MAX492ESA-T Maxim Integrated, MAX492ESA-T Datasheet - Page 12

• Manufacturer Part Number: MAX492ESA-T
• Description: Operational Amplifiers - Op Amps Dual uPower Single Supply Rail-Rail
• Manufacturer: Maxim Integrated

Specifications of MAX492ESA-T

• Number Of Channels: 2
• Common Mode Rejection Ratio (min): 74 dB
• Input Offset Voltage: 500 uV
• Input Bias Current (max): 60 nA
• Operating Supply Voltage: 2.7 V to 6 V, +/- 1.35 V to +/- 3 V
• Mounting Style: SMD/SMT
• Package / Case: SOIC-8 Narrow
• Slew Rate: 0.2 V/us
• Shutdown: No
• Output Current: 30 mA
• Maximum Operating Temperature: + 85 C
• Amplifier Type: Micropower Amplifier
• Gain Bandwidth Product: 0.5 MHz
• Maximum Dual Supply Voltage: +/- 3 V
• Minimum Dual Supply Voltage: +/- 1.35 V
• Minimum Operating Temperature: - 40 C
• Supply Current: 150 uA
• Voltage Gain Db: 110 dB

the op amp in an inverting configuration (Figure 3a);
connect resistor R3 between the noninverting input and
the input signal when using the op amp in a noninvert-
ing configuration (Figure 3b). Select R3 to equal the
parallel combination of R1 and R2. High source resis-
tances will degrade noise performance, due to the ther-
mal noise of the resistor and the input current noise
(which is multiplied by the source resistance).
T
tion circuitry that prevents damage to the precision
input stage from large differential input voltages. This
protection circuitry consists of back-to-back diodes
between IN+ and IN- with two 1.7k
Figure 3a. Reducing Offset Error Due to Bias Current:
Inverting Configuration
Figure 3b. Reducing Offset Error Due to Bias Current:
Noninverting Configuration
he MAX492/MAX494/MAX495 include internal protec-
V
IN
R3 = R2
V
IN
II
R1
Input Stage Protection Circuitry
R1
R3
______________________________________________________________________________________
R3
MAX49_
MAX49_
R2
R3 = R2
Single-Supply Rail-to-Rail Op Amps
II
R1
resistors in series
R2
R1
V
V
Single/Dual/Quad, Micropower,
OUT
OUT
(Figure 4). The diodes limit the differential voltage
applied to the amplifiers’ internal circuitry to no more
than V
(about 0.7V at +25°C).
Input bias current for the ICs (±25nA typical) is speci-
fied for the small differential input voltages. For large
differential input voltages (exceeding V
tion circuitry increases the input current at IN+ and IN-:
For comparator applications requiring large differential
voltages (greater than V
rent that flows through the diodes with external resistors
Figure 4. Input Stage Protection Circuitry
Figure 5. Capacitive-Load Stable Region Sourcing Current
IN+
IN–
Input Current = ———————————
F
10,000
, where V
1000
100
1
1.7k
1.7k
F
is the diodes’ forward-voltage drop
RESISTIVE LOAD (k )
UNSTABLE REGION
(V
F
), you can limit the input cur-
IN
10
+ - V
2 x 1.7k
TO INTERNAL
CIRCUITRY
TO INTERNAL
CIRCUITRY
IN
V
V
R
A
CC
OUT
V
- ) - V
L
TO V
= +1
= +5V
= V
EE
CC
F
F
/2
), this protec-
100
MAX492
MAX494
MAX495
11