OPA699M - Gain +4 Stable Voltage Limiting Amplifier | TI
MPN: OPA699M ✓ Active| Qty | Unit Price | Extended |
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OPA699M Overview
A voltage limiting amplifier is a specialized op amp that clamps its output voltage to externally defined positive and negative levels, protecting downstream circuitry such as ADCs and comparators from overdrive. In the signal-chain hierarchy, the OPA699M sits between general-purpose high-speed op amps and dedicated limiters, combining wideband amplification with an integrated limiting function.
Key features include independent bipolar output limiting with fast recovery time, high slew rate, and low distortion when returning from a limited state. The device offers a typical bandwidth of 200 MHz at gain +4, operates from dual supplies of ±5V to ±12V, and delivers up to ±80 mA of output current, allowing it to drive low-impedance loads and transmission lines directly.
Architecturally, the OPA699M uses a voltage-feedback topology with a wideband input stage and external clamp resistors that set the limit thresholds, giving designers flexibility to align limiting levels with system requirements. The ceramic CDIP-8 package provides hermeticity and thermal robustness required in military and aerospace platforms.
Typical applications include high-speed ADC drivers, video distribution and line drivers, pulse amplifiers, radar and communications receivers, and test instrumentation - anywhere signal overshoot must be bounded while preserving bandwidth.
Design tip: use precision resistors to set the clamp levels and minimize parasitic capacitance at the output node to optimize recovery time; adequate supply decoupling is essential for stability at high gain.
Drop-in alternatives for OPA699M — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
OPA698M
⚡ Same Package📋 Reference alternative (not in catalog)
OPA699
⚡ Same Package📋 Reference alternative (not in catalog)
OPA699M Maximum Ratings & Electrical Characteristics
| Amplifier Type | Wideband voltage-feedback op amp with output limiting |
| Stable Minimum Gain | +4 V/V |
| Output Limiting | Bipolar, externally set |
| Bandwidth | 200 MHz (typical at gain +4) |
| Supply Voltage Range | ±5 V to ±12 V |
| Output Current | ±80 mA |
| Recovery Time | Fast (value in datasheet) |
| Operating Temperature Range | -55C to +125C |
| Package | CDIP-8 |
| Mounting Type | Through Hole |
| Pinout | Industry-standard 8-pin |
| Number of Channels | 1 |
| Military Grade | Yes (M suffix) |
| RoHS Status | unknown (ceramic/military package, verify) |
OPA699M Pin Configuration
| Pin 1 | [DATA_NEEDED: pin 1 function] — See TI OPA699M datasheet pin configuration |
| Pin 2 | IN- — Inverting input |
| Pin 3 | IN+ — Non-inverting input |
| Pin 4 | V- — Negative supply |
| Pin 5 | [DATA_NEEDED: pin 5 function] — See TI OPA699M datasheet (limiting function) |
| Pin 6 | OUT — Limited amplifier output |
| Pin 7 | V+ — Positive supply |
| Pin 8 | [DATA_NEEDED: pin 8 function] — See TI OPA699M datasheet |
Typical Applications
OPA699M is suitable for 6 applications: High-Speed ADC Driver, Pulse and Video Amplification, Military and Aerospace Signal Conditioning, Radar and Communications Receivers, Test and Measurement Instrumentation, Comparator and Threshold Protection Circuits.
High-Speed ADC Driver
The OPA699M fits ADC front ends where the input can overshoot or fault: its bipolar output limiting clamps the drive to a safe window, protecting the converter's input stage, while 200 MHz bandwidth at gain +4 and ±80 mA output current support fast settling into switched-capacitor ADC inputs. Place the amplifier close to the converter with a short series resistor, and program clamp levels just beyond the ADC's rated input span using precision resistors. Unlike a diode-clamped standard op amp stage, the integrated limiter recovers quickly and symmetrically, minimizing distortion after an overdrive event.
Recommended
Pulse and Video Amplification
In pulse and video paths, the OPA699M's bounded output prevents amplitude overshoot from propagating to threshold detectors or cables, while its fast recovery preserves pulse fidelity after clipping. The +4-stable wideband stage supports gain blocks in distribution amplifiers, and the ±80 mA drive capability directly backs 50-ohm and 75-ohm transmission lines without an additional buffer. Set the clamp levels to the line's maximum legal amplitude; this yields a cleanly limited composite output. The trade-off versus an unlimiting video amp is a slightly higher quiescent current and the need to route clamp resistors carefully.
