To learn more about ON Semiconductor, please visit our website at
www.onsemi.com
Please note: As part of the Fairchild Semiconductor integration, some of the Fairchild orderable part numbers
will need to change in order to meet ON Semiconductor’s system requirements. Since the ON Semiconductor
product management systems do not have the ability to manage part nomenclature that utilizes an underscore
(_), the underscore (_) in the Fairchild part numbers will be changed to a dash (-). This document may contain
device numbers with an underscore (_). Please check the ON Semiconductor website to verify the updated
device numbers. The most current and up-to-date ordering information can be found at www.onsemi.com. Please
email any questions regarding the system integration to Fairchild_questions@onsemi.com.
Is Now Part of
ON Semiconductor and the ON Semiconductor logo are trademarks of Semiconductor Components Industries, LLC dba ON Semiconductor or its subsidiaries in the United States and/or other countries. ON Semiconductor owns the rights to a number
of patents, trademarks, copyrights, trade secrets, and other intellectual property. A listing of ON Semiconductor’s product/patent coverage may be accessed at www.onsemi.com/site/pdf/Patent-Marking.pdf. ON Semiconductor reserves the right
to make changes without further notice to any products herein. ON Semiconductor makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does ON Semiconductor assume any liability
arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages. Buyer is responsible for its products and applications using ON
Semiconductor products, including compliance with all laws, regulations and safety requirements or standards, regardless of any support or applications information provided by ON Semiconductor. “Typical” parameters which may be provided in ON
Semiconductor data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including “Typicals” must be validated for each customer application by customer’s
technical experts. ON Semiconductor does not convey any license under its patent rights nor the rights of others. ON Semiconductor products are not designed, intended, or authorized for use as a critical component in life support systems or any FDA
Class 3 medical devices or medical devices with a same or similar classification in a foreign jurisdiction or any devices intended for implantation in the human body. Should Buyer purchase or use ON Semiconductor products for any such unintended
or unauthorized application, Buyer shall indemnify and hold ON Semiconductor and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out
of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that ON Semiconductor was negligent regarding the design or manufacture of the part. ON Semiconductor
is an Equal Opportunity/Affirmative Action Employer. This literature is subject to all applicable copyright laws and is not for resale in any manner.
©2002 Fairchild Semiconductor Corporation
www.fairchildsemi.com
Rev. 1.0.1
Features
•5V ±1% Reference
• Oscillator Sync Terminal
• Internal Soft Start
• Deadtime Control
• Und e r Voltage Lo ck out
Description
The KA3525A is a monolithic integrated circuit that
includes all of the control circuits necessary for a pulse width
modulating regulator. There are a voltage reference, an error
amplifier , a pulse width modulator, an oscillator, an under
