UC3965DTR [TI]
Precision Reference with Low Offset Error Amplifier 8-SOIC 0 to 70;
| 型号： | UC3965DTR |
| 厂家： | 
TEXAS INSTRUMENTS |
| 描述： | Precision Reference with Low Offset Error Amplifier 8-SOIC 0 to 70 光电二极管 |
| 文件： | 总6页 (文件大小：76K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
application
INFO
UC1965
UC2965
UC3965
available
Precision Reference with Low Offset Error Amplifier
FEATURES
DESCRIPTION
• Accessible 2.5V Precision Reference
The UC3965 is suitable for applications needing greater precision and
more functionality than the TL431 type shunt regulators. The wide range
VCC input capability enables the device to be biased from the secondary
side output voltage rail, resulting in closed loop soft start.
• 0.4% Initial Reference Accuracy
• 1% Reference Accuracy over Line,
Load, and Full Temperature Range
The UC3965 includes an accessible 2.5V precision reference which offers
0.4% initial and 1% reference accuracy over line, load, and full tempera-
ture range with a low offset error amplifier, a 2X inverting amplifier/buffer,
and an undervoltage lockout circuit. The IC is ideally suited for applica-
tions where high precision PWM power supply regulation is required.
Typically, the error amplifier is configured to compare a fraction of the to
be regulated power supply voltage to the on-chip 2.5V reference. The 2X
amplifier/buffer output is then used to drive a PWM controller or regulator.
The UC3965 is also capable of driving an optocoupler diode for isolated
applications.
• Low 1mV Offset Error Amplifier
• Supports Closed Loop Soft Start
• 2X Inverting Amplifier / Buffer Output
• 4.1V Undervoltage Lockout
• ICC 2mA at 5V
• 8-Pin SOIC or DIL Package
BLOCK DIAGRAM
OFFSET
VCC
1
2
8
7
6
5
COMP
VFB
VREF
2.5V
UVLO
5k
+
OB
–
VCC
5k
VOUT
GND
3
4
VREF
NI
–
EA
+
15k
7.5k
2k
UDG-98055
SLUS300A - APRIL 1999
UC1965
UC2965
UC3965
CONNECTION DIAGRAM
ABSOLUTE MAXIMUM RATINGS
VCC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3V to 20V
VREF. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3V to 6V
VFB, COMP, NI, VOUT. . . . . . . . . . . . . . . . . . . . . –0.3V TO 6V
Storage Temperature . . . . . . . . . . . . . . . . . . . −65°C to +150°C
Junction Temperature. . . . . . . . . . . . . . . . . . . –55°C to +150°C
Lead Temperature (Soldering, 10 sec.) . . . . . . . . . . . . . +300°C
DIL-8, SOIC-8 (Top View)
J or N Package, D Package
OFFSET
VCC
8
7
6
5
COMP
VFB
1
2
3
4
Currents are positive into, negative out of the specified terminal.
All voltages are with respect to ground. Consult Packaging Sec-
tion of Databook for thermal limitations and considerations of
packages.
VOUT
GND
VREF
NI
ORDERING INFORMATION
TEMPERATURE RANGE
–55°C to +125°C
PACKAGE
CDIP
UC1965J
UC2965D
UC2965N
UC3965D
UC3965N
–40°C to +85°C
SOIC
PDIP
SOIC
PDIP
0°C to +70°C
ELECTRICAL CHARACTERISTICS Unless otherwise specified, VCC = 5V, TA = TJ.
PARAMETER TEST CONDITIONS
MIN
TYP
MAX UNITS
General
VCC
4.3
1.5
20
4
V
Operating Current
VCC = 5V
2
mA
µA
V
Undervoltage Current
Minimum Voltage to Start
Hysteresis
200
4.3
400
3.9
4.1
200
300
mV
VREF
VREF Initial Accuracy
VREF Over Temperature
Total Output Variation
Line Regulation
+25°C
2.49
2.48
2.5
2.5
2.5
2
2.51
2.52
2.525
10
V
V
–55°C to +125°C
Line, Load, Temperature
VCC = 4.3V to 20V
0µA to 500µA
2.475
V
mV
mV
mA
Load Regulation
2
10
Short Circuit Current
Error Amplifier
VREF = 0V
2
Input Bias
VCM = 2.5V
200
1
400
2
nA
mV
nA
Input Offset Voltage
Input Offset Current
Gain Bandwidth Product
Open Loop Gain
VCM = 2.5V
VCM = 2.5V
–100
80
0
100
VIN = 50mV P-P (Note 1)
VOUT = 1V to 3.75V
6
MHz
dB
100
2
UC1965
UC2965
UC3965
ELECTRICAL CHARACTERISTICS Unless otherwise specified, VCC = 5V, TA = TJ.
