XR1009 Datasheet, PDF (9/16 Pages) Exar Corporation – 0.2mA, 35MHz Rail-to-Rail Amplifiers

Application Information
General Description
The XR1009 and XR2009 are a single supply, general
purpose, voltage-feedback ampli ers fabricated on a
complementary bipolar process. The XR1009 offers 35MHz
unity gain bandwidth, 27V/μs slew rate, and only 208μA
supply current. It features a rail-to-rail output stage and is
unity gain stable.
The design utilizes a patent pending topology that provides
increased slew rate performance. The common mode input
range extends to 300mV below ground and to 1.2V below
Vs. Exceeding these values will not cause phase reversal.
However, if the input voltage exceeds the rails by more than
0.5V, the input ESD devices will begin to conduct. The output
will stay at the rail during this overdrive condition.
The design uses a Darlington output stage. The output
stage is short circuit protected and offers “soft” saturation
protection that improves recovery time.
Figures 1, 2, and 3 illustrate typical circuit con gurations for
non-inverting, inverting, and unity gain topologies for dual
supply applications. They show the recommended bypass
capacitor values and overall closed loop gain equations.
Figure 4 shows the typical non-inverting gain circuit for
single supply applications.
+Vs
6.8μF
Input
+
0.1μF
-
0.1μF
Rf
Output
RL
Rg
6.8μF
-Vs
G = 1 + (Rf/Rg)
Figure 1: Typical Non-Inverting Gain Circuit
XR1009, XR2009
+Vs
6.8μF
Input
R1
+
Rg
-
0.1μF
0.1μF
Rf
Output
RL
6.8μF
-Vs
G = - (Rf/Rg)
For optimum input offset
voltage set R1 = Rf || Rg
Figure 2: Typical Inverting Gain Circuit
+Vs
6.8μF
Input
+
0.1μF
-
0.1μF
Output
RL
6.8μF
-Vs
G=1
Figure 3: Unity Gain Circuit
+V_s
6.8μF
+
In
0.1μF
+
Out
-
R_f
R_g
Figure 4: Single Supply Non-Inverting Gain Circuit
© 2014 Exar Corporation
9 / 16
exar.com/XR1009
Rev 1B