voltage lockout, a soft start circuit, and the output driver in
the chip.
16-DIP
1
Internal Block Diagram
16
15
12
1
2
9
8
10 5
7
364
14
11
13
U.V.L.O.
BAND GAP
REF 5V
LATCH
SR
F/F Q
Q
5K
VC
OUTPUT A
OUTPUT B
OSCILLATOR
DISCHARGE
5K
ERR
AMP
PWM
COMP
_
+
_
+
CT
VREF
VCC
GND
EA(-)
EA(+)
EAOUT
C
(SOFT
START)
SHUT DOWN
SYNC RTOSC
OUTPUT
KA3525A
SMPS Controller
KA3525A
2
Absolute Maximum Ratings
Electrical Characteristics
(VCC = 20V, TA = 0 to +70°C, unless otherwise specified)
Parameter Symbol Value Unit
Supply Voltage VCC 40 V
Collector Supply Voltage VC40 V
Output Current, Sink or Source IO500 mA
Reference Output Current IREF 50 mA
Oscillator Charging Current ICHG(OSC) 5mA
Power Dissipation (TA = 25°C) PD1000 m/W
Operating Temperature TOPR 0 ~ +70 °C
Storage Temperature TSTG -65 ~ +150 °C
Lead Temperature (Soldering, 10sec) TLEAD +300 °C
Parameter Symbol Conditions Min. Typ. Max. Unit
REFERENCE SECTION
Reference Output Voltage VREF TJ = 25°C5.05.15.2V
Line Regulation ∆VREF VCC = 8 to 35V - 9 20 mV
Load Regulation ∆VREF IREF = 0 to 20mA - 20 50 mV
Short Circuit Output Current ISC VREF = 0, TJ = 25°C - 80 100 mA
Total Output Variation (Note1) ∆VREF Line, Load and Temperature 4.95 - 5.25 V
Temperature Stability (Note1) STT--2050mV
Long Term Stability (Note1) ST TJ = 125°C ,1KHRS-2050mV
OSCILLATOR SECTION
Initial Accuracy (Note1, 2) ACCUR TJ = 25°C-±3±6%
Frequency Change With Voltage ∆f/∆VCC VCC = 8 to 35V (Note1, 2) - ±0.8 ±2%
Maximum Frequency f(MAX) RT = 2kΩ, CT = 470pF 400 430 - kHz
Minimum Frequency f(MIN) RT = 200kΩ, CT = 0.1uF - 60 120 Hz
Clock Amplitude (Note1, 2) V(CLK) -34-V
Clock Width (Note1, 2) tW(CLK) TJ = 25°C0.30.61µs
Sync Threshold VTH(SYNC) -1.2 2 2.8 V
Sync Input Current II(SYNC) Sync = 3.5V - 1.3 2.5 mA
KA3525A
3
Electrical Characteristics (Continued)
(VCC = 20V, TA = 0 to +70°C, unless otherwise specified)
Note :
1. These parameters . although guaranteed over the recommended operating conditions, are not 100% tested in production
2. Te sted at fOSC=40kHz (RT =3.6K, CT =0.01uF, RI = 0Ω)
Parameter Symbol Conditions Min. Typ. Max. Unit
ERROR AMPLIFIER SECTION (VCM = 5.1V)
Input Offset Voltage VIO --1.510mV
Input Bias Current IBIAS --110µA
Input Offset Current IIO --0.11µA
Open Loop Voltage Gain GVO RL ≥ 10MΩ60 80 - dB
Common Mode Rejection Ratio CMRR VCM = 1.5 to 5.2V 60 90 - dB
Power Supply Rejection Ratio PSRR VCC = 8 to 3.5V 50 60 - dB
PWM COMPARATOR SECTION
Minimum Duty Cycle D(MIN) ---0%
Maximum Duty Cycle D(MAX) -45 49 - %
Input Threshold Voltage (Note2) VTH1 Zero Duty Cycle 0.7 0.9 - V
Input Threshold Voltage (Note2) VTH2 Max Duty Cycle - 3.2 3.6 V
SOFT-START SECTION
Soft Start Current ISOFT VSD = 0V, VSS = 0V 25 51 80 µA
Soft Start Low Level Voltage VSL VSD = 25V - 0.3 0.7 V
Shutdown Threshold Voltage VTH(SD) -0.9 1.3 1.7 V
Shutdown Input Current IN(SD) VSD = 2.5V - 0.3 1 mA
OUTPUT SECTION
Low Output Voltage I VOL I ISINK = 20mA - 0.1 0.4 V
Low Output Voltage II VOL II ISINK = 100mA - 0.05 2 V
High Output Voltage I VCH I ISOURCE = 20mA 18 19 - V
High Output Voltage II VCH II ISOURCE = 100mA 17 18 - V
Under Voltage Lockout VUV V8 and V9 = High 678V
Collector Leakage Current ILKG VCC = 35V - 8 0 200 µA
Rise Time (Note1) tRCL = 1uF, TJ = 25°C - 80 600 ns
Fall Time (Note1) tFCL = 1uF, TJ = 25°C - 70 300 ns
STANDBY CURRENT
Supply Current ICC VCC = 35V - 12 20 mA
KA3525A
4
Test Circuit
16
15
12
1
2
9
8
10
57
13
11
14
36
BAND GAP
REF 5V U.V.L.O.
