LM4140CCMX-4.1/NOPB [NSC]
IC 1-OUTPUT THREE TERM VOLTAGE REFERENCE, 4.096 V, PDSO8, SOIC-8, Voltage Reference;
| 型号： | LM4140CCMX-4.1/NOPB |
| 厂家： | 
National Semiconductor |
| 描述： | IC 1-OUTPUT THREE TERM VOLTAGE REFERENCE, 4.096 V, PDSO8, SOIC-8, Voltage Reference 光电二极管 输出元件 |
| 文件： | 总15页 (文件大小：870K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
February 2005
LM4140
High Precision Low Noise Low Dropout Voltage
Reference
General Description
Features
n High initial accuracy: 0.1%
n Ultra low noise
The LM4140 series of precision references are designed to
combine high accuracy, low drift and noise with low power
dissipation in a small package.
n Low Temperature Coefficient: 3 ppm/˚C (A grade)
n Low voltage operation: 1.8V
n SO-8 package
The LM4140 is the industry’s first reference with output
voltage options lower than the bandgap voltage.
@
The key to the advance performance of the LM4140 is the
use of EEPROM registers and CMOS DACs for temperature
coefficient curvature correction and trimming of the output
voltage accuracy of the device during the final production
testing.
n Low dropout voltage: 20 mV (typ) 1mA
n Supply Current: 230 µA (typ), ≤ 1 µA disable mode
n Enable pin
n Output voltage options: 1.024V, 1.250V, 2.048V, 2.500V,
and 4.096V
The major advantage of this method is the much higher
resolution available with DACs than is available economi-
cally with most methods utilized by other bandgap refer-
ences.
n Custom voltages from 0.5V to 4.5V
n Temperature range (0˚C to 70˚C)
Applications Summary
n Portable, battery powered equipment
n Instrumentation and test equipment
n Automotive
n Industrial process control
n Data acquisition systems
n Medical equipment
The low input and dropout voltage, low supply current and
output drive capability of the LM4140 makes this product an
ideal choice for battery powered and portable applications.
The LM4140 is available in three grades (A, B, C) with 0.1%
initial accuracy and 3, 6 and 10 ppm/˚C temperature coeffi-
cients. For even lower Tempco, contact National Semicon-
ductor.
n Precision scales
n Servo systems
n Battery charging
The device performance is specified over the temperature
range (0˚C to +70˚C) and is available in compact 8-pin SO
package.
For other output voltage options from 0.5V to 4.5V, con-
tact National Semiconductor.
Typical Application
Typical Temperature Coefficient
(Sample of 5 Parts)
10107901
C
, Output bypass capacitor. See text for selection detail.
OUT
10107923
Refer to the Ordering Information Table in this Data Sheet for Specific Part
Number
© 2005 National Semiconductor Corporation
DS101079
www.national.com
Ordering Information Temperature Range
(0˚C to 70˚C)
Initial Output Voltage Accuracy
LM4140 Supplied as 95 Units,
LM4140 Supplied as 2500
Units, Tape and Reel
@
25˚C
Tape and Reel
and Temperature Coefficient
LM4140ACM-1.0
LM4140ACM-1.2
LM4140ACM-2.0
LM4140ACM-2.5
LM4140ACM-4.1
LM4140BCM-1.0
LM4140BCM-1.2
LM4140BCM-2.0
LM4140BCM-2.5
LM4140BCM-4.1
LM4140CCM-1.0
LM4140CCM-1.2
LM4140CCM-2.0
LM4140CCM-2.5
LM4140CCM-4.1
LM4140ACMX-1.0
LM4140ACMX-1.2
LM4140ACMX-2.0
LM4140ACMX-2.5
LM4140ACMX-4.1
LM4140BCMX-1.0
LM4140BCMX-1.2
LM4140BCMX-2.0
LM4140BCMX-2.5
LM4140BCMX-4.1
LM4140CCMX-1.0
LM4140CCMX-1.2
LM4140CCMX-2.0
LM4140CCMX-2.5
LM4140CCMX-4.1
0.1%, 3 ppm/˚C max (A grade)
0.1%, 6 ppm/˚C max (B grade)
0.1%, 10 ppm/˚C max (C grade)
Connection Diagram
8-Lead Surface Mount (M)
10107902
Top View
See NS Package Number M08A
Pin Functions
Vref (Pin 6):
Reference Output. Capable of sourcing up to 8mA.
Positive Supply.
Input (Pin 2):
Ground (Pins 1, 4, 7, 8):
Negative Supply or Ground Connection. These pins must be
connected to ground.
