BETAIndependent OTAs2 plus two separate buffers
Dual operational transconductance amplifier
LM13700 Specifications
Review LM13700 electrical specifications, operating conditions and package details.
Package view
Key specifications
The OTA controls output current. A load resistor supplies the current-to-voltage conversion; the optional buffer is a separate stage.
Recommended total rail span9.5–32 V
Typical transconductance9.6 mS at IABC = 500 µA
Operating grade0–70 °C
Package details
LM13700N · PDIP-16
| Property | Details |
|---|---|
| Manufacturer | Texas Instruments |
| Part number | LM13700N |
| Package | PDIP-16 |
| Connections | 16 pins |
| Mounting | Through-hole |
| Lead pitch | 2.54 mm |
| Package code | PDIP-16 |
| Thermal reference | See operating and package limits |
Supplies and limits
Recommended conditions and absolute ratings
Manufacturer specifications 7 parameters
Scroll sideways to see all columns.
| Parameter | Value | Conditions / notes |
|---|---|---|
| Recommended total supply | 9.5–32 V | Single-supply configuration |
| Recommended split supplies | ±4.75 to ±16 V | Symmetric dual-supply configuration |
| Example supply | +15 V / GND / −15 V | 30 V total rail span |
| Operating temperature | 0 to +70°C | Commercial grade |
| Absolute supply limit | 36 V total / ±18 V | Stress limit, not the operating target |
| Absolute IABC / diode current | 2 mA each | External current limiting is required |
| Absolute buffer output current | 20 mA | Also constrained by package dissipation |
No specifications match. Try a parameter name or a unit.
Circuit GND is the midpoint of the split supply; it is not the V− pin.
OTA characteristics
±15 V, 25°C, IABC = 500 µA unless noted
Manufacturer specifications 8 parameters
Scroll sideways to see all columns.
| Parameter | Value | Conditions / notes |
|---|---|---|
| Forward transconductance | 6.7–13 mS; 9.6 mS typical | 5.4 mS minimum over specified temperature |
| Channel gm tracking | 0.3 dB typical | Manufacturer reference conditions |
| Input offset | 0.4 mV typical; 4 mV maximum | Manufacturer specified-temperature condition |
| Input bias current | 0.4 µA typical; 5 µA maximum | 1 µA typical / 8 µA maximum over temperature |
| Input resistance | 26 kΩ typical; 10 kΩ minimum | Reference test conditions |
| Common-mode input range | ±12 V minimum; ±13.5 V typical | With ±15 V rails |
| Peak output current | 500 µA typical; 350–650 µA | IABC = 500 µA, RL = 0 |
| Supply current | 2.6 mA typical | Both channels, IABC = 500 µA |
No specifications match. Try a parameter name or a unit.
Typical transconductance and example gain are not guaranteed exact values.
Signal behavior
OTA and buffer are different stages
Manufacturer specifications 7 parameters
Scroll sideways to see all columns.
| Parameter | Value | Conditions / notes |
|---|---|---|
| Small-signal equation | IOUT ≈ gm × (VIN+ − VIN−) | Without the linearizing diodes, use a few millivolts differential |
| Typical gm at 25°C | Approximately 19.2 × IABC | IABC in amperes gives gm in siemens |
| Current-to-voltage conversion | VOUT ≈ IOUT × RL | Valid while output swing and current remain in range |
| Open-loop bandwidth | 2 MHz typical | Not a guaranteed closed-loop bandwidth for every circuit |
| Slew rate | 50 V/µs typical | Unity-gain compensated test |
| Separate buffers | Darlington emitter followers | Input must be connected externally; output has a level shift |
| Buffer load | Bias toward V− when used | Manufacturer buffer test uses 5 kΩ to V− |
No specifications match. Try a parameter name or a unit.
The LM13700 is not a pin-compatible replacement for a conventional dual voltage op amp.
