Low Power, Precision Reference
and Op Amp
ADR821/ADR827
FUNCTIONAL BLOCK DIAGRAM
FEATURES
10-lead MSOP
ADR821/ADR827
1
2
3
4
5
10
9
V+
AMP_OUT
400 μA supply current
−40°C to +125°C temperature range
On-board precision resistors
Reference
ADR821: 2.8 V to 15 V operation
ADR827: 2.7 V to 15 V operation
0.2ꢀ initial accuracy
15 ppm/°C temperature drift maximum
+5 mA/−3 mA output drive
Amplifier
R
R
2
1
R
1
R
2
–IN
GND
8
7
+IN
NC
V–
REF
6
REF_OUT
NC = NO CONNECT
Figure 1.
ADR821
2.8 V to 15 V operation
2.8 V to 15 V single-supply operation
ADR827
2.7 V to 15 V operation
2.7 V to 15 V single-supply operation
Rail-to-rail input and output
500 μV offset voltage maximum
50 nA bias current maximum
Unity gain stable
Table 1. Selection Table
Reference Reference
Reference
Temperature
Coefficient
Part No.
VOUT
Accuracy
ADR827ARMZ 1.25 V
ADR827BRMZ 1.25 V
ADR821ARMZ 2.5± V
ADR821BRMZ 2.5± V
±±.ꢀ4
±±.24
±±.ꢀ4
±±.24
3± ppm/°C
15 ppm/°C
3± ppm/°C
15 ppm/°C
No phase reversal
APPLICATIONS
Battery-powered instrumentation
Portable medical instrumentation
Data acquisition systems
Industrial process controls
Automotive applications
GENERAL DESCRIPTION
The ADR821/ADR827 combines a precision voltage reference
and an op amp in a 10-lead mini small outline package (MSOP).
The reference and the op amp can be operated independently,
offering the user a range of flexibility when arranging the
combination. Featuring a combined operating current of less
than 400 μA and 15 ppm/°C temperature drift on the reference,
the ADR821/ADR827 are ideally suited for applications requir-
ing precision and low power.
Available with the reference at 1.25 V and at 2.5 V, the
ADR821/ADR827 also come in two grades. The reference on
the A grade offers 30 ppm/°C temperature drift performance
and 0.4% initial accuracy. The B grade provides a tighter
temperature drift performance of 15 ppm/°C and only 0.2%
initial accuracy. All versions operate from −40°C to +125°C.
Rev. 0
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