Enable (Pin 3):
NC (Pin 5):
Pulled to input for normal operation. Forcing this pin to ground will
turn-off the output.
This pin must be left open.
www.national.com
2
Absolute Maximum Ratings (Note 1)
Lead Temperature:
Soldering, (10 sec.)
+260˚C
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Operating Range (Note 1)
Storage Temperature Range
Ambient Temperature Range
Junction Temperature Range
Maximum Voltage on any Input pin
Output Short-Circuit Duration
Power Dissipation (TA = 25˚C) (Note
2)
−0.3V to 5.6V
Indefinite
−65˚C to +150˚C
0˚C to 70˚C
0˚C to 80˚C
345mW
ESD Susceptibility (Note 3)
Human Body Model
2 kV
Machine Model
200V
LM4140
Electrical Charateristics
Unless otherwise specified, VIN = 3.0V for the LM4140-1.024 and LM4140-1.250, VIN = 5.0V for all other voltage options, VEN
= VIN. COUT = 1µF (Note 4), ILOAD = 1mA, TA = TJ = 25˚C. Limits with standard typeface are for TA = 25˚C, and limits in bold-
face type apply over 0˚C to 70˚C temperature range.
Min
(Note 6)
Typ
(Note 5)
Max
(Note 6)
Symbol
Parameter
Conditions
Units
Output Voltage Initial
Accuracy (Note 7)
LM4140B-1.024
LM4140B-1.250
LM4140B-2.048
LM4140B-2.500
LM4140B-4.096
LM4140C-1.024
LM4140C-1.250
LM4140C-2.048
LM4140C-2.500
LM4140C-4.096
Temperature Coefficient:
A Grade
0.1
0.1
VREF
%
TCVREF/˚C
0˚C ≤ TA ≤ + 70˚C
ppm/˚C
3
6
10
B Grade
C Grade
Line Regulation
1.024V and 1.250V options
1.8V ≤ VIN ≤ 5.5V
50
20
300
350
200
250
∆VREF/∆VIN
ppm/V
All other voltage options
Vref + 200mV ≤ VIN ≤
5.5V
Load Regulation
1 mA ≤ ILOAD ≤ 8mA
All other voltage options
1
5
20
150
35
∆VREF/∆ILOAD
ppm/mA
4.096V Option
150
∆VREF
∆VREF
Long-Term Stability
1000 Hrs
60
20
ppm
ppm
Thermal Hysteresis (Note 8)
0˚C ≤ TA ≤ + 70˚C
3
www.national.com
LM4140
Electrical Charateristics (Continued)
Unless otherwise specified, VIN = 3.0V for the LM4140-1.024 and LM4140-1.250, VIN = 5.0V for all other voltage options, VEN
= VIN. COUT = 1µF (Note 4), ILOAD = 1mA, TA = TJ = 25˚C. Limits with standard typeface are for TA = 25˚C, and limits in bold-
face type apply over 0˚C to 70˚C temperature range.
Min
(Note 6)
1.8
Typ
(Note 5)
Max
(Note 6)
5.5
Symbol
Parameter
LM4140-1.024,
Conditions
Units
Operating
Voltage
IL = 1 mA to 8 mA
V
LM4140-1.250
Dropout Voltage (Note 9)
LM4140-2.048,
IL = 1 mA
20
160
20
40
45
LM4140-2.500
IL = 8 mA
235
400
40
VIN-VREF
mV
LM4140-4.096
IL = 1 mA
45
IL = 8 mA
195
2.2
270
490
VN
Output Noise Voltage (Note
10)
0.1 Hz to 10 Hz
ILOAD = 0 mA
µVPP
IS(ON)
Supply Current
All other voltage options
230
265
.01
2
320
375
350
400
1
µA
4.096V Option
<
IS(OFF)
VH
Supply Current
VEnable 0.4V
µA
V
Logic High Input Voltage
Logic High Input Current
Logic Low Input Voltage
Logic Low Input Current
Short Circuit Current
0.8VIN
IH
nA
V
VL
0.4
IL
1
nA
mA
ISC
8.5
20
35
40
Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is
intended to be functional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see Electrical Characteristics. The
guaranteed specifications apply only for the test conditions listed. Some performance characteristics may degrade when the device is not operated under the listed
test conditions.