Small-signal gain experiment
One OTA with an unbuffered resistive output
Manufacturer specifications 8 parameters
Scroll sideways to see all columns.
| Parameter | Value | Conditions / notes |
|---|---|---|
| V+11 / V−6 | +15 V / −15 V | 100 nF bypass from each rail to GND |
| IABC A1 | 150 kΩ to GND | Approximately 90.7 µA at the assumed bias voltage |
| IN+ A3 / IN− A4 | ±2 mV sine / GND | 1 kHz, zero DC offset |
| OUT A5 | 10 kΩ to GND plus high-impedance scope | Scope input capacitance affects high-frequency response |
| DIODE A2 and B15 | Open | Linearizing diodes unused in this experiment |
| BUF IN A7 and B10 | GND | BUF OUT A8 and B9 left open |
| Unused channel B | IN−13 and IN+14 to GND | IABC B16 and OUT B12 open |
| All source returns | Circuit GND | The split-supply midpoint, not −15 V |
No specifications match. Try a parameter name or a unit.
This is an explanatory circuit, not a running simulation. Offset and bias currents may add a DC output offset.
Gain calculation
Nominal 25°C example
Manufacturer specifications 7 parameters
Scroll sideways to see all columns.
| Parameter | Value | Conditions / notes |
|---|---|---|
| Bias pin estimate | V− + 2 VBE ≈ −13.6 V | Assume VBE ≈ 0.7 V |
| Bias current | 13.6 V / 150 kΩ ≈ 90.7 µA | Resistor goes from GND to IABC A1 |
| Transconductance | 19.2 × 90.7 µA ≈ 1.74 mS | Typical small-signal approximation |
| Voltage gain | 1.74 mS × 10 kΩ ≈ 17.4 V/V | About 24.8 dB |
| Signal output | 2 mV peak × 17.4 ≈ 34.8 mV peak | Excludes DC offset and tolerances |
| Use 300 kΩ instead | Approximately 8.7 V/V | Lower bias reduces gain |
| Use 100 kΩ instead | Approximately 26.1 V/V | Higher bias increases gain |
No specifications match. Try a parameter name or a unit.
Changing temperature, resistor tolerance, junction voltage or the actual gm changes these results.
Using the linearizing diodes
Advanced input conditioning
Manufacturer specifications 6 parameters
Scroll sideways to see all columns.
| Parameter | Value | Conditions / notes |
|---|---|---|
| Purpose | Reduce transfer nonlinearity | The diodes must be biased with current |
| Diode current requirement | ID greater than twice input signal current | Use the manufacturer circuit and input attenuation |
| Manufacturer VCA example | About 1 mA diode bias | 13 kΩ from +15 V, approximate 0.7 V diode node |
| Input amplitude | Attenuate before the OTA | A large differential voltage clips or distorts without suitable conditioning |
| Control-voltage conversion | Resistor feeds IABC from a control voltage | Include the V− + 2 VBE bias-pin offset |
| Buffer wiring | OUT5 to BUF IN7 only when intended | This connection is external, not inside the IC |
No specifications match. Try a parameter name or a unit.
The simple illustrated circuit deliberately leaves the diodes and buffers unused to isolate the gm principle.
Packages and ordering
LM13700N · PDIP-16
Manufacturer specifications 5 parameters
Scroll sideways to see all columns.
| Parameter | Value | Conditions / notes |
|---|---|---|
| SOIC-16 | LM13700M/NOPB; LM13700MX/NOPB | Listed in TI ordering appendix dated 10 November 2025 |
| PDIP-16 | LM13700N | Historical package documented in the datasheet; not listed in that current appendix |
| Pin map | Same 16 physical functions | Top view, pin 1 at the notch end |
| Body / pitch | PDIP: 19.304 × 6.35 mm / 2.54 mm | SOIC: 9.90 × 3.91 mm / 1.27 mm |
| Footprint provenance | Original TEP editable land patterns | Verify the exact mechanical drawing and assembly process |
No specifications match. Try a parameter name or a unit.
Legacy package visualization is not a claim of current availability.
Connections by function
Select a pin for its function, connection guidance and electrical notes.