Product Overview

Product Overview
NCP1247: PWM Controller, Fixed Frequency, Flyback Converters, USB-Pd
Reference Design
For complete documentation, see the data sheet
Product Description
The NCP1247 is a new fixed-frequency current-mode PWM controller featuring Dynamic Self-Supply. This function greatly simplifies
the design of the auxiliary supply and the Vcc capacitor by activating the internal startup current source to supply the controller
during start-up, transients, latch, stand-by etc. This device contains a special HV detector which detects the application unplug from
the AC input line and triggers the X2 discharge current. The HV structure also includes brown-out detection circuitry.
The NCP1247 features a timer-based fault detection that ensures the detection of overload and an adjustable power compensation
to help keep the maximum power independent of the input voltage.
Due to frequency foldback, the controller exhibits excellent efficiency in light load condition while still achieving very low standby
power consumption. Internal frequency jittering, ramp compensation, and a versatile latch input make this controller an excellent
candidate for robust power supply designs.
A dedicated off mode allows the SMPS to reach extremely low no load input power consumption when combined with secondary
side controller NCP4353 or NCP4354. When used together, the SMPS is capable of achieving <10 mW no load input power
consumption. The secondary side controller signals the NCP1247 to enter a sleep mode, minimizing the power consumption of the
control circuitry. The NCP1247 is very similar in its functionality to the NCP1246. The NCP1247 is designed to get better
performance out of systems with synchronous rectification.
NCP1247
- Adds C & D option for different Brown Out threshold
- Enhanced operation with Sync Rec in light load
- Increased HV timer
- Revised X2 discharge sequence
This product is IEC60950 compliant. Please see the test report and certification in the Conformance report section below.
Features
• Frequency foldback and skip mode
• Timer-based overload protection with latched (A version) or
auto-recovery (B version) operation
• High-voltage startup with dynamic self supply
• Integrated brown-out detection
• Frequency Modulation
• Adjustable overpower protection
• Latch off input
Applications
•
•
•
•
AC-DC Adapters
LCD TV power supplies
USB-Pd (USB Power Delivery)
Offline USB Pd
Benefits
• Optimized efficiency across the entire load range
• Protection against overcurrent and short circuit
•
•
•
•
Simplifies the design of the auxiliary supply
Protects against any drops in line voltage
Softened EMI signature
Automatically adjusts the current limit depending on the line
input voltage (high line or low line)
• Protection against faults
End Products
• Notebook Computers
• Offline USB Power Delivery SMPS
Part Electrical Specifications
Product
Compliance
Status
Topolog
y
Control
Mode
fsw Typ
(kHz)
StandUVLO
by Mode (V)
Short
Circuit
Protecti
on
Latch
Soft
Start
VCC Max Drive
(V)
Cap.
(mA)
Packag
e Type
NCP1247AD065R2G
Pb-free
Active
Flyback
Current
Mode
65
Yes
8.9
Yes
Yes
Yes
28
500 /
800
SOIC-7
Active
Flyback
Current
Mode
100
Yes
8.9
Yes
Yes
Yes
28
500 /
800
SOIC-7
Active
Flyback
Current
Mode
65
Yes
8.9
Yes
Yes
Yes
28
500 /
800
SOIC-7
Active
Flyback
Current
Mode
100
Yes
8.9
Yes
Yes
Yes
28
500 /
800
SOIC-7
Active
Flyback
Current
Mode
65
Yes
8.9
Yes
Yes
Yes
28
500 /
800
SOIC-7
Active
Flyback
Current
Mode
100
Yes
8.9
Yes
Yes
Yes
28
500 /
800
SOIC-7
Active
Flyback
Current
Mode
65
Yes
8.9
Yes
Yes
Yes
28
500 /
800
SOIC-7
Active
Flyback
Current
Mode
100
Yes
8.9
Yes
Yes
Yes
28
500 /
800
SOIC-7
Halide free
NCP1247AD100R2G
Pb-free
Halide free
NCP1247BD065R2G
Pb-free
Halide free
NCP1247BD100R2G
Pb-free
Halide free
NCP1247CD065R2G
Pb-free
Halide free
NCP1247CD100R2G
Pb-free
Halide free
NCP1247DD065R2G
Pb-free
Halide free
NCP1247DD100R2G
Pb-free
Halide free
For more information please contact your local sales support at www.onsemi.com
Created on: 6/30/2016