PARAMETER
Error Amplifier Section (cont.)
Output Low Level
TEST CONDITIONS
MIN
TYP
MAX UNITS
IOUT = 0µA
IOUT = 100µA
IOUT = 0µA
0.8
1.2
4
V
V
Output High Level
V
IOUT = –500µA
4
V
Short Circuit Circuit
CMRR
VCOMP = 0V
8
mA
dB
dB
V/µs
V/µs
VCM = 1.25V to 3.75V
VCC = 4.3V to 20V
70
70
100
100
2
PSRR
Rising Slew Rate
Falling Slew Rate
Inverting Buffer Amplifier
Input Bias
0.4
VCM = 2.5V
1
0
2
µA
mV
MHz
V/V
V
Output Offset Voltage
Gain Bandwidth Product
Closed Loop Gain
Output Low Level
VCM = 2.5V
–20
20
VIN = 50mV P-P (Note 1)
Inverting Gain
IOUT = 0µA
IOUT = 100µA
IOUT = 0mA
1.5
–2
0.3
0.5
4
–2.04
–1.96
V
Output High Level
V
IOUT = –4mA
4
V
Short Circuit Circuit
CMRR
VOUT = 0V
18
100
100
0.9
0.9
mA
dB
dB
V/µs
V/µs
VCM = 1.25V to 3.75V
VCC = 4.3V to 20V
70
70
PSRR
Rising Slew Rate
Falling Slew Rate
Note 1: Guaranteed by design. Not 100% tested in production.
PIN DESCRIPTIONS
COMP: The output of the error amplifier and the input to VFB: The inverting terminal of the error amplifier used as
the inverting terminal of the internal output buffer. This both the voltage sense input to the error amplifier and its
pin is available to compensate the high frequency gain of other compensation point.
the error amplifier.
VOUT: The emitter of the output transistor. This pin is
the output of the inverting buffer. This pin has the capa-
bility to drive an optocoupler or a PWM controller directly.
GND: The reference and power ground for the device.
NI: The non-inverting input to the error amplifier.
VREF: The output of the trimmed precision reference.
This reference maintains within 1% of its initial value over
its entire line, load, and temperature range.
OFFSET: The non-inverting input to the internal output
buffer.
VCC: The power input to the device. The minimum to
maximum operating voltage is 4.3V to 20V.
3
UC1965
UC2965
UC3965
APPLICATION INFORMATION
For designs requiring input-output isolation, the UC3965 that insures accurate regulation of the output. The inter-
is used in secondary side output voltage sensing. As nal error amplifier drives the inverting input of the output
shown in Fig. 1, the precision reference and low offset buffer (OB) which drives an optocoupler diode. The wide
error amplifier can be used in converters, such as the range VCC voltage enables the device to be biased from
isolated flyback, where the primary side error amplifier is the secondary side output voltage rail, resulting in closed
not used or simply not present. In this case, the loop soft start.
UCC3809 is used as the primary side controller.
As the output voltage increases beyond its desired value,
The precision reference of the UC3965 is tied to the the voltage difference at the error amplifier increases.
non-inverting input of the device’s internal error amplifier. This results in less drive at the inverting input of the inter-
The output voltage of the converter is resistively divided nal buffer, increasing its output drive to the optocoupler.
and compared to this reference at the inverting input. If the application does not require input-output isolation,
This error amplifier has a low 1mV input offset voltage this buffer could be used to drive the PWM directly.
+V
OUT
OFFSET
VCC
COMP
1
2
3
8
VREF
2.5V
UVLO
5k
VOUT
+
OB
VFB
VREF
NI
–
VCC
5k
7
6
5
–
EA
+
15k
7.5k
GND
4
+V
IN
2k
UCC3809
1
FB
REF
8
7
–V
OUT
VDD
2
3
4
SS
RT1 OUT
RT2 GND
6
5
–V
IN
UDG-99080
Figure 1. Typical application diagram.
