データシートサーチシステム
  Japanese  ▼
ALLDATASHEET.JP

X  

LM134H データシート(PDF) 5 Page - Linear Technology

部品番号 LM134H
部品情報  Constant Current Source and Temperature Sensor
Download  12 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
メーカー  LINER [Linear Technology]
ホームページ  http://www.linear.com
Logo LINER - Linear Technology

LM134H データシート(HTML) 5 Page - Linear Technology

  LM134H Datasheet HTML 1Page - Linear Technology LM134H Datasheet HTML 2Page - Linear Technology LM134H Datasheet HTML 3Page - Linear Technology LM134H Datasheet HTML 4Page - Linear Technology LM134H Datasheet HTML 5Page - Linear Technology LM134H Datasheet HTML 6Page - Linear Technology LM134H Datasheet HTML 7Page - Linear Technology LM134H Datasheet HTML 8Page - Linear Technology LM134H Datasheet HTML 9Page - Linear Technology Next Button
Zoom Inzoom in Zoom Outzoom out
 5 / 12 page
background image
LM134 Series
5
APPLICATIO S I FOR ATIO
Basic Theory of Operation
The equivalent circuit of the LM134 is shown in Figure 1.
A reference voltage of 64mV is applied to the minus input
of A1 with respect to the Vpin. A1 serves the drive to Q2
to keep the R pin at 64mV, independent of the value of
RSET. Transistor Q1 is matched to Q2 at a 17:1 ratio so that
the current flowing out of the Vpin is always 1/18 of the
total current into the V+ pin. This total current is called ISET
and is equal to:
64
18
17
67 7
mV
R
mV
R
SET
SET




=
.
Figure 1.
The 67.7mV equivalent reference voltage is directly pro-
portional to absolute temperature in degrees Kelvin (see
curve, “Operating Current vs Temperature”). This means
that the reference voltage can be plotted as a straight line
going from 0mV at absolute zero temperature to 67.7mV
at 298
°K (25°C). The slope of this line is 67.7mV/298 =
227
µV/°C.
The accuracy of the device is specified as a percent error
at room temperature, or in the case of the -3 and -6
devices, as both a percent error and an equivalent tem-
perature error. The LM134 operating current changes at a
percent rate equal to (100)(227
µV/°C)/(67.7mV)=0.336%/
°C at 25°C, so each 1% operating current error is equiva-
lent to
≈3°C temperature error when the device is used as
a temperature sensor. The slope accuracy (temperature
coefficient) of the LM134 is expressed as a ratio com-
pared to unity. The LM134-3, for instance, is specified at
0.98 to 1.02, indicating that the maximum slope error of
+
+
RSET
ISET
64mV
A1
R
V
V+
Q2
Q1
134 F01
the device is
±2% when the room temperature current is
set to the exact desired value.
Supply Voltage Slew Rate
At slew rates above a given threshold (see curve), the
LM134 may exhibit nonlinear current shifts. The slewing
rate at which this occurs is directly proportional to ISET. At
ISET = 10µA, maximum dv/dt is 0.01V/µs; at ISET = 1mA,
the limits is 1V/
µs. Slew rates above the limit do not harm
the LM134, or cause large currents to flow.
Thermal Effects
Internal heating can have a significant effect on current
regulation for ISET greater than 100µA. For example, each
1V increase across the LM134 at ISET = 1mA will increase
junction temperature by
≈0.4°C in still air. Output current
(ISET) has a temperature coefficient of ≈0.33%/°C, so the
change in current due to temperature rise will be (0.4)(0.33)
= 0.132%. This is a 10:1 degradation in regulation com-
pared to true electrical effects. Thermal effects, therefore,
must be taken into account when DC regulation is critical
and ISET exceeds 100µA. Heat sinking of the TO-46 pack-
age or the TO-92 leads can reduce this effect by more than
3:1.
Shunt Capacitance
In certain applications, the 15pF shunt capacitance of the
LM134 may have to be reduced, either because of loading
problems or because it limits the AC output impedance of
the current source. This can be easily accomplished by
buffering the LM134 with a FET, as shown in the applica-
tions. This can reduce capacitance to less than 3pF and
improve regulation by at least an order of magnitude. DC
characteristics (with the exception of minimum input
voltage) are not affected.
Noise
Current noise generated by the LM134 is approximately 4
times the shot noise of a transistor. If the LM134 is used
as an active load for a transistor amplifier, input referred
noise will be increased by about 12dB. In many cases, this
is acceptable and a single stage amplifier can be built with
a voltage gain exceeding 2000.


