THS4031IDGNR - 100MHz Low-Noise VFB Amplifier | Texas Instruments
MPN: THS4031IDGNR ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $5.26 | $5.26 |
| 10 | $4.72 | $47.20 |
| 100 | $3.87 | $387.00 |
| 500 | $3.29 | $1,645.00 |
| 1,000 | $2.78 | $2,780.00 |
Drop-in alternatives for THS4031IDGNR — 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:
THS4031IDGNRG4
✅ Drop-In📋 Reference alternative (not in catalog)
THS4031IDGN
✅ Drop-In📋 Reference alternative (not in catalog)
THS4031CDGNR
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$1.62 / Unit
View Datasheet →THS4031CDGNG4
✅ Drop-In📋 Reference alternative (not in catalog)
THS4032IDGNR
✅ Drop-In📋 Reference alternative (not in catalog)
THS4021CDGNR
✅ Drop-In📋 Reference alternative (not in catalog)
THS4031IDGNR Maximum Ratings & Electrical Characteristics
| Amplifier Type | Voltage Feedback Amplifier |
| Number of Channels | 1 |
| Bandwidth | 100 MHz (G = -1) |
| Slew Rate | 100 V/us |
| Input Voltage Noise | 1.6 nV/sqrt(Hz) |
| Input Offset Voltage | 0.5 mV (typ) |
| THD at 1 MHz (low-Z load) | -72 dBc |
| THD at 1 MHz (1 kOhm load) | -90 dBc |
| Output Current | 90 mA |
| Supply Voltage Range | +-4.5 V to +-16 V |
| Stability | Stable in gains of 1 V/V or greater |
| Operating Temperature Range | -40C to +85C (I grade) |
| Package | 8-HVSSOP (DGN) with PowerPAD |
| Number of Pins | 8 |
| Mounting Type | Surface Mount |
| RoHS Status | RoHS3 Compliant |
THS4031IDGNR Pin Configuration
| Pin 1 | OUT — Amplifier output |
| Pin 2 | -IN — Inverting input |
| Pin 3 | +IN — Non-inverting input |
| Pin 4 | V- — Negative supply |
| Pin 5 | NC — Not connected (per datasheet) |
| Pin 6 | NC — Not connected (per datasheet) |
| Pin 7 | V+ — Positive supply |
| Pin 8 | NC — Not connected (per datasheet); PowerPAD on underside soldered to ground plane for thermal dissipation |
Safe Operating Area (SOA) & Thermal Characteristics
No official SOA curve available for this component. Always operate within absolute maximum ratings specified in the datasheet. Ensure adequate cooling and derate as needed.
Typical Applications
THS4031IDGNR is suitable for 6 applications: High-Speed ADC Input Driver, Communications Receiver IF Gain Blocks, Ultrasound and Imaging Front Ends, Test and Measurement Instrumentation, Video and Wideband Signal Distribution, Active Filter and Signal Conditioning Stages.
High-Speed ADC Input Driver
The THS4031IDGNR excels as an ADC driver because its 1.6 nV/√Hz input noise adds negligible noise to the ADC's own aperture and thermal noise budget, preserving effective-number-of-bits (ENOB) in 12- to 16-bit pipelines sampling at tens of MHz. Placed directly in front of the ADC with an RC filter between amplifier output and sampling capacitor, the 100 MHz bandwidth settles quickly between conversion steps, while the 90 mA output current easily charges typical ADC input capacitance through the filter resistor. The voltage-feedback topology allows classic resistor-ratio gain setting, so the engineer can match the signal span to the ADC full-scale range precisely. Using the DGN PowerPAD soldered to the ground plane keeps junction temperature low during continuous high-frequency drive.
