Sample &
Buy
Support &
Community
Product
Folder
Tools &
Software
Technical
Documents
UCC28730
SLUSBL5 –FEBRUARY 2015
UCC28730 Zero-Power Standby PSR Flyback Controller
with CVCC and Wake-Up Monitoring
1 Features
3 Description
The UCC28730 isolated-flyback power supply
controller provides Constant-Voltage (CV) and
Constant-Current (CC) output regulation without the
use of an optical coupler, and wake-up signal
detection to improve transient response to large load
steps. A minimum switching frequency of 30 Hz
facilitates achieving less than 5 mW of no-load
power. This device processes information from the
primary power switch and an auxiliary flyback winding
for precise control of output voltage and current. The
wake-up monitoring works with a secondary-side
alarm device such as the UCC24650 to deliver rapid
response to heavy load steps using minimal output
capacitance.
1
•
•
•
•
Enables Zero-Power (<5 mW) Standby
Consumption
Smart Wake-Up Detection Enables Smallest
Output Capacitance
Primary-Side Regulation (PSR) Eliminates Opto-
coupler
±5% Voltage Regulation and Current Regulation
Across Line and Load
•
•
700-V Start-up Switch
83-kHz Maximum Switching Frequency Enables
Low Stand-by Power Charger Designs
•
Resonant-Ring Valley-Switching Operation for
Highest Overall Efficiency
An internal 700-V start-up switch, dynamically-
controlled operating states and a tailored modulation
profile support ultra-low stand-by power without
sacrificing start-up time or output transient response.
Control algorithms in the UCC28730 allow operating
efficiencies to meet or exceed applicable standards.
Discontinuous conduction mode (DCM) operation
with valley-switching reduces switching losses.
Modulation of the switching frequency and primary
current peak amplitude (FM and AM) keeps the
conversion efficiency high across the entire load and
line ranges.
•
•
•
Frequency-Dither to Ease EMI Compliance
Clamped Gate-Drive Output for MOSFET
Over-Voltage, Low-Line, and Over-Current
Protection Functions
•
•
Programmable Cable Compensation
SOIC-7 Package
2 Applications
•
Adapters and Chargers for Smart Phones,
Tablets, and Other Consumer Electronics
Device Information(1)
•
•
TV and Monitor Power Supplies
PART NUMBER
PACKAGE
BODY SIZE (NOM)
SMPS for Home Appliances and Industrial
Automation
UCC28730
SOIC (7)
4.90 mm x 3.90 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
•
Standby and Auxiliary Power Supplies
Simplified Schematic
Zero-Power Input Consumption at No-Load
VBULK
VOUT
IOUT
NP
NS
VSEC
CB1
CB2
UCC24650
COUT
5
3
WAKE VDD
1
2
VAC
ENS
GND
RPL
DS
5.1 V +/-5% Cout = 540 mF
UCC28730
DA
VAUX
NA
1
VDD
HV
7
CVDD
M1
RS1
Input
Voltage
No-load
Input Power
DRV
CS
6
5
RLC
2
3
VS
115 VRMS
230 VRMS
3.0 mW
3.5 mW
CBC
GND
4
RS2
RCBC
RCS
2-A Load Step
Switching Pulses
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.