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OPA353NA Datasheet, PDF (8/26 Pages) Texas Instruments – High-Speed, Single-Supply, Rail-to-Rail PERATIONAL AMPLIFIERS | |||
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APPLICATIONS INFORMATION
OPA353 series op amps are fabricated on a state-of-the-art
0.6 micron CMOS process. They are unity-gain stable and
suitable for a wide range of general purpose applications.
Rail-to-rail input/output make them ideal for driving sam-
pling A/D converters. They are well suited for controlling
the output power in cell phones. These applications often
require high speed and low noise. In addition, the OPA353
series offers a low cost solution for general purpose and
consumer video applications (75⦠drive capability).
Excellent ac performance makes the OPA353 series well
suited for audio applications. Their bandwidth, slew rate,
low noise (5nV/âHz), low THD (0.0006%), and small pack-
age options are ideal for these applications. The class AB
output stage is capable of driving 600⦠loads connected to
any point between V+ and ground.
Rail-to-rail input and output swing significantly increases
dynamic range, especially in low voltage supply applica-
tions. Figure 1 shows the input and output waveforms for
VS = +5, G = +1, RL = 1kâ¦
5V
VIN
0
5V
VOUT
0
FIGURE 1. Rail-to-Rail Input and Output.
the OPA353 in unity-gain configuration. Operation is
from a single +5V supply with a 1k⦠load connected to
VS/2. The input is a 5Vp-p sinusoid. Output voltage is
approximately 4.95Vp-p.
Power supply pins should be bypassed with 0.01µF ceramic
capacitors.
OPERATING VOLTAGE
OPA353 series op amps are fully specified from +2.7V to
+5.5V. However, supply voltage may range from +2.5V to
+5.5V. Parameters are guaranteed over the specified supply
rangeâa unique feature of the OPA353 series. In addition,
many specifications apply from â40°C to +85°C. Most
behavior remains virtually unchanged throughout the full
operating voltage range. Parameters which vary signifi-
cantly with operating voltages or temperature are shown in
the typical performance curves.
RAIL-TO-RAIL INPUT
The guaranteed input common-mode voltage range of the
OPA353 series extends 100mV beyond the supply rails. This
is achieved with a complementary input stageâan
N-channel input differential pair in parallel with a P-channel
differential pair (see Figure 2). The N-channel pair is active
for input voltages close to the positive rail, typically
(V+) â 1.8V to 100mV above the positive supply, while the
P-channel pair is on for inputs from 100mV below the
negative supply to approximately (V+) â 1.8V. There is a
small transition region, typically (V+) â 2V to (V+) â 1.6V, in
which both pairs are on. This 400mV transition region can
vary ±400mV with process variation. Thus, the transition
region (both input stages on) can range from (V+) â 2.4V to
(V+) â 2.0V on the low end, up to (V+) â 1.6V to (V+) â 1.2V
on the high end.
V+
Reference
Current
VIN+
VINâ
VBIAS1
Class AB
Control
VO
Circuitry
VBIAS2
Vâ
(Ground)
FIGURE 2. Simplified Schematic.
®
OPA353, 2353, 4353
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