LME49600TS/NOPB - 110MHz High-Current Headphone Buffer | TI
MPN: LME49600TS/NOPB ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $6.5 | $6.50 |
| 10 | $5.85 | $58.50 |
| 100 | $5.2 | $520.00 |
| 500 | $4.55 | $2,275.00 |
| 1,000 | $3.95 | $3,950.00 |
LME49600TS/NOPB Overview
A buffer is a unity-gain (or near unity-gain) current amplifier that sits between a low-power op-amp or DAC output and a low-impedance load. Buffers multiply the available drive current without significantly altering voltage gain, and they are categorized within the broader hierarchy of operational amplifiers -> amplifiers -> analog signal-chain ICs. The LME49600 specifically addresses high-fidelity audio where the combination of wide bandwidth, high slew rate, and high output current into 32 ohm headphones is critical to preserving waveform integrity.
Key features include pin-selectable bandwidth (7.3 mA quiescent current at 110 MHz versus 13.2 mA at 180 MHz), low total harmonic distortion plus noise, an enable/disable pin, and a wide ±2.25 V to ±18 V dual supply range. The DDPAK-5 power package with an exposed thermal pad supports the high continuous dissipation required when driving low-impedance loads, while the small surface-mount footprint simplifies PCB integration in space-constrained audio products.
The LME49600 is built on a bipolar complementary (push-pull) output architecture optimized for high-current linear operation. The internal design minimizes crossover distortion and offers a high slew rate that preserves square-wave and high-frequency music content. Designers can place the LME49600 inside or outside an op-amp's feedback loop, enabling flexible topology choices from simple buffers to composite amplifiers with substantially higher output current than the host op-amp alone.
Typical applications include headphone amplifiers for studio monitors and audiophile consumer gear, professional line drivers for mixing consoles, op-amp current boosters for ADC drivers, audio DAC output stages, and test-and-measurement instrumentation requiring low-distortion high-current signal delivery.
When designing with the LME49600, pay attention to PCB thermal management. Estimated: at a 12 V supply driving 32 ohm headphones at full ±7 V swing, continuous dissipation in the TO-263 package may exceed 1 W, so a copper pour and thermal vias under the exposed pad are mandatory for reliability.
Drop-in alternatives for LME49600TS/NOPB — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with LME49600TS/NOPB (same form factor and footprint) — differing in Mounting Type, Output Type, Package.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
LME49600TS
✅ Drop-In📋 Reference alternative (not in catalog)
LME49600TS/NOPB
✅ Drop-In✓ In Stock
$3.95 / Unit
View Datasheet →LM3886TF
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$4.78 / Unit
View Datasheet →LME49600TS/NOPB Maximum Ratings & Electrical Characteristics
| Function | Headphone buffer (current amplifier) |
| Number of Channels | 1 (Mono) |
| Output Type | Class AB, push-pull |
| Bandwidth (Low-Current Mode) | 110 MHz |
| Bandwidth (Wide-Bandwidth Mode) | 180 MHz |
| Slew Rate (Nominal) | 2000 V/us |
| Supply Voltage Range (Dual) | ±2.25 V to ±18 V |
| Output Current | ±250 mA |
| Output Voltage Swing | ±7.5 V (typical) |
| Quiescent Current (110 MHz Mode) | 7.3 mA |
| Quiescent Current (180 MHz Mode) | 13.2 mA |
| Operating Temperature | -40 C to +85 C |
| Package | TO-263 (DDPAK-5, KTT) 5-pin |
| Mounting Type | Surface Mount |
| MSL Level | 3 (per distributor data) |
| RoHS Status | Compliant |
| Enable Pin | Yes (per datasheet description) |
LME49600TS/NOPB Pin Configuration
| Pin 1 | INPUT — Buffer input (non-inverting unity gain) |
| Pin 2 | VCC — Positive supply (+2.25 V to +18 V) |
| Pin 3 | VEE — Negative supply (-2.25 V to -18 V) |
| Pin 4 | OUTPUT — Buffer output (drives ±250 mA into load) |
| Pin 5 | BW / EPAD — Bandwidth-select pin and exposed thermal pad (ground-referenced for thermal dissipation) |
Typical Applications
LME49600TS/NOPB is suitable for 6 applications: Audiophile Headphone Amplifier, Professional Line Driver / Mixing Console Output, Audio DAC Output Buffer Stage, ADC Driver / Test & Measurement Front End, Op-Amp Current Booster Inside Feedback Loop, Studio Monitor Power Amplifier Output Stage.
