Texas Instruments LM13700M/NOPB

Overview

LM13700M/NOPB from Texas Instruments is a dual operational transconductance amplifier (OTA) with linearizing diodes and high-impedance output buffers, designed for voltage-controlled analog signal processing. It delivers 6-decade gm adjustability (5 μA–500 μA), <0.5 mV input offset voltage, and >100 dB crosstalk isolation between channels - enabling precise stereo audio amplification, VCOs, and current-controlled filters in ±15 V systems.

For engineers reviewing the LM13700M/NOPB datasheet, LM13700M/NOPB pinout, LM13700M/NOPB application, or LM13700M/NOPB equivalent, key selection criteria include gm linearity over bias current, buffer output drive capability (±14.2 V swing), diode-bias-dependent distortion performance (<0.1% THD with linearizing diodes), and thermal derating requirements for SOIC-16 packaging.

Technical Context

The LM13700M/NOPB implements two independent current-controlled transconductance stages, each with differential NPN input pairs biased by dedicated IABC pins (pins 1/16) and linearizing diodes (pins 2/15) to extend input dynamic range. Its transconductance (gm ≈ 19.2 × IABC at 25°C) is directly proportional to amplifier bias current, enabling precise gain control without feedback resistors.

Each channel integrates a Darlington-buffered output stage capable of ±20 mA continuous drive and sustained short-to-ground operation, with buffer input bias currents independent of IABC - a key functional distinction from the LM13600 that improves DC stability in audio applications.

Key Specifications

Pinout & Package

LM13700M/NOPB is housed in a 16-pin SOIC package (3.91 mm × 9.90 mm body size) with standard JEDEC MS-012AC footprint and 1.27 mm pitch. Thermal resistance is RθJA = 83.0°C/W, requiring moderate PCB copper area for operation above 25°C ambient.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar operational transconductance amplifier applications.

Compared with LM13700M/NOPB, LM13600N/NOPB offers identical pinout but inferior gm tracking and buffer DC stability, while CA3080E demands external circuitry to match basic LM13700M/NOPB functionality - making LM13700M/NOPB the optimal choice for integrated, low-THD analog signal control.

Availability

LM13700M/NOPB is available at Aetrix Electronics and suitable for stereo audio amplifiers, voltage-controlled oscillators, current-controlled filters, and automatic gain control circuits requiring stable component supply across industrial and pro-audio production lifecycles.

Supply support for LM13700M/NOPB includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor leader specializing in analog and embedded processing technologies, with over 50 years of innovation in precision analog ICs.

The LM13700M/NOPB belongs to TI's legacy analog signal processing portfolio, engineered specifically for voltage-controlled analog functions including audio synthesis, programmable filtering, and real-time gain modulation.

FAQ

What is the maximum supply voltage for LM13700M/NOPB?

The LM13700M/NOPB supports an absolute maximum supply voltage of ±18 V (36 V total), with recommended dual-supply operation between ±4.75 V and ±16 V. Exceeding ±18 V risks permanent damage, and thermal derating is required above 25°C ambient due to its SOIC package's 83.0°C/W junction-to-ambient resistance. Always verify operating conditions against TI's SNOSBW2F datasheet revision F.

How does the linearizing diode function improve LM13700M/NOPB performance?

The linearizing diodes (pins 2/15) in LM13700M/NOPB reduce harmonic distortion by compensating for exponential transistor transfer characteristics, enabling ±60 mVpp differential input at <0.1% THD - a 10 dB improvement over non-linearized OTAs. This allows larger input signals without clipping, directly enhancing signal-to-noise ratio in audio and instrumentation applications where LM13700M/NOPB is deployed.

Can LM13700M/NOPB operate from a single supply?

Yes, LM13700M/NOPB supports single-supply operation from 9.5 V to 32 V, with V− tied to ground and V+ connected to the positive rail. Input common-mode range extends to within 1.5 V of either rail, and buffer outputs swing to ±12 V relative to V−. Designers must ensure IABC and ID bias networks reference appropriate DC levels - e.g., diode bias at ~0.7 V above ground - to maintain linearity in LM13700M/NOPB single-supply configurations.

What is the purpose of the separate buffer inputs (pins 7/10) in LM13700M/NOPB?

The buffer inputs (pins 7/10) in LM13700M/NOPB provide high-impedance access to the Darlington output stage, isolating the sensitive OTA core from capacitive loading and output-stage nonlinearities. Unlike the LM13600, LM13700M/NOPB's buffer input bias current is independent of IABC - preventing gain-induced DC offset shifts and ensuring stable quiescent points in precision analog circuits using LM13700M/NOPB.

How does LM13700M/NOPB differ from LM13600 in practical design?

LM13700M/NOPB differs from LM13600 primarily in buffer input bias independence from IABC and tighter gm tracking (0.3 dB vs. unspecified), resulting in superior DC stability and channel matching for stereo audio and dual-path filters. LM13700M/NOPB also features enhanced thermal metrics (RθJA = 83.0°C/W vs. 43.8°C/W for PDIP LM13600N) and updated ESD ratings per SNOSBW2F revision F - making LM13700M/NOPB the preferred choice for new designs demanding predictable analog behavior.