OB2263
Current Mode PWM Controller
Frequency Shuffling
GENERAL DESCRIPTION
OB2263 is a highly integrated current mode PWM
control IC optimized for high performance, low
standby power and cost effective offline flyback
converter applications in sub 30W range.
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
OB2263. 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(CS) input
removes the signal glitch due to snubber circuit diode
reverse recovery and thus greatly reduces the external
component count and system cost in the design.
OB2263 offers complete protection coverage with
automatic self-recovery feature including Cycle-by-
Cycle current limiting (OCP), over load protection
(OLP), VDD over voltage clamp and under voltage
lockout (UVLO). The Gate-drive output is clamped
to maximum 18V to protect the power MOSFET.
Excellent EMI performance is achieved with On-
Bright proprietary frequency shuffling technique
together with soft switching control at the totem pole
gate drive output.
Tone energy at below 20KHZ is minimized in the
design and audio noise is eliminated during operation.
OB2263 is offered in SOT23-6, 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 VDD Startup Current and Low Operating
Current (1.4mA)
■
Leading Edge Blanking on Current Sense Input
■
Good Protection Coverage With Auto Self-
Recovery
o
VDD Over Voltage Clamp and Under Voltage
Lockout with Hysteresis (UVLO)
o
Gate Output Maximum Voltage Clamp (18V)
o
On-Bright Proprietary Line Input Compensated
Cycle-by-Cycle Over-current Threshold Setting
For Constant Output Power Limiting Over
Universal Input Voltage Range.
o
Overload Protection (OLP)
■
to
TYPICAL APPLICATION
On
-
Br
ig
ht
©On-Bright Electronics
Confidential
-1-
OB_DOC_DS_63B2
re
le
a
se
d
Ch
ar
m
APPLICATIONS
Offline AC/DC flyback converter for
■
Battery Charger
■
Power Adaptor
■
Set-Top Box Power Supplies
■
Open-frame SMPS
ri
ch
(创
裕
企
业
)
OB2263
Current Mode PWM Controller
Frequency Shuffling
GENERAL INFORMATION
Pin Configuration
The OB2263 is offered in SOT23-6, DIP8 and SOP8
packages, shown as below.
Part Number
OB2263MP
OB2263AP
OB2263CP
Description
SOT23-6, Pb-free
DIP8, Pb-free
SOP8, Pb-free
200
Absolute Maximum Ratings
Parameter
Value
VDD DC Supply Voltage
30 V
VDD Clamp Voltage
34V
VDD DC Clamp Current
10 mA
V
FB
Input Voltage
-0.3 to 7V
V
SENSE
Input Voltage to Sense
-0.3 to 7V
Pin
V
RI
Input Voltage to RI Pin
-0.3 to 7V
Min/Max Operating Junction
-20 to 150
o
C
Temperature T
J
Min/Max Storage Temperature -55 to 160
o
C
T
stg
Note:
Stresses beyond those listed under “absolute maximum
Ordering Information
On
-
Br
ig
ht
©On-Bright Electronics
Confidential
-2-
OB_DOC_DS_63B2
re
le
a
se
d
to
Ch
ar
m
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.
ri
ch
(创
裕
企
DIP8
SOP8
SOT23-6
90
150
业
(°C/W)
)
Package Dissipation Rating
RθJA
Package
OB2263
Current Mode PWM Controller
Frequency Shuffling
Marking Information
Pin Name
GND
FB
RI
SENSE
VDD
GATE
I/O
P
I
I
I
P
O
RECOMMENDED OPERATING CONDITION
Symbol
VDD
RI
T
A
Parameter
Min
Max
10 to 30
100
-20 to 85
Unit
V
Kohm
o
C
On
-
Br
ig
ht
©On-Bright Electronics
Confidential
-3-
OB_DOC_DS_63B2
re
le
a
VDD Supply Voltage
RI Resistor Value
Operating Ambient Temperature
se
d
Description
Ground
Feedback input pin. The PWM duty cycle is determined by voltage level into this pin and
SENSE pin input.
Internal Oscillator frequency setting pin. A resistor connected between RI and GND sets
the PWM frequency.
Current sense input pin. Connected to MOSFET current sensing resistor node.
Chip DC power supply pin.
Totem-pole gate drive output for the power MOSFET.
to
Ch
ar
m
TERMINAL ASSIGNMENTS
ri
ch
(创
裕
企
业
)
OB2263
Current Mode PWM Controller
Frequency Shuffling
BLOCK DIAGRAM
On
-
Br
ig
ht
©On-Bright Electronics
Confidential
-4-
OB_DOC_DS_63B2
re
le
a
se
d
to
Ch
ar
m
ri
ch
(创
裕
企
业
)
OB2263
Current Mode PWM Controller
Frequency Shuffling
ESD INFORMATION
Symbol
HBM
MM
Parameter
Human Body Model
Machine Model
Test Conditions
MIL-STD
JEDEC-STD
Min
Typ
3
150
Max
Unit
KV
V
ELECTRICAL CHARACTERISTICS
(T
A
= 25
O
C if not otherwise noted)
Symbol
Parameter
Supply Voltage (VDD)
I_VDD_Startup
VDD Start up
Current
I_VDD_Ops
UVLO(ON)
Operation Current
Test Conditions
VDD =12.5V, RI=100K
Measure Leakage current
into VDD
VDD=16V,
RI=100Kohm, V
FB
=3V
7.8
13
Min
Typ
3
1.4
Max
20
裕
9.8
15
0.75
0.80
70
(创
ch
8.8
14
34
2.0
4.8
0.8
3.7
35
6
75
300
40
75
0.70
0.75
60
65
VDD Under Voltage
Lockout Enter
UVLO(OFF)
VDD Under Voltage
Lockout Exit
(Recovery)
VDD_Clamp
VDD Zener Clamp
Voltage
Feedback Input Section(FB Pin)
A
VCS
PWM Input Gain
V
FB_
Open
V
FB
Open Loop
Voltage
I
FB
_Short
FB pin short circuit
current
V
TH
_0D
Zero Duty Cycle FB
Threshold Voltage
V
TH
_PL
Power Limiting FB
Threshold Voltage
T
D
_PL
Power limiting
Debounce Time
Z
FB
_IN
Input Impedance
DC_MAX
Maximum Duty
Cycle
I
VDD
= 10 mA
ΔV
FB
/ΔV
cs
Ch
ar
m
ri
to
se
d
Short FB pin to GND and
measure current
VDD = 16V,
RI=100Kohm
re
le
a
Br
ig
ht
VDD=18V,
RI=100Kohm, FB=3V,
CS=0
RI = 100 Kohm
VDD = 16V,
CS>V
TH
_OC, FB=3.3V
FB=3.3V, RI=100 Kohm
Current Sense Input(Sense Pin)
T_blanking
Leading edge
blanking time
Z
SENSE
_IN
Input Impedance
T
D
_OC
Over Current
Detection and
Control Delay
V
TH
_OC
Over Current
Threshold Voltage at
zero Duty Cycle
Oscillator
F
OSC
Normal Oscillation
Frequency
On
-
RI = 100 Kohm
©On-Bright Electronics
Confidential
-5-
OB_DOC_DS_63B2
企
uA
mA
V
V
V
V/V
V
mA
V
V
ns
V
Unit
mSec
Kohm
%
Kohm
nSec
KHZ
业
)
电子工程世界