A
B
0.1
Vcc 0.1
3k
RWM
ADJ
10k
1.5K
10K
0.01
5.0uF
5.0k
5.0k 5.0k
100
F/F
ERR
AMP ERR
AMP
OSCILLATOR
LATCH
SS R
SOFT START +
SHUTDOWN
VREF
CT
RAMP
0.009 0.1
+
3.6k
0.001
DEAD
TIME
OUT B
10k
10k
OUT A
VC
CLOCK
_
++
_
RT
KA3525A
5
Mechanical Dimensions
Package
#1
#8 #9
#16
6.40
±0.20
7.62
0.300
2.54
0.100
0.252
±0.008
0~15°
0.25
+0.10
–0.05
0.010
+0.004
–0.002
3.30
±0.30
0.130
±0.012
3.25
±0.20
0.128
±0.008
19.40
±0.20
0.764
±0.008
19.80
0.780 MAX
5.08
0.200
0.38
0.014
MAX
MIN
0.81
0.032
()
0.46
±0.10
0.018
±0.004
0.059
±0.004
1.50
±0.10
16-DIP
KA3525A
10/2/02 0.0m 001
Stock#DSxxxxxxxx
2002 Fairchild Semiconductor Corporation
LIFE SU PP ORT POLICY
FAIRCHILD’S PRODUCTS AR E NOT AUTHORIZED FOR USE AS CRITICAL COMP ONENTS IN L IFE SUPPOR T DEVICES
OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD SEMICONDUCTOR
CORPORA TION. As used herein:
1. Life support devices or systems are devices or systems
which, (a ) are intended for surgical im plant into the body,
or (b) support or sustain life, and (c) whose failure to
perform when properly used in accordance with
instructions for use provided in the labeling, can be
reasonab ly expected to result in a significant injury of the
user.
2. A critical component in any component of a life support
device or system whose failure to perfo rm can be
reasonably expected to cause the failure of the life support
device or system, or to affect its safety or effec tiveness.
www.fairchildsemi.com
DISCLAIMER
FAIRCHILD SEMI CONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY
PRO DUCTS HEREI N TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILD DO ES NOT ASSUME ANY
LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN; NEITHER
DOES IT CONVEY A NY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OT HERS.
Ordering Information
Product Number Package Operating Temperature
KA3525A 16-DIP 0 ~ +70°C
www.onsemi.com
1
ON Semiconductor and are trademarks of Semiconductor Components Industries, LLC dba ON Semiconductor or its subsidiaries in the United States and/or other countries.
ON Semiconductor owns the rights to a number of patents, trademarks, copyrights, trade secrets, and other intellectual property. A listing of ON Semiconductor’s product/patent
coverage may be accessed at www.onsemi.com/site/pdf/Patent−Marking.pdf. ON Semiconductor reserves the right to make changes without further notice to any products herein.
ON Semiconductor makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does ON Semiconductor assume any liability
arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages.
Buyer is responsible for its products and applications using ON Semiconductor products, including compliance with all laws, regulations and safety requirements or standards,
regardless of any support or applications information provided by ON Semiconductor. “Typical” parameters which may be provided in ON Semiconductor data sheets and/or
specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including “Typicals” must be validated for each customer
application by customer’s technical experts. ON Semiconductor does not convey any license under its patent rights nor the rights of others. ON Semiconductor products are not
designed, intended, or authorized for use as a critical component in life support systems or any FDA Class 3 medical devices or medical devices with a same or similar classification
in a foreign jurisdiction or any devices intended for implantation in the human body. Should Buyer purchase or use ON Semiconductor products for any such unintended or unauthorized
application, Buyer shall indemnify and hold ON Semiconductor and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and
expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such
claim alleges that ON Semiconductor was negligent regarding the design or manufacture of the part. ON Semiconductor is an Equal Opportunity/Affirmative Action Employer. This
literature is subject to all applicable copyright laws and is not for resale in any manner.
PUBLICATION ORDERING INFORMATION
N. American Technical Support: 800−282−9855 Toll Free
USA/Canada
Europe, Middle East and Africa Technical Support:
Phone: 421 33 790 2910
Japan Customer Focus Center
Phone: 81−3−5817−1050
www.onsemi.com
LITERATURE FULFILLMENT:
Literature Distribution Center for ON Semiconductor
19521 E. 32nd Pkwy, Aurora, Colorado 80011 USA
Phone: 303−675−2175 or 800−344−3860 Toll Free USA/Canada
Fax: 303−675−2176 or 800−344−3867 Toll Free USA/Canada
Email: orderlit@onsemi.com
ON Semiconductor Website: www.onsemi.com
Order Literature: http://www.onsemi.com/orderlit
For additional information, please contact your local
Sales Representative
© Semiconductor Components Industries, LLC
