OP293FSZ Analog Devices Inc, OP293FSZ Datasheet - Page 13

• Manufacturer Part Number: OP293FSZ
• Description: IC OPAMP GP 35KHZ DUAL 8SOIC
• Manufacturer: Analog Devices Inc
• Type: General Purpose Amplifierr

Specifications of OP293FSZ

• Slew Rate: 0.015 V/µs
• Design Resources: 4 mA-to-20 mA Loop-Powered Temperature Monitor Using ADuC7060/1 (CN0145)
• Amplifier Type: General Purpose
• Number Of Circuits: 2
• Output Type: Rail-to-Rail
• Gain Bandwidth Product: 35kHz
• Current - Input Bias: 20nA
• Voltage - Input Offset: 250µV
• Current - Supply: 30µA
• Current - Output / Channel: 25mA
• Voltage - Supply, Single/dual (±): 1.7 V ~ 36 V, ±0.85 V ~ 18 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• Op Amp Type: Precision
• No. Of Amplifiers: 2
• Bandwidth: 35kHz
• Supply Voltage Range: 2V To ± 18V
• Amplifier Case Style: SOIC
• No. Of Pins: 8
• Rail/rail I/o Type: No
• Number Of Elements: 2
• Unity Gain Bandwidth Product: 0.035MHz
• Common Mode Rejection Ratio: 96dB
• Input Offset Voltage: 250uV
• Input Bias Current: 20nA
• Single Supply Voltage (typ): 3/5/9/12/15/18/24/28V
• Voltage Gain In Db: 106.02dB
• Power Supply Rejection Ratio: 97dB
• Power Supply Requirement: Single/Dual
• Shut Down Feature: No
• Single Supply Voltage (min): 2V
• Single Supply Voltage (max): 36V
• Dual Supply Voltage (min): ±1V
• Dual Supply Voltage (max): ±18V
• Operating Temp Range: -40C to 125C
• Operating Temperature Classification: Automotive
• Mounting: Surface Mount
• Pin Count: 8
• Package Type: SOIC N
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• -3db Bandwidth: -
• Lead Free Status / Rohs Status: Compliant

FUNCTIONAL DESCRIPTION
The OP193/OP293 operational amplifiers are single-supply,
micropower, precision amplifiers whose input and output ranges
both include ground. Input offset voltage (V
maximum, while the output delivers ±5 mA to a load. Supply
current is only 15 μA.
A simplified schematic of the input stage is shown in Figure 26.
The input transistors, Q1 and Q2, are PNP devices, which permit
the inputs to operate down to ground potential. The input transis-
tors have resistors in series with the base terminals to protect
the junctions from overvoltage conditions. The second stage is
an NPN cascode that is buffered by an emitter follower before
driving the final PNP gain stage.
The OP193 includes connections to taps on the input load resis-
tors, which can be used to null the input offset voltage, V
The OP293 have two additional transistors, Q7 and Q8. The
behavior of these transistors is discussed in the Output Phase
Reversal—OP193 and Output Phase Reversal—OP293 sections.
The output stage, shown in Figure 25, is a noninverting NPN
totem-pole configuration. Current is sourced to the load by
Emitter Follower Q1, while Q2 provides current sink capability.
When Q2 saturates, the output is pulled to within 5 mV of
ground without an external pull-down resistor. The totem-pole
output stage supplies a minimum of 5 mA to an external load,
even when operating from a single 3.0 V power supply.
+INPUT
–INPUT
OP293
ONLY
2kΩ
2kΩ
OS
) is only 100 μV
Q7
Figure 26. OP193/OP293 Equivalent Input Circuit
R1
R1
(OP193 ONLY)
A
B
TERMINALS
Q1
NULLING
OS
.
I1
Q2
Rev. C | Page 13 of 20
R2
R2
A
B
Q8
Q3
I2
By operating as an emitter follower, Q1 offers a high impedance
load to the final PNP collector of the input stage. Base drive to
Q2 is derived by monitoring Q1’s collector current. Transistor
Q5 tracks the collector current of Q1. When Q1 is on, Q5 keeps
Q4 off, and Current Source I1 keeps Q2 turned off. When Q1 is
driven to cutoff (that is, the output must move toward V−), Q5
allows Q4 to turn on. Q4’s collector current then provides the
base drive for Q3 and Q2, and the output low voltage swing is
set by Q2’s V
DRIVING CAPACITIVE LOADS
The OP193/OP293 amplifiers are unconditionally stable with
capacitive loads less than 200 pF. However, the small signal,
unity-gain overshoot improves if a resistive load is added. For
example, transient overshoot is 20% when driving a 1000 pF,
10 kΩ load. When driving large capacitive loads in unity-gain
configurations, an in-the-loop compensation technique is
recommended, as illustrated in Figure 30.
Q4
I3
STAGE
INPUT
FROM
I4
Figure 25. OP193/OP293 Equivalent Output Circuit
D1
CE,SAT
Q5
I5
, which is about 5 mV.
Q6
TO
OUTPUT
STAGE
I6
I3
V+
V–
Q4
I2
Q3
Q1
I1
Q2
OP193/OP293
Q5
V+
V–
OUTPUT