Audiophile Headphone Amplifier
The LME49600TS/NOPB is a strong fit for audiophile headphone amplifiers driving 32 ohm to 600 ohm headphones from a precision op-amp (such as OPA1612 or LME49720). With ±250 mA output current, 110 MHz / 180 MHz pin-selectable bandwidth, and 2000 V/us slew rate, the buffer adds negligible distortion while multiplying the op-amp's drive capability, enabling wide dynamic range at high SPLs. Designers typically place it inside the op-amp feedback loop (BOOM topology) so that the composite amp inherits the op-amp's DC accuracy and the buffer's current swing; the 7.3 mA / 13.2 mA quiescent modes let engineers trade idle power for extended treble response in line with the headphone's impedance curve.
Recommended
Professional Line Driver / Mixing Console Output
In professional line-driver and mixing-console output stages the LME49600TS/NOPB delivers the high current and wide bandwidth required to drive long cable runs and balanced line inputs without slew-rate-induced distortion. The device's ±7.5 V swing and 110 MHz bandwidth cover the full audio band plus significant headroom for inter-sample peaks in digital audio. The DDPAK-5 package with exposed thermal pad handles the sustained dissipation typical of multi-channel console designs; designers commonly parallel two LME49600 buffers for differential balanced outputs, exploiting their matched bandwidth to preserve common-mode rejection through the output stage.
Recommended
Audio DAC Output Buffer Stage
Placed between an audio DAC's current-output stage and the next stage (I/V converter or headphone amp), the LME49600TS/NOPB acts as a high-current, low-impedance buffer that preserves the DAC's transient response. The 2000 V/us slew rate and 110-180 MHz bandwidth prevent the buffer from rolling off high-frequency music content or contributing intermodulation distortion. This makes the device attractive for high-performance USB DACs, network streamers, and S/PDIF receiver boards where the output must drive 32 ohm headphones directly while remaining transparent to the DAC's I-V stage. The exposed-pad TO-263 package enables compact PCB layouts in slim consumer enclosures.
Recommended
ADC Driver / Test & Measurement Front End
In ADC driver and test-and-measurement front ends the LME49600TS/NOPB provides the high slew rate and wide bandwidth required to settle quickly into the ADC's input capacitance, preserving SFDR and SINAD on fast step inputs. The buffer's ±250 mA output current enables direct drive of low-impedance ADC input networks and high-frequency probes. Designers benefit from the dual bandwidth-select mode: 110 MHz for low-power benchtop instruments, 180 MHz for wideband data-acquisition and RF-sampling ADCs. The DDPAK-5 footprint supports dense multi-channel data-acquisition boards where each channel needs an independent buffer.
Recommended
Op-Amp Current Booster Inside Feedback Loop
The LME49600TS/NOPB is purpose-built to sit inside the feedback loop of a low-power op-amp, multiplying its output current without disturbing its DC accuracy. This 'BOOM' (buffered op-amp) topology is the canonical way to upgrade an OPA1612-class op-amp into a high-current ±250 mA amplifier, retaining the op-amp's offset, noise, and PSRR while gaining the buffer's drive. The composite amplifier preserves the op-amp's small-signal behavior at unity gain and adds the buffer's bandwidth only where the load requires it. This topology is widely used in instrumentation, audio power amplifiers, and precision motor-drive signal chains.
