OB2269C.pdf 데이터시트 (총 13 페이지) - 파일 다운로드 OB2269C 데이타시트 다운로드

No Preview Available !

OB2269C
GENERAL DESCRIPTION
OB2269C is a highly integrated current mode PWM
control IC optimized for high performance, low
standby power and cost effective offline flyback
converter applications.
PWM switching frequency at normal operation is
externally programmable and trimmed to tight range.
At no load or light load condition, the IC operates in
extended ‘burst mode’ to minimize switching loss.
Lower standby power and higher conversion
efficiency is thus achieved.
VDD low startup current and low operating current
contribute to a reliable power on startup design with
OB2269C. A large value resistor could thus be used
in the startup circuit to minimize the standby power.
The internal slope compensation improves system
large signal stability and reduces the possible sub-
harmonic oscillation at high PWM duty cycle output.
Leading-edge blanking on current sense input
removes the signal glitch due to snubber circuit diode
reverse recovery. This greatly helps to reduce the
external component count and system cost in
application.
OB2269C offers complete protection coverage with
automatic self-recovery feature including Cycle-by-
Cycle current limiting (OCP), over load protection
(OLP), over temperature protection (OTP), VDD
over voltage protection (OVP) and under voltage
lockout (UVLO). The Gate-drive output is clamped
at 18V to protect the power MOSFET.
In OB2269C, OCP threshold slope is internally
optimized to reach constant output power limit over
universal AC input range.
Excellent EMI performance is achieved with On-
Bright proprietary frequency shuffling technique
together with soft switching control at the totem pole
gate drive output.
TYPICAL APPLICATION
Frequency Shuffling
The tone energy at below 20KHZ is minimized in
operation. Consequently, audio noise performance is
greatly improved.
OB2269C is offered in both SOP-8 and DIP-8
packages.
FEATURES
On-Bright Proprietary Frequency Shuffling
Technology for Improved EMI Performance
Extended Burst Mode Control For Improved
Efficiency and Minimum Standby Power Design
Audio Noise Free Operation
External Programmable PWM Switching
Frequency
Internal Synchronized Slope Compensation
Low VIN/VDD Startup Current(6.5uA) and Low
Operating Current (2.3mA)
Leading Edge Blanking on Current Sense Input
Complete Protection Coverage With Auto Self-
Recovery
o External Programmable Over Temperature
Protection (OTP)
o With or Without On-chip VDD OVP for
System OVP
o Under Voltage Lockout with Hysteresis
(UVLO)
o Gate Output Maximum Voltage Clamp (18V)
o Line Compensated Cycle-by-Cycle Over-
current Threshold Setting For Constant Output
Current Limiting Over Universal Input Voltage
Range (OCP)
o Over Load Protection. (OLP)
APPLICATIONS
Offline AC/DC flyback converter for
PC/TV/Set-Top Box Power Supplies
Open-frame SMPS
Battery Charger
©On-Bright Electronics
-1-
Confidential
OB_DOC_DS_69CC1

No Preview Available !

OB2269C
GENERAL INFORMATION
Pin Configuration
The OB2269C is offered in DIP and SOP packages
shown as below.
Ordering Information
Part Number
OB2269CAP
Description
With Frequency Shuffling,
DIP8, Pb-free
OB2269CAPV With Frequency Shuffling,
DIP8, Pb-free, no OVP
OB2269CCP
With Frequency Shuffling,
SOP8, Pb-free
OB2269CCPV With Frequency Shuffling,
SOP8, Pb-free, no OVP
Current Mode PWM ControllerFrequency Shuffling
Package Dissipation Rating
Package
DIP8
SOP8
RθJA (°C/W)
90
150
Absolute Maximum Ratings
Parameter
VDD/VIN DC Supply
Value
30 V
Voltage
VDD Zener Clamp
VoltageNote
VDD_Clamp+0.1V
VDD Clamp Continuous
10 mA
Current
VFB Input Voltage
VSENSE Input Voltage to Sense
Pin
-0.3 to 7V
-0.3 to 7V
VRT Input Voltage to RT Pin
VRI Input Voltage to RI Pin
Min/Max Operating Junction
-0.3 to 7V
-0.3 to 7V
-20 to 150 oC
Temperature TJ
Min/Max Storage
-55 to 150 oC
Temperature Tstg
Lead Temperature (Soldering, 260 oC
10secs)
Note: VDD_Clamp has a nominal value of 35V.
Stresses beyond those listed under “absolute maximum ratings”
may cause permanent damage to the device. These are stress
ratings only, functional operation of the device at these or any
other conditions beyond those indicated under “recommended
operating conditions” is not implied. Exposure to absolute
maximum-rated conditions for extended periods may affect device
reliability.
©On-Bright Electronics
-2-
Confidential
OB_DOC_DS_69CC1

No Preview Available !

Marking Information
OB2269C
Current Mode PWM ControllerFrequency Shuffling
TERMINAL ASSIGNMENTS
Pin Num Pin Name
1 GND
2 FB
3 VIN
4 RI
5 RT
6 SENSE
7 VDD
8 GATE
I/O Description
P Ground
I Feedback input pin. PWM duty cycle is determined by voltage level into this
pin and current-sense signal level at Pin 6.
I Connected through a large value resistor to rectified line input for Startup IC
supply and line voltage sensing.
I Internal Oscillator frequency setting pin. A resistor connected between RI
and GND sets the PWM frequency.
I Temperature sensing input pin. Connected through a NTC resistor to GND.
I Current sense input pin. Connected to MOSFET current sensing resistor
node.
P DC power supply pin.
O Totem-pole gate drive output for power MOSFET.
©On-Bright Electronics
-3-
Confidential
OB_DOC_DS_69CC1