Recommended
Military and Aerospace Signal Conditioning
The M-grade OPA699M in hermetic CDIP-8 is specified from -55C to +125C, matching defense, avionics, and space-adjacent program requirements where plastic-packaged amplifiers are not acceptable. The ceramic package resists moisture ingress and supports conformal coating and screening flows. Its ±5V to ±12V dual-supply range matches legacy military ±12V/±15V rails with derating, and the industry-standard pinout eases second-source layouts within TI's family. Use the OPA699M wherever an analog chain must both amplify wideband signals and guarantee bounded outputs under sensor fault conditions over full military temperature.
Recommended
Radar and Communications Receivers
Receiver IF and baseband chains benefit from the OPA699M's combination of 200 MHz gain-+4 bandwidth and hard output limiting: strong incoming signals are clipped to a defined amplitude, protecting mixers, log detectors, or ADCs downstream, and the fast recovery ensures weak signals immediately following a strong burst are not lost to saturation tails. Program symmetric clamp levels around the desired IF amplitude, and keep clamp-node parasitics low to preserve recovery time. Compared with diode limiters, the integrated limiting amplifier provides a sharper, more temperature-stable clip threshold.
Recommended
Test and Measurement Instrumentation
Bench instruments such as pulse generators, oscilloscope front ends, and signal conditioners use the OPA699M to deliver known, bounded amplitudes: the external clamp network lets a design present calibrated maximum output levels independent of supply variation, and the ±80 mA output drives cables and heavy loads directly. The military temperature rating and hermetic CDIP-8 also support instrumentation destined for outdoor or rack environments with wide ambient swings. Keep the clamp resistor network shielded and use low-noise supplies to avoid coupling clamp transients into the measurement path.
Recommended
Comparator and Threshold Protection Circuits
Where an op amp drives a comparator, FPGA pin, or logic translator, the OPA699M's bipolar limiting guarantees the drive never exceeds the programmed window, eliminating the need for external clamp diodes and their leakage and capacitance penalties. The 200 MHz bandwidth supports fast edge amplification from sensor or receiver outputs, and recovery is quick enough for repetitive pulsed comparisons. Set the clamps to the comparator's common-mode-safe range, verify the limited-state impedance per the datasheet, and decouple supplies locally to prevent clamp transients from disturbing nearby logic thresholds.
Recommended
Recommended Products Summary
Engineering reference data for OPA699M — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | OPA698M | OPA699 |
|---|---|---|---|
| Package | CDIP-8 | CDIP-8 - same | SOIC-8 - different package |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments |
| Minimum Stable Gain | +4 V/V | Lower gain optimized | +4 V/V |
| Output Limiting | Bipolar, externally set | Bipolar, externally set | Bipolar, externally set |
| Recovery From Limit | Fast | Fast | Fast |
Key Differentiators
- Integrated bipolar output limiting with fast recovery (vs OPA698M)
- Military-grade hermetic CDIP-8 packaging (vs OPA699)
- Wideband 200 MHz class performance with protection (vs Standard high-speed op amps (e.g., OPA2670))
Design Notes
Set the bipolar output clamp levels with precision (1% or better) resistors per the TI OPA699M datasheet clamp network. Clamp accuracy depends directly on resistor tolerance and the voltage reference feeding the network. Do not exceed the programmed clamp headroom relative to the ±5V to ±12V supplies - if the clamp level approaches a rail, limiting accuracy degrades. Also confirm your closed-loop gain is +4 V/V or higher; below this the amplifier is not guaranteed stable.
Minimize parasitic capacitance at the output node to preserve fast recovery time when exiting the limited state - keep the output trace short and avoid routing clamp resistor networks directly over ground pours that add capacitance. Use a solid ground plane, place 0.1uF ceramic decoupling capacitors within 5 mm of the V+ and V- pins (7 and 4) with a bulk 4.7uF nearby, and return clamp network grounds at a single low-impedance point.
The hermetic CDIP-8 has modest thermal performance; with ±80 mA output drive into low-impedance loads, compute junction temperature from worst-case load current and supply headroom, and use generous copper traces from the package leads as heatsinking. In -55C to +125C military environments, derate output current at high ambient per the datasheet derating curve rather than assuming full ±80 mA capability across the entire range.
Compliance Information
Military-grade hermetic ceramic CDIP-8 part; compliance data not present in provided sources - verify with TI product page before procurement.
