DRAIN voltage, during
internal FET switch on and switch off, and the frequency
jitter help to reduce EMI filter cost
Typical target output V-I Characteristic
5
±5%
4
±5%
3
2
1
USB Specs. 1.1
Typical Application
0.25
0.5
0.75
1
1.25
1.5
Output Current (A)
1