OP482GPZ Analog Devices Inc, OP482GPZ Datasheet - Page 13

• Manufacturer Part Number: OP482GPZ
• Description: IC OPAMP JFET 4MHZ QUAD LP 14DIP
• Manufacturer: Analog Devices Inc

Specifications of OP482GPZ

• Slew Rate: 9 V/µs
• Amplifier Type: General Purpose
• Number Of Circuits: 4
• Gain Bandwidth Product: 4MHz
• Current - Input Bias: 3pA
• Voltage - Input Offset: 200µV
• Current - Supply: 210µA
• Current - Output / Channel: 12mA
• Voltage - Supply, Single/dual (±): 9 V ~ 36 V, ±4.5 V ~ 18 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Through Hole
• Package / Case: 14-DIP (0.300", 7.62mm)
• Op Amp Type: Low Power
• No. Of Amplifiers: 4
• Bandwidth: 4MHz
• Supply Voltage Range: ± 4.5V To ± 18V
• Amplifier Case Style: DIP
• No. Of Pins: 14
• Operating Temperature Range: -40°C To +85°C
• Common Mode Rejection Ratio: 90
• Current, Input Bias: 3 pA
• Current, Input Offset: 1 pA
• Current, Output: 10 mA
• Current, Supply: 210 μA
• Impedance, Thermal: 39 °C/W
• Number Of Amplifiers: Quad
• Package Type: PDIP-14
• Temperature, Operating, Range: -40 to +85 °C
• Voltage, Gain: 20 V/mV
• Voltage, Input: -11 to +15 V
• Voltage, Noise: 36 nV/sqrt Hz
• Voltage, Offset: 0.2 mV
• Voltage, Output, High: 13.9 V
• Voltage, Output, Low: -13.9 V
• Voltage, Supply: ±15 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Output Type: -
• -3db Bandwidth: -
• Lead Free Status / Rohs Status: RoHS Compliant part Electrostatic Device

PROGRAMMABLE STATE-VARIABLE FILTER
The circuit shown in Figure 46 can be used to accurately
program the Q, the cutoff frequency f
state variable filter. OP482s have been used in this design
because of their high bandwidths, low power, and low noise.
This circuit takes only three packages to build because of the
quad configuration of the op amps and DACs.
The DACs shown are used in the voltage mode; therefore, many
values are dependent on the accuracy of the DAC only and not
on the absolute values of the DAC’s resistive ladders. This makes
this circuit unusually accurate for a programmable filter.
Adjusting DAC 1 changes the signal amplitude across R1;
therefore, the DAC attenuation times R1 determines the amount
of signal current that charges the integrating capacitor, C1. This
cutoff frequency can now be expressed as
V
IN
DAC8408
1/4
OP482
1/4
2kΩ
2kΩ
R5
R6
OP482
C
1/4
2kΩ
, and gain of a 2-pole
R4
HIGH PASS
OP482
2kΩ
R3
DAC8408
1/4
1/4
2kΩ
R2
Rev. F | Page 13 of 16
OP482
1/4
OP482
Figure 46.
1/4
2kΩ
R1
where D1 is the digital code for the DAC.
The gain of this circuit is set by adjusting D3 . The gain equation is
DAC 2 is used to set the Q of the circuit. Adjusting this DAC
controls the amount of feedback from the band-pass node to
the input summing node. Note that the digital value of the
DAC is in the numerator; therefore, zero code is not a valid
operating point.
DAC8408
OP482
Gain
Q
1/4
fc
1000pF
1/4
=
=
C1
R2
R3
2π
=
R1C1
R4
R5
⎛
⎜
⎝
1
256
D2
2kΩ
R7
⎛
⎜
⎝
DAC8408
256
D3
⎞
⎟
⎠
⎛
⎜
⎝
1/4
256
D1
BAND PASS
⎞
⎟
⎠
⎞
⎟
⎠
OP482
1/4
2kΩ
R1
OP282/OP482
OP482
1000pF
1/4
C1
PASS
LOW