同様の部品番号 - LM134H

メーカー部品番号データシート部品情報
logo
National Semiconductor ...
LM134H NSC-LM134H Datasheet
273Kb / 14P
   3-Terminal Adjustable Current Sources
LM134H NSC-LM134H Datasheet
755Kb / 14P
   3-Terminal Adjustable Current Sources
logo
Texas Instruments
LM134H TI-LM134H Datasheet
1Mb / 26P
[Old version datasheet]   LM134/LM234/LM334 3-Terminal Adjustable Current Sources
LM134H TI-LM134H Datasheet
1Mb / 26P
[Old version datasheet]   LM134/LM234/LM334 3-Terminal Adjustable Current Sources
LM134H TI1-LM134H Datasheet
1Mb / 25P
[Old version datasheet]   LM134/LM234/LM334 3-Terminal Adjustable Current Sources
More results

同様の説明 - LM134H

メーカー部品番号データシート部品情報
logo
Linear Technology
LM134 LINER-LM134_15 Datasheet
166Kb / 12P
   Constant Current Source and Temperature Sensor
LM334S8 LINER-LM334S8 Datasheet
110Kb / 2P
   Constant Current Source and Temperature Sensor
logo
NXP Semiconductors
PSSI2021SAY PHILIPS-PSSI2021SAY Datasheet
51Kb / 8P
   Constant current source
2001 May 07
logo
ON Semiconductor
AND8109 ONSEMI-AND8109 Datasheet
32Kb / 2P
   LED CONSTANT CURRENT SOURCE SCHEME
January, 2003 ??Rev. 0
logo
List of Unclassifed Man...
AN103 ETC1-AN103 Datasheet
53Kb / 5P
   The FET Constant-Current Source/Limiter
logo
Nexperia B.V. All right...
PSSI2021SAY NEXPERIA-PSSI2021SAY Datasheet
188Kb / 13P
   Constant current source in SOT353 package
Rev. 03 - 27 August 2009
logo
TEKTRONIX, INC.
6220 TEKTRONIX-6220 Datasheet
461Kb / 5P
   DC Current Source AC and DC Current Source
logo
BCD Semiconductor Manuf...
AP4313 BCDSEMI-AP4313_10 Datasheet
685Kb / 12P
   CONSTANT VOLTAGE AND CONSTANT CURRENT CONTROLLER
logo
Seaward Electronics Inc...
SE1052 SEAWARD-SE1052 Datasheet
288Kb / 8P
   Constant Voltage and Constant Current Controller
logo
Diodes Incorporated
AP4305 DIODES-AP4305 Datasheet
451Kb / 10P
   CONSTANT VOLTAGE AND CONSTANT CURRENT CONTROLLER
More results


Html Pages

1 2 3 4 5 6 7 8 9 10 11 12


データシート ダウンロード

Go To PDF Page


リンク URL




プライバシーポリシー
ALLDATASHEET.JP
ALLDATASHEETはお客様のビジネスに役立ちますか?  [ DONATE ] 

Alldatasheetは   |   広告   |   お問い合わせ   |   プライバシーポリシー   |   リンク交換   |   メーカーリスト
All Rights Reserved©Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn
Indian : Alldatasheet.in  |   Mexican : Alldatasheet.com.mx  |   British : Alldatasheet.co.uk  |   New Zealand : Alldatasheet.co.nz
Family Site : ic2ic.com  |   icmetro.com