Note 2: Without PCB copper enhancements. The maximum power dissipation must be de-rated at elevated temperatures and is limited by T
(maximum
JMAX
junction temperature), θ (junction to ambient thermal resistance) and T (ambient temperature). The maximum power dissipation at any temperature is: PDiss
J-A
A
MAX
= (T
− T )/θ
up to the value listed in the Absolute Maximum Ratings. The θ
for the SO-8 package is 160˚C/W.
J-A
JMAX
A
J-A
Note 3: The human body model is a 100 pF capacitor discharged through a 1.5 kΩ resistor into each pin. The machine model is a 200 pF capacitor discharged
directly into each pin.
Note 4: For proper operation, a 1µF capacitor is required between the output pin and the GND pin of the device. (See Application Section for details)
Note 5: Typical numbers are at 25˚C and represent the most likely parametric norm.
Note 6: Limits are 100% production tested at 25˚C. Limits over the operating temperature range are guaranteed through correlation using Statistical Quality Control
(SQC) methods. The limits are used to calculate National’s Average Outgoing Quality Level (AOQL).
Note 7: High temperature and mechanical stress associated with PCB assembly can have significant impact on the initial accuracy of the LM4140 and may create
significant shifts in V
. See Application Hints section regarding accuracy and PCB layout consideration.
REF
Note 8: Thermal hysteresis is defined as the changes in +25˚C output voltage before and after the cycling of the device from 0˚C to 70˚C.
Note 9: Dropout voltage is defined as the minimum input to output differential voltage at which the output voltage drops by 0.5% below the value measured with
V
= 3.0V for the LM4140-1.024 and LM4140-1.250, V = 5.0V for all other voltage options.
IN
IN
Note 10: The output noise is based on 1.024V option. Output noise is linearly proportional to V
.
REF
www.national.com
4
LM4140 Typical Performance Characteristics
Unless otherwise specified, TA = 25˚C, No Load, COUT
1µF, VIN = 3.0V for LM4140-1.024 and LM4140-1.250, and
5V for all other voltage options. VIN = VEN
=
.
Power Up/Down Ground Current
Enable Response
10107905
10107906
* The 1µF output capacitor is actively discharged to ground.
See ON/OFF Operation section for more details.
Line Transient Response
Load Transient Response
10107908
10107907
5
www.national.com
LM4140 Typical Performance Characteristics Unless otherwise specified, TA = 25˚C, No Load,
COUT = 1µF, VIN = 3.0V for LM4140-1.024 and LM4140-1.250, and 5V for all other voltage options. VIN = VEN. (Continued)
Output Impedance
Power Supply Rejection Ratio
10107910
10107909
Dropout Voltage vs Load Current
Output Voltage Change vs Sink Current (ISINK)
10107911
10107912
Note: 1.024V and 1.250V options require 1.8V supply.
www.national.com
6
LM4140 Typical Performance Characteristics Unless otherwise specified, TA = 25˚C, No Load,
COUT = 1µF, VIN = 3.0V for LM4140-1.024 and LM4140-1.250, and 5V for all other voltage options. VIN = VEN. (Continued)
Total Current (IS(OFF)) vs Supply Voltage
Total Current (IS(ON)) vs Supply Voltage
10107913
10107914
Spectral Noise Density (0.1Hz to 10Hz)
Spectral Noise Density (10Hz to 100kHz)
10107931
10107932
Ground Current vs Load Current
Long Term Drift
10107938
10107939
7
www.national.com
LM4140 Typical Performance Characteristics Unless otherwise specified, TA = 25˚C, No Load,
COUT = 1µF, VIN = 3.0V for LM4140-1.024 and LM4140-1.250, and 5V for all other voltage options. VIN = VEN. (Continued)
Load Regulation vs Temperature
Output Voltage vs Load Current
10107941
10107940
Line Regulation vs Temperature
IQ vs Temperature
10107942
10107943
Short Circuit Current vs Temperature
Dropout Voltage vs Load Current (VOUT) = 2.0V
10107944
10107945
www.national.com
8
Application Hints
INPUT CAPACITORS
Although not always required, an input capacitor is recom-
mended. A supply bypass capacitor on the input assures that
the reference is working from a source with low impedance,
which improves stability. A bypass capacitor can also im-
prove transient response by providing a reservoir of stored
energy that the reference can utilize in case where the load
current demand suddenly increases. The value used for CIN
may be used without limit. Refer to the typical application
section for examples of input capacitors.
OUTPUT CAPACITORS
The LM4140 requires a 1µF (nominally) output capacitor for
loop stability (compensation) as well as transient response.
During the sudden changes in load current demand, the
output capacitor must source or sink current during the time
it takes the control loop of the LM4140 to respond.