Recommended
Communications Receiver IF Gain Blocks
In communications receivers, the IF chain demands amplifiers whose noise floor does not degrade the cascaded noise figure. The THS4031IDGNR's 1.6 nV/√Hz voltage noise, when referred through a typical 50- to 200-ohm IF impedance, contributes minimally compared with source thermal noise, making it well suited to IF gain stages between mixers and ADCs. The 100 MHz bandwidth covers wideband IF bandwidths well beyond typical 10-50 MHz IF channels, and the -72 dBc distortion at 1 MHz keeps intermodulation products below the dynamic range targets of multi-carrier receivers. Its operation from ±5 V or ±15 V rails lets designers reuse the same gain-block design across battery-powered radios and rack-mounted test receivers.
Recommended
Ultrasound and Imaging Front Ends
Medical ultrasound and CCD/CMOS imaging chains are exactly the applications TI cites for the THS403x family. Piezo transducer and photodiode signals are small and bandwidth-rich, so the front-end amplifier's 1.6 nV/√Hz noise directly determines the smallest detectable echo or pixel charge. The THS4031IDGNR's 100 MHz bandwidth preserves the fast transducer ring-down edges needed for axial resolution, and its low 0.5 mV typical offset keeps DC levels stable across long receive windows. Time-gain-compensation (TGC) stages implemented with THS4031 gain blocks maintain consistent bandwidth as gain varies, because the voltage-feedback architecture keeps the gain-bandwidth product constant. The PowerPAD package handles the duty-cycle heat of pulsed transmit/receive operation.
Recommended
Test and Measurement Instrumentation
Oscilloscope, spectrum analyzer, and arbitrary-waveform front ends benefit from the THS4031IDGNR's combination of 100 MHz bandwidth, 100 V/us slew rate, and -90 dBc distortion into 1 kΩ loads at 1 MHz. Input attenuator/preamp stages built with the THS4031 maintain flat gain across the band, and the ±4.5 V to ±16 V supply range allows designs referenced to traditional ±15 V instrument rails without redesign. The 0.5 mV typical input offset minimizes baseline drift that would otherwise require periodic auto-zero calibration. Because the device is stable at unity gain, it can also serve as the final low-impedance buffer driving 50-ohm back-terminated outputs, using its 90 mA output current capability.
Recommended
Video and Wideband Signal Distribution
Composite and component video, plus general 75-ohm distribution systems, require amplifiers with low differential gain and phase error and enough current to drive back-terminated lines. The THS4031IDGNR's -72 dBc distortion at 1 MHz into low-impedance loads translates to clean video harmonics, and its 90 mA output supports 75-ohm back-terminated drive at standard video levels. The 100 MHz bandwidth far exceeds the 8-40 MHz requirements of high-definition video formats, ensuring minimal pulse ringing and overshoot. Designers typically configure the THS4031 with a gain of 2 V/V to compensate the 6 dB back-termination loss, well within its unity-gain-stable operating envelope, while the DGN PowerPAD thermal path keeps die temperature controlled during continuous broadcast duty.
Recommended
Active Filter and Signal Conditioning Stages
Wideband active filters (multiple-feedback and Sallen-Key topologies) require amplifiers whose open-loop bandwidth is at least an order of magnitude above the filter corner to keep the actual response close to the transfer-function prediction. With 100 MHz bandwidth, the THS4031IDGNR supports filters with corners into the tens of MHz while holding Q accuracy, and the low 1.6 nV/√Hz noise keeps the filter's output noise floor low for follow-on gain stages. The stable-at-gain-1-or-greater specification suits Sallen-Key unity-gain sections directly. Resistor values should be kept moderate (hundreds of ohms to a few kilohms) so stray capacitance does not move pole locations, and the ±5 V supply option simplifies integration into mixed-signal boards.
