LM13700MX/NOPB National Semiconductor, LM13700MX/NOPB Datasheet - Page 12

• Manufacturer Part Number: LM13700MX/NOPB
• Description: IC AMP DUAL OP TRANSCOND 16-SOIC
• Manufacturer: National Semiconductor

Specifications of LM13700MX/NOPB

• Amplifier Type: Transconductance
• Number Of Circuits: 2
• Output Type: Push-Pull
• Slew Rate: 50 V/µs
• Gain Bandwidth Product: 2MHz
• Current - Input Bias: 1µA
• Voltage - Input Offset: 300µV
• Current - Supply: 2.6mA
• Current - Output / Channel: 650µA
• Voltage - Supply, Single/dual (±): 10 V ~ 36 V, ±5 V ~ 18 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 16-SOIC (3.9mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• -3db Bandwidth: -
• Other names: *LM13700MX; *LM13700MX/NOPB; LM13700MX

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Voltage Controlled Resistors
Voltage Controlled Filters
OTA’s are extremely useful for implementing voltage con-
trolled filters, with the LM13700 having the advantage that
the required buffers are included on the I.C. The VC Lo-Pass
Filter of Figure 11 performs as a unity-gain buffer amplifier at
frequencies below cut-off, with the cut-off frequency being
the point at which X
(R/R
single RC roll-off (6 dB per octave) of the input signal ampli-
tude with a −3 dB point defined by the given equation, where
A
). At frequencies above cut-off the circuit provides a
C
/g
m
equals the closed-loop gain of
FIGURE 9. Voltage Controlled Resistor with Linearizing Diodes
FIGURE 8. Voltage Controlled Resistor, Single-Ended
(Continued)
12
g
shows a VC High-Pass Filter which operates in much the
same manner, providing a single RC roll-off below the de-
fined cut-off frequency.
Additional amplifiers may be used to implement higher order
filters as demonstrated by the two-pole Butterworth Lo-Pass
Filter of Figure 13 and the state variable filter of Figure 14.
Due to the excellent g
filters perform well over several decades of frequency.
m
is again 19.2 x I
ABC
m
tracking of the two amplifiers, these
at room temperature. Figure 12
00798115
00798116