AD8610ARM Analog Devices, AD8610ARM Datasheet - Page 9

• Manufacturer Part Number: AD8610ARM
• Description: Precision Very Low Noise Low Input Bias Current Wide Bandwith JFET Operational Amplifier
• Manufacturer: Analog Devices

FUNCTIONAL DESCRIPTION
The AD8610 is manufactured on Analog Devices’ proprietary
XFCB (eXtra Fast Complementary Bipolar) process. XFCB is
fully dielectrically isolated (DI) and used in conjunction with
N-channel JFET technology and trimmable thin-film resistors to
create the world’s most precise JFET input amplifier. Dielectrically
isolated NPN and PNP transistors fabricated on XFCB have F
greater than 3 GHz. Low T
offset voltage and offset voltage tempco trimming. These process
breakthroughs allowed Analog Devices’ world class IC designers
to create an amplifier with faster slew rate and more than 50%
higher bandwidth at half of the current consumed by its closest
competition. The AD8610 is unconditionally stable in all gains,
even with capacitive loads well in excess of 1 nF. The AD8610B
achieves less than 100 µV of offset and 1 µV/°C of offset drift,
numbers usually associated with very high precision bipolar input
amplifiers. The AD8610 is offered in the tiny 8-lead MSOP as well
as narrow 8-lead SOIC surface-mount packages and is fully specified
with supply voltages from ±5 V to ±13 V. The very wide specified
temperature range, up to 125°C, guarantees superior operation in
systems with little or no active cooling.
The unique input architecture of the AD8610 features extremely
low input bias currents and very low input offset voltage. Low
power consumption minimizes the die temperature and maintains
the very low input bias current. Unlike many competitive JFET
amplifiers, the AD8610 input bias currents are low even at elevated
temperatures. Typical bias currents are less than 200 pA at 85°C.
The gate current of a JFET doubles every 10°C resulting in a similar
increase in input bias current over temperature. Special care should
C
TIME – 400ns/DIV
thin-film resistors enable very accurate
V
V
A
R
SR = 55V/ s
C
IN
S
V
L
L
=
= 2k
= 20pF
=
p-p = 20V
13V
1
T
be given to the PC board layout to minimize leakage currents
between PCB traces. Improper layout and board handling gener-
ates leakage current that exceeds the bias current of the AD8610.
Power Consumption
A major advantage of the AD8610 in new designs is the saving of
power. Lower power consumption of the AD8610 makes it much
more attractive for portable instrumentation and for high-density
systems, simplifying thermal management, and reducing power
supply performance requirements. Compare the power consumption
of the AD8610 versus the OPA627 in Figure 1.
8
7
6
5
4
3
2
–75
–50
–25
OPA627
TEMPERATURE – C
TIME – 400ns/DIV
0
AD8610
25
50
SR = 50V/ s
V
V
A
R
C
S
IN
V
L
L
=
=
= 2k
= 20pF
p-p = 20V
13V
1
75
AD8610
100
125