Recommended
Recommended Products Summary
Engineering reference data for THS4031IDGNR — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | THS4031IDGNRG4 | THS4031IDGN | THS4031CDGNR | THS4032IDGNR | THS4021CDGNR |
|---|---|---|---|---|---|---|
| Package | 8-HVSSOP (DGN) PowerPAD | 8-HVSSOP (DGN) - same | 8-HVSSOP (DGN) - same | 8-HVSSOP (DGN) - same | 8-HVSSOP (DGN) - same | 8-HVSSOP (DGN) - same |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Bandwidth | 100 MHz (G = -1) | 100 MHz | 100 MHz | 100 MHz | 100 MHz per channel | [DATA_NEEDED] |
| Input Voltage Noise | 1.6 nV/√Hz | 1.6 nV/√Hz | 1.6 nV/√Hz | 1.6 nV/√Hz | 1.6 nV/√Hz per channel | [DATA_NEEDED] |
| Slew Rate | 100 V/us | 100 V/us | 100 V/us | 100 V/us | 100 V/us | [DATA_NEEDED] |
| Operating Temperature | -40C to +85C (I grade) | -40C to +85C | -40C to +85C | 0C to +70C (C grade) | -40C to +85C | 0C to +70C (C grade) |
| Channels | 1 | 1 | 1 | 1 | 2 (dual, different pin functions) | 1 |
| Supply Voltage Range | +-4.5 V to +-16 V | +-4.5 V to +-16 V | +-4.5 V to +-16 V | +-4.5 V to +-16 V | +-4.5 V to +-16 V | [DATA_NEEDED] |
Key Differentiators
- Ultra-low 1.6 nV/√Hz voltage noise in a voltage-feedback topology (vs THS4021CDGNR)
- Single-channel pin map preserved vs dual version (vs THS4032IDGNR)
- Industrial temperature range at commercial price (vs THS4031CDGNR)
- Unity-gain-stable voltage feedback vs current-feedback parts (vs THS4021CDGNR)
Design Notes
The 8-HVSSOP (DGN) PowerPAD package relies on the exposed pad under the die for heat removal. Solder the PowerPAD directly to a solid ground plane with an array of thermal vias (typically 5x5 via pattern recommended in TI PowerPAD application notes). Estimated: at ±15 V supplies with a 10 mA quiescent-class load plus 50 mA output current, dissipation can approach 1.5-2 W, and an unsoldered PowerPAD raises junction temperature dramatically versus the datasheet theta-JA figure, which assumes a properly soldered pad. Verify junction temperature with your actual supply, load, and ambient conditions.
Place supply decoupling capacitors (0.1 uF ceramic in parallel with 2.2-6.8 uF per rail) within 2-3 mm of the V+ and V- pins, connected to a low-impedance ground return. At 100 MHz bandwidth, even a few nanohenries of trace inductance degrades PSRR and can permit high-frequency oscillation. Keep the feedback path short, remove ground plane under the inverting input node to reduce stray capacitance (which lowers phase margin in VFAs), and use a ground plane cutout only where the sensitive nodes run.
The 100 MHz bandwidth is specified at a gain of -1 V/V; at a noise gain of 10, closed-loop bandwidth drops to roughly one-tenth (gain-bandwidth product behavior). Budget bandwidth at your actual noise gain, not at unity gain. Also, the part is stable only for noise gains of 1 V/V or greater - do not configure noise gains below unity. Finally, when substituting the dual THS4032IDGNR on the same footprint, remember the pin functions differ (two channels share the package), so a single-channel layout must be re-verified.
For driving 50-ohm or 75-ohm cables, use a series back-termination resistor at the amplifier output and accept the 6 dB loss, setting closed-loop gain to 2 V/V to compensate. The 90 mA output current supports this at moderate swings from ±5 V or higher rails. Source-terminate rather than double-terminate directly at the amplifier output when full swing is needed, and check the datasheet distortion curves at your specific load and frequency to confirm harmonic levels meet system requirements.
Compliance Information
Distributor records list ROHS3 compliant and lead-free status for THS4031IDGNR. REACH and halogen-free declarations not found in provided data; consult TI environmental pages.
