LM2596S-ADJ/NOPB vs LTM8074IY#PBF: Component Comparison
Quick verdict
For applications requiring up to 3A output current with a simple, cost-effective solution and a wide input voltage range, the LM2596S-ADJ/NOPB is the better choice due to its higher current capability and straightforward buck topology. However, for compact designs where PCB space is at a premium, and moderate current (up to 1.2A) with integrated power stage and higher switching frequency is acceptable, the LTM8074IY#PBF µModule regulator offers significant integration and thermal advantages.
Spec comparison table
| Spec | LM2596S-ADJ/NOPB | LTM8074IY#PBF | Notes |
|---|---|---|---|
| Function | Step-Down Buck Regulator | Non-Isolated Point-of-Load (PoL) Module | Both step-down, LTM8074 integrates more components internally. |
| Input Voltage Min (V) | 4.5 | 3.2 | LTM8074 supports lower input voltage, better for low-voltage rails. |
| Input Voltage Max (V) | 40 | 40 | Equal input voltage range. |
| Output Voltage Min (V) | 1.2 | 0.8 | LTM8074 supports lower output voltage, useful for low-voltage digital cores. |
| Output Voltage Max (V) | 37 | 12 | LM2596 supports much higher max output voltage; LTM8074 limited to 12V max. |
| Output Current Max (A) | 3 | 1.2 | LM2596 supports 2.5x higher output current. |
| Peak Output Current (A) | Not specified | 1.75 | LTM8074 can provide short bursts above nominal current. |
| Number of Outputs | 1 | 1 | Both single output. |
| Switching Frequency (typ) | 150 kHz | 850 kHz (typ), up to 2.2 MHz max | LTM8074’s higher frequency enables smaller inductors/capacitors but may increase EMI. |
| Synchronous Rectification | No | Yes (implied by integration, typical for µModules) | LM2596 uses diode rectification, less efficient at low output