10107930
FIGURE 3. 10 µF ESR Range
TANTALUM CAPACITORS
This capacitor must be selected to meet the requirements of
minimum capacitance and equivalent series resistance
(ESR) range.
Surface-mountable solid tantalum capacitors offer a good
combination of small physical size for the capacitance value,
and ESR in the range needed for by the LM4140. The results
of testing the LM4140 stability with surface mount solid
tantalum capacitors show good stability with values in the
range of 0.1µF. However, optimum performance is achieved
with a 1µF capacitor.
In general, the capacitor value must be at least 0.2µF (over
the actual ambient operating temperature), and the ESR
must be within the range indicated in Figure 1, Figure 2 and
Figure 3.
Tantalum capacitors that have been verified as suitable for
use with the LM4140 are shown in Table 1.
TABLE 1. Surface-Mount Tantalum Capacitor Selection
Guide
1µF Surface-Mount Tantalums
Manufacturer
Kemet
Part Number
T491A105M010AS
NRU105N10
NEC
Siemens
Nichicon
Sprague
B45196-E3105-K
F931C105MA
293D105X0016A2T
10107928
2.2µF Surface-Mount Tantalums
FIGURE 1. 0.22 µF ESR Range
Kemet
NEC
T491A225M010AS
NRU225M06
Siemens
Nichicon
Sprague
B45196/2.2/10/10
F930J225MA
293D225X0010A2T
ALUMINUM ELECTROLYTIC CAPACITORS
Although probably not a good choice for a production design,
because of relatively large physical size, an aluminium elec-
trolytic capacitor can be used in the design prototype for an
LM4140 reference. A 1µF capacitor meeting the ESR condi-
tions can be used. If the operating temperature drops below
0˚C, the reference may not remain stable, as the ESR of the
aluminium electrolytic capacitor will increase, and may ex-
ceed the limits indicated in the figures.
10107929
FIGURE 2. 1 µF ESR Range
9
www.national.com
the LM4140 input voltage, but must remain within the Abso-
lute Maximum Rating for the enable pin.
Application Hints (Continued)
MULTILAYER CERAMIC CAPACITORS
OUTPUT ACCURACY
Surface-mountable multilayer ceramic capacitors may be an
attractive choice because of their relatively small physical
size and excellent RF characteristics.
Like all references, either series or shunt, the after assembly
accuracy is made up of primarily three components: initial
accuracy itself, thermal hysteresis and effects of the PCB
assembly stress.
However, they sometimes have an ESR values lower than
the minimum required by the LM4140, and relatively large
capacitance change with temperature. The manufacturer’s
datasheet for the capacitor should be consulted before se-
lecting a value. Test results of LM4140 stability using multi-
layer ceramic capacitors show that a minimum of 0.2µF is
usually needed.
LM4140 provides an excellent output initial accuracy of 0.1%
and temperature coefficient of 6ppm/˚C (B Grade).
For best accuracy and precision, the LM4140 junction tem-
perature should not exceed 70˚C.
The thermal hysteresis curve on this datasheet are perfor-
mance characteristics of three typical parts selected at ran-
dom from a sample of 40 parts.
Multilayer ceramic capacitors that have been verified as
suitable for use with the LM4140 are shown in Table 2.
Parts are mounted in a socket to minimize the effect of
PCB’s mechnical expansion and contraction. Readings are
taken at 25˚C following multiple temperature cycles to 0˚C
and 70˚C. The labels on the X axis of the graph indicates the
device temperature cycle prior to measurement at 25˚C.
TABLE 2. Surface-Mount Ceramic Capacitors Selection
Guide
2.2µF Surface-Mount Ceramic
Manufacturer
Tokin
Part Number
1E225ZY5U-C203
GRM42-6Y5V225Z16
Murata
4.7µF Surface-Mount Ceramic
Tokin
1E475ZY5U-C304
REVERSE CURRENT PATH
The P-channel Pass transistor used in the LM4140 has an
inherent diode connected between the VIN and VREF pins
(see diagram below).
10107933
10107903
FIGURE 4. Typical Thermal Hysteresis
Forcing the output to voltages higher than the input, or
pulling VIN below voltage stored on the output capacitor by
more than a Vbe, will forward bias this diode and current will
flow from the VREF terminal to VIN. No damage to the
LM4140 will occur under these conditions as long as the
current flowing into the output pin does not exceed 50mA.
The mechanical stress due to the PCB’s mechanical and
thermal stress can cause an output voltage shift more than
the true thermal coefficient of the device. References in
surface mount packages are more susceptible to these
stresses because of the small amount of plastic molding
which support the leads.
