Os motores de busca de Datasheet de Componentes eletrônicos
  Portuguese  ▼
ALLDATASHEETPT.COM

X  

ADR520ART-REEL7 Folha de dados(PDF) 11 Page - Analog Devices

Nome de Peças ADR520ART-REEL7
Descrição Electrónicos  High Precision Shunt Mode Voltage References
Download  16 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Fabricante Electrônico  AD [Analog Devices]
Página de início  http://www.analog.com
Logo AD - Analog Devices

ADR520ART-REEL7 Folha de dados(HTML) 11 Page - Analog Devices

Back Button ADR520ART-REEL7 Datasheet HTML 7Page - Analog Devices ADR520ART-REEL7 Datasheet HTML 8Page - Analog Devices ADR520ART-REEL7 Datasheet HTML 9Page - Analog Devices ADR520ART-REEL7 Datasheet HTML 10Page - Analog Devices ADR520ART-REEL7 Datasheet HTML 11Page - Analog Devices ADR520ART-REEL7 Datasheet HTML 12Page - Analog Devices ADR520ART-REEL7 Datasheet HTML 13Page - Analog Devices ADR520ART-REEL7 Datasheet HTML 14Page - Analog Devices ADR520ART-REEL7 Datasheet HTML 15Page - Analog Devices Next Button
Zoom Inzoom in Zoom Outzoom out
 11 / 16 page
background image
ADR520/ADR525/ADR530/ADR540/ADR550
Rev. E | Page 11 of 1
6
THEORY OF OPERATION
The ADR520/ADR525/ADR530/ADR540/ADR550 use the
band gap concept to produce a stable, low temperature coefficient
voltage reference suitable for high accuracy data acquisition
components and systems. The devices use the physical nature of a
silicon transistor base-emitter voltage (VBE) in the forward-biased
operating region. All such transistors have approximately a
−2 mV/°C temperature coefficient (TC), making them unsuitable
for direct use as low temperature coefficient references. Extra-
polation of the temperature characteristics of any one of these
devices to absolute zero (with the collector current proportional
to the absolute temperature), however, reveals that its VBE
approaches approximately the silicon band gap voltage. Thus,
if a voltage develops with an opposing temperature coefficient
to sum the VBE, a zero temperature coefficient reference results.
The ADR520/ADR525/ADR530/ADR540/ADR550 circuit
shown in Figure 18 provides such a compensating voltage (V1)
by driving two transistors at different current densities and
amplifying the resultant VBE difference (ΔVBE, which has a
positive temperature coefficient). The sum of VBE and V1
provides a stable voltage reference over temperature.
VBE
+
ΔVBE
+
V1
V–
V+
+
Figure 18. Circuit Schematic
APPLICATIONS
The ADR520/ADR525/ADR530/ADR540/ADR550 are a
series of precision shunt voltage references. They are designed
to operate without an external capacitor between the positive
and negative terminals. If a bypass capacitor is used to filter the
supply, the references remain stable.
All shunt voltage references require an external bias resistor (RBIAS)
between the supply voltage and the reference (see Figure 19).
RBIAS sets the current that flows through the load (IL) and the
reference (IIN). Because the load and the supply voltage can vary,
RBIAS needs to be chosen based on the following considerations:
RBIAS must be small enough to supply the minimum IIN
current to the ADR520/ADR525/ADR530/ADR540/
ADR550, even when the supply voltage is at its minimum
value and the load current is at its maximum value.
RBIAS must be large enough so that IIN does not exceed
15 mA when the supply voltage is at its maximum value
and the load current is at its minimum value.
VOUT
VS
ADR550
IL
IIN
R
IIN + IL
Figure 19. Shunt Reference
Given these conditions, RBIAS is determined by the supply
voltage (VS), the load and operating currents (IL and IIN) of
the ADR520/ADR525/ADR530/ADR540/ADR550, and the
output voltage (VOUT) of the ADR520/ADR525/ADR530/
ADR540/ADR550.
IN
L
OUT
S
BIAS
I
I
V
V
R
+
=
(3)
Precision Negative Voltage Reference
The ADR520/ADR525/ADR530/ADR540/ADR550 are suit-
able for applications where a precise negative voltage is desired.
Figure 20 shows the ADR525 configured to provide a negative
output.
VS
–2.5V
ADR525
R
Figure 20. Negative Precision Reference Configuration
Output Voltage Trim
The trim terminal of the ADR520/ADR525/ADR530/ADR540/
ADR550 can be used to adjust the output voltage over a range
of ±0.5%. This allows systems designers to trim system errors
by setting the reference to a voltage other than the preset output
voltage. An external mechanical or electrical potentiometer can
be used for this adjustment. Figure 21 illustrates how the output
voltage can be trimmed using the AD5273, an Analog Devices,
Inc., 10 kΩ potentiometer.
R1
470kΩ
POTENTIOMETER
10kΩ
ADR530
AD5273
R
VOUT
VS
Figure 21. Output Voltage Trim


Nº de peça semelhante - ADR520ART-REEL7

Fabricante ElectrônicoNome de PeçasFolha de dadosDescrição Electrónicos
logo
Analog Devices
ADR520ART-REEL7 AD-ADR520ART-REEL7 Datasheet
210Kb / 16P
   High Precision Shunt Mode Voltage References
REV. A
More results

Descrição semelhante - ADR520ART-REEL7

Fabricante ElectrônicoNome de PeçasFolha de dadosDescrição Electrónicos
logo
Analog Devices
ADR530 AD-ADR530_15 Datasheet
413Kb / 16P
   High Precision Shunt Mode Voltage References
Rev. E
ADR525 AD-ADR525_15 Datasheet
413Kb / 16P
   High Precision Shunt Mode Voltage References
Rev. E
ADR530BRTZ-REEL7 AD-ADR530BRTZ-REEL7 Datasheet
413Kb / 16P
   High Precision Shunt Mode Voltage References
Rev. E
ADR520 AD-ADR520 Datasheet
210Kb / 16P
   High Precision Shunt Mode Voltage References
REV. A
ADR520 AD-ADR520_15 Datasheet
413Kb / 16P
   High Precision Shunt Mode Voltage References
Rev. E
ADR540 AD-ADR540_15 Datasheet
413Kb / 16P
   High Precision Shunt Mode Voltage References
Rev. E
ADR550 AD-ADR550_15 Datasheet
413Kb / 16P
   High Precision Shunt Mode Voltage References
Rev. E
ADR530ART AD-ADR530ART Datasheet
273Kb / 12P
   High Precision Shunt Mode Voltage References
Rev. F
ADR5043 AD-ADR5043_15 Datasheet
425Kb / 16P
   Precision Micropower Shunt Mode Voltage References
REV. B
ADR5045 AD-ADR5045_15 Datasheet
425Kb / 16P
   Precision Micropower Shunt Mode Voltage References
REV. B
More results


Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16


Folha de dados Download

Go To PDF Page


Ligação URL




Privacy Policy
ALLDATASHEETPT.COM
ALLDATASHEET é útil para você?  [ DONATE ] 

Sobre Alldatasheet   |   Publicidade   |   Contato conosco   |   Privacy Policy   |   roca de Link   |   Lista de Fabricantes
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