OB2536.pdf 데이터시트 (총 10 페이지) - 파일 다운로드 OB2536 데이타시트 다운로드

No Preview Available !

OB2536
High Precision CC/CV Primary-Side PWM Controller
Product Specification
GENERAL DESCRIPTION
OB2536 is a high performance offline PWM Power
switch for low power AC/DC charger and adaptor
applications. It operates in primary-side sensing
and regulation. Consequently, opto-coupler and
TL431 could be eliminated. Proprietary Constant
Voltage (CV) and Constant Current (CC) control is
integrated as shown in the figure below.
In CC control, the current and output power setting
can be adjusted externally by the sense resistor
Rs at CS pin. In CV control, multi-mode operations
are utilized to achieve high performance and high
efficiency. In addition, good load regulation is
achieved by the built-in cable drop compensation.
Device operates in PFM in CC mode as well at
large load condition and it operates in PWM with
frequency reduction at light/medium load.
OB2536 offers power on soft start control and
protection coverage with auto-recovery features
including Cycle-by-Cycle current limiting, VDD
OVP, VDD clamp and UVLO. Excellent EMI
performance is achieved with On-Bright
proprietary frequency shuffling technique.
High precision constant voltage (CV) and constant
current (CC) can be achieved by OB2536.
.
FEATURES
„ 5% Constant Voltage Regulation, 5%
Constant Current Regulation at Universal AC
input
„ Primary-side Sensing and Regulation Without
TL431 and Opto-coupler
„ Programmable CV and CC Regulation
„ Adjustable Constant Current and Output
Power Setting
„ Built-in Secondary Constant Current Control
with Primary Side Feedback
„ Built-in Adaptive Current Peak Regulation
„ Built-in Primary winding inductance
compensation
„ Programmable Cable drop Compensation
„ Power on Soft-start
„ Built-in Leading Edge Blanking (LEB)
„ Cycle-by-Cycle Current Limiting
„ VDD Under Voltage Lockout with Hysteresis
(UVLO)
„ VDD OVP
„ VDD Clamp
APPLICATIONS
Low Power AC/DC offline SMPS for
„ Cell Phone Charger
„ Digital Cameras Charger
„ Small Power Adaptor
„ Auxiliary Power for PC, TV etc.
„ Linear Regulator/RCC Replacement
OB2536 is offered in DIP8 package.
Fig.1. Typical CC/CV Curve
TYPICAL APPLICATION
©On-Bright Electronics
Confidential
-1-
Preliminary Datasheet
OB_DOC_DS_253600

No Preview Available !

OB2536
High Precision CC/CV Primary-Side PWM Controller
GENERAL INFORMATION
Pin Configuration
The pin map is shown as below for DIP8.
VDD 1
8 GND
COMP
2
7 GND
INV 3
6 DRAIN
CS 4
5 DRAIN
Ordering Information
Part Number
Description
OB2536AP
DIP8, Pb-free, Tube
Package Dissipation Rating
Package
RθJA (/W)
DIP8
75
Note: Drain Pin Connected 100mm2 PCB copper clad.
.
Absolute Maximum Ratings
Parameter
Value
Drain Voltage (off state)
-0.3V to Bvdss
VDD Voltage
VDD Zener Clamp
Continuous Current
-0.3 to VDD_clamp
10 mA
COMP Voltage
-0.3 to 7V
CS Input Voltage
-0.3 to 7V
INV Input Voltage
-0.3 to 7V
Max Operating Junction
Temperature TJ
Min/Max Storage
Temperature Tstg
150 oC
-55 to 150 oC
Lead Temperature
(Soldering, 10secs)
260 oC
Note: 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
Confidential
-2-
Preliminary Datasheet
OB_DOC_DS_253600

No Preview Available !

Marking Information
OB2536
High Precision CC/CV Primary-Side PWM Controller
TERMINAL ASSIGNMENTS
Pin Num Pin Name
1 VDD
2 COMP
3 INV
4 CS
5/6 DRAIN
7/8 GND
I/O Description
P Power Supply
I Loop Compensation for CV Stability
The voltage feedback from auxiliary winding. Connected to resistor
I divider from auxiliary winding reflecting output voltage. PWM duty cycle
is determined by EA output and current sense signal at pin 4.
I Current sense input
O
HV MOSFET Drain Pin. The Drain pin is connected to the primary lead
of the transformer
P Ground
OUTPUT POWER TABLE
Product
OB2536
230VAC±15%
Adapter1
16W
85-264VAC
Adapter1
11W
Notes:
1. Maximum practical continuous power in an Adapter design with sufficient drain pattern as a heat sink, at 50ambient.
©On-Bright Electronics
Confidential
-3-
Preliminary Datasheet
OB_DOC_DS_253600

No Preview Available !

BLOCK DIAGRAM
OB2536
High Precision CC/CV Primary-Side PWM Controller
©On-Bright Electronics
Confidential
-4-
Preliminary Datasheet
OB_DOC_DS_253600

No Preview Available !

OB2536
High Precision CC/CV Primary-Side PWM Controller
ELECTRICAL CHARACTERISTICS
(TA = 25, VDD=VDDG=16V, if not otherwise noted)
Symbol
Parameter
Test Conditions
Min Typ Max Unit
Supply Voltage (VDD) Section
I DD ST
I DD op
Standby Current
Operation Current
VDD=13V
Operation supply current
INV=2V, CS=0V,
-
VDD=VDDG=18V
5
2
20 uA
3 mA
UVLO(ON)
VDD Under Voltage Lockout Enter VDD falling
8.2 9.0 10.5 V
UVLO(OFF)
VDD Under Voltage Lockout Exit VDD rising
13.5 14.8 16.0 V
VDD_clamp
OVP
Maximum VDD operation voltage IDD=10mA
Over voltage protection Threshold
Ramp VDD until gate
shut down
27 28.5 30
26 27.5 29
V
V
Current Sense Input Section
TLEB
LEB time
625 ns
Vth_oc
Over current threshold
880 910 940 mV
Td_oc
OCP Propagation delay
110 ns
ZSENSE_IN
T_ss
Input Impedance
Soft start time
50
17
Kohm
ms
Frequency Section
Freq_MaxNote 1 IC Maximum frequency
55 60 65 KHz
Freq_Nom
System Nominal switch frequency
50 KHz
Freq_startup
INV=0V, Comp=5V
14 KHz
f/Freq
Frequency shuffling range
+/-6 %
Error Amplifier section
Vref_EA
Reference voltage for EA
1.97 2
2.03 V
Gain
DC gain of EA
60 dB
I_COMP_MAX
Max. Cable compensation
current
INV=2V, Comp=0V
37.5
uA
Power MOSFET Section
BVdss
MOSFET Drain-Source
Breakdown Voltage
600 V
Rdson
On Resistance
Static, Id=0.45A
10 Ώ
Note:
1. Freq_Max indicates IC internal maximum clock frequency. In system application, the maximum operation frequency of 60Khz
nominal occurs at maximum output power or the transition point from CV to CC.
©On-Bright Electronics
Confidential
-5-
Preliminary Datasheet
OB_DOC_DS_253600