ON/OFF OPERATION
Following the recommendations on PCB Layout Consider-
ation section can minimize the mechanical stress on the
device.
The LM4140 is designed to quickly reduce both VREF and IQ
to zero when turned-off. VREF is restored in less than 200µs
when turned-on. During the turn-off, the charge across the
output capacitor is discharged to ground through internal
circuitry.
PCB LAYOUT CONSIDERATION
The simplest ways to reduce the stress related shifts are:
The LM4140 is turned-off by pulling the enable input low, and
turned-on by driving the input high. If this feature is not to be
used, the enable pin should be tied to the VIN to keep the
reference on at all times (the enable pin must not be left
floating).
1. Mounting the device near the edges or the corners of the
board where mechanical stress is at its minimum. The
center of the board generally has the highest mechani-
cal and thermal expansion stress.
2. Mechanical isolation of the device by creating an island
by cutting a U shape slot on the PCB for mounting the
device. This approach would also provide some thermal
isolation from the rest of the circuit.
To ensure proper operation, the signal source used to drive
the enable pin must be able to swing above and below the
specified high and low voltage thresholds which guarantee
an ON or OFF state (see Electrical Characteristics).
Figure 5 is a recommended printed board layout with a slot
cut on three sides of the circuit layout to serve as a strain
relief.
The ON/OFF signal may come from either a totem-pole
output, or an open-collector output with pull-up resistor to the
LM4140 input voltage. This high-level voltage may exceed
www.national.com
10
Application Hints (Continued)
10107935
10107934
FIGURE 5. Suggested PCB Layout with Slot
11
www.national.com
Typical Application Circuits
Voltage Reference with Force and Sense Output
Boosted Output Current
10107920
Precision Programmable Current Source
10107915
Boosted Ouput Current with Current Limiter
10107921
Precision DAC Reference
10107922
Complimentary Outputs
10107936
10107919
* Low Noise Op Amp such as OP-27
www.national.com
12
Typical Application Circuits (Continued)
Strain Gauge Conditioner for 350Ω Bridge
10107937
10107926
FIGURE 6.
13
www.national.com
Typical Application Circuits (Continued)
10107927
FIGURE 7.
www.national.com
14
Physical Dimensions inches (millimeters) unless otherwise noted
SO-8 Package Type M
NS Package Number M08A
National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves
the right at any time without notice to change said circuitry and specifications.
For the most current product information visit us at www.national.com.
LIFE SUPPORT POLICY
NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS
WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR
CORPORATION. As used herein:
1. Life support devices or systems are devices or systems
which, (a) are intended for surgical implant into the body, or
(b) support or sustain life, and whose failure to perform when
properly used in accordance with instructions for use
provided in the labeling, can be reasonably expected to result
in a significant injury to the user.
2. A critical component is any component of a life support
device or system whose failure to perform can be reasonably
expected to cause the failure of the life support device or
system, or to affect its safety or effectiveness.
BANNED SUBSTANCE COMPLIANCE
National Semiconductor manufactures products and uses packing materials that meet the provisions of the Customer Products
Stewardship Specification (CSP-9-111C2) and the Banned Substances and Materials of Interest Specification (CSP-9-111S2) and contain
no ‘‘Banned Substances’’ as defined in CSP-9-111S2.
National Semiconductor
Americas Customer
Support Center
National Semiconductor
Europe Customer Support Center
Fax: +49 (0) 180-530 85 86
National Semiconductor
Asia Pacific Customer
Support Center
National Semiconductor
Japan Customer Support Center
Fax: 81-3-5639-7507
Email: new.feedback@nsc.com
Tel: 1-800-272-9959
Email: europe.support@nsc.com
Deutsch Tel: +49 (0) 69 9508 6208
English Tel: +44 (0) 870 24 0 2171
Français Tel: +33 (0) 1 41 91 8790
Email: ap.support@nsc.com
Email: jpn.feedback@nsc.com
Tel: 81-3-5639-7560
www.national.com
相关型号：
LM422-100.00M
LVDS Output Clock Oscillator, 100MHz Nom, ROHS COMPLIANT, HERMETIC SEALED, CERAMIC PACKAGE-6
CONNOR-WINFIE
LM422-670.00M
LVDS Output Clock Oscillator, 670MHz Nom, ROHS COMPLIANT, HERMETIC SEALED, CERAMIC PACKAGE-6
CONNOR-WINFIE
©2020 ICPDF网 联系我们和版权申明