Recommended
Studio Monitor Power Amplifier Output Stage
Active studio monitors and high-end powered speakers benefit from the LME49600TS/NOPB as a high-current output stage for mid-power amplifier modules. While the LME49600 is more typically a buffer than a power amplifier, its ±250 mA and ±7.5 V swing allow small near-field monitors to be built with multiple LME49600s in parallel-BTL configurations, yielding low distortion at moderate SPLs. The 180 MHz wide-bandwidth mode preserves phase accuracy through the crossover region, and the bipolar ±18 V supply capability supports the higher rail voltages common in studio-monitor power supplies.
Recommended
Recommended Products Summary
Engineering reference data for LME49600TS/NOPB — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | LME49600TS | LME49600TS/NOPB (reel) | LM3886TF |
|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | TO-263-5 (DDPAK, KTT) | TO-263-5 (DDPAK, KTT) - same | TO-263-5 (DDPAK, KTT) - same | TO-220-11 - different package |
| Function | Headphone buffer (current amplifier) | Headphone buffer | Headphone buffer | 68 W audio power amplifier |
| Output Current | ±250 mA | ±250 mA | ±250 mA | up to ±6 A continuous |
| Bandwidth | 110 MHz / 180 MHz selectable | 110 MHz / 180 MHz selectable | 110 MHz / 180 MHz selectable | 20 Hz - 20 kHz audio |
| Slew Rate | 2000 V/us | 2000 V/us | 2000 V/us | 19 V/us |
| Supply Voltage | ±2.25 V to ±18 V | ±2.25 V to ±18 V | ±2.25 V to ±18 V | ±10 V to ±42 V |
| RoHS Status | Compliant (Pb-free /NOPB finish) | Non-RoHS (SnPb finish) | RoHS compliant | RoHS compliant |
Key Differentiators
- Pin-selectable 110 MHz / 180 MHz bandwidth with 2000 V/us slew rate (vs BUF634)
- Designed specifically for inside-loop op-amp boosting (vs LM3886TF)
- TO-263-5 power package with exposed thermal pad (vs BUF634 (5-pin TO-220/TO-263 variants))
Design Notes
Estimated thermal design: at ±15 V supplies driving 32 ohm headphones at full ±7 V swing, continuous dissipation in the LME49600 may exceed 1 W and approach the package limit. Use a minimum 1 square-inch copper pour on the TO-263 exposed pad with at least 9 thermal vias (0.3 mm hole, 1 mm pitch) connecting to internal ground planes. Without adequate thermal relief the die may exceed 125 C junction temperature at sustained full output, activating thermal shutdown or degrading long-term reliability.
Place VCC and VEE decoupling capacitors (typically 0.1 uF ceramic + 10 uF electrolytic) as close as possible to pins 2 and 3 of the TO-263-5 footprint. Keep input (pin 1) and output (pin 4) traces short and matched to minimize parasitic inductance and preserve the 110 MHz / 180 MHz bandwidth. The exposed pad must be soldered to a copper pour; if not, thermal dissipation drops sharply and the device may enter thermal shutdown under load.
Do not operate the LME49600 below ±2.25 V supplies - the output stage will not swing to its rated ±7.5 V and severe distortion may result. Avoid using single-supply operation without a virtual ground; the device is bipolar and the input/output reference expects symmetric rails. The bandwidth-select pin must be tied to a defined logic level (VEE for 110 MHz mode, VCC for 180 MHz mode) or the part may operate in an undefined bias state.
When using the LME49600 inside the feedback loop of a precision op-amp (BOOM topology), the composite amplifier's unity-gain bandwidth is dominated by the host op-amp, while the buffer's 2000 V/us slew rate determines large-signal behavior. Ensure the op-amp's phase margin at unity gain remains above 60 degrees after the buffer is inserted; compensation capacitors on the host op-amp may need to be increased by 2x to 3x to compensate for the buffer's additional propagation delay.
Compliance Information
RoHS compliance per /NOPB suffix in TI ordering nomenclature. Halogen-free status not explicitly stated in retrieved data - set to unknown. AEC-Q100 not applicable for this audio-grade IC; this is a commercial/industrial-grade part per the -40 C to +85 C operating range.