ADDITIONAL INFORMATION
For additional application information biasing the
UC3965, please refer to the following publication:
[1] Application Note U-165, Design Review: Isolated 50W
Flyback with the UCC3809 Primary Side Controller and
the UC3965 Precision Reference and Error Amplifier, by
Lisa Dinwoodie.
UNITRODE CORPORATION
7 CONTINENTAL BLVD. • MERRIMACK, NH 03054
TEL. (603) 424-2410 • FAX (603) 424-3460
4
PACKAGE OPTION ADDENDUM
www.ti.com
24-Jun-2005
PACKAGING INFORMATION
Orderable Device
Status (1)
Package Package
Pins Package Eco Plan (2) Lead/Ball Finish MSL Peak Temp (3)
Qty
Type
SOIC
SOIC
SOIC
SOIC
Drawing
UC2965D
UC2965DTR
UC3965D
OBSOLETE
OBSOLETE
OBSOLETE
OBSOLETE
D
D
D
D
8
8
8
8
TBD
TBD
TBD
TBD
Call TI
Call TI
Call TI
Call TI
Call TI
Call TI
Call TI
Call TI
UC3965DTR
(1) The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in
a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
Eco Plan
-
The planned eco-friendly classification: Pb-Free (RoHS) or Green (RoHS
&
no Sb/Br)
-
please check
http://www.ti.com/productcontent for the latest availability information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements
for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered
at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame
retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material)
(3)
MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder
temperature.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is
provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the
accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and continues to take
reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on
incoming materials and chemicals. TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited
information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI
to Customer on an annual basis.
Addendum-Page 1
IMPORTANT NOTICE
Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications,
enhancements, improvements, and other changes to its products and services at any time and to discontinue
any product or service without notice. Customers should obtain the latest relevant information before placing
orders and should verify that such information is current and complete. All products are sold subject to TI’s terms
and conditions of sale supplied at the time of order acknowledgment.
TI warrants performance of its hardware products to the specifications applicable at the time of sale in
accordance with TI’s standard warranty. Testing and other quality control techniques are used to the extent TI
deems necessary to support this warranty. Except where mandated by government requirements, testing of all
parameters of each product is not necessarily performed.
TI assumes no liability for applications assistance or customer product design. Customers are responsible for
their products and applications using TI components. To minimize the risks associated with customer products
and applications, customers should provide adequate design and operating safeguards.
TI does not warrant or represent that any license, either express or implied, is granted under any TI patent right,
copyright, mask work right, or other TI intellectual property right relating to any combination, machine, or process
in which TI products or services are used. Information published by TI regarding third-party products or services
does not constitute a license from TI to use such products or services or a warranty or endorsement thereof.
Use of such information may require a license from a third party under the patents or other intellectual property
of the third party, or a license from TI under the patents or other intellectual property of TI.
Reproduction of information in TI data books or data sheets is permissible only if reproduction is without
alteration and is accompanied by all associated warranties, conditions, limitations, and notices. Reproduction
of this information with alteration is an unfair and deceptive business practice. TI is not responsible or liable for
such altered documentation.
Resale of TI products or services with statements different from or beyond the parameters stated by TI for that
product or service voids all express and any implied warranties for the associated TI product or service and
is an unfair and deceptive business practice. TI is not responsible or liable for any such statements.
Following are URLs where you can obtain information on other Texas Instruments products and application
solutions:
Products
Applications
Audio
Amplifiers
amplifier.ti.com
www.ti.com/audio
Data Converters
dataconverter.ti.com
Automotive
www.ti.com/automotive
DSP
dsp.ti.com
Broadband
Digital Control
Military
www.ti.com/broadband
www.ti.com/digitalcontrol
www.ti.com/military
Interface
Logic
interface.ti.com
logic.ti.com
Power Mgmt
Microcontrollers
power.ti.com
Optical Networking
Security
www.ti.com/opticalnetwork
www.ti.com/security
www.ti.com/telephony
www.ti.com/video
microcontroller.ti.com
Telephony
Video & Imaging
Wireless
www.ti.com/wireless
Mailing Address:
Texas Instruments
Post Office Box 655303 Dallas, Texas 75265
Copyright 2005, Texas Instruments Incorporated
相关型号：
©2020 ICPDF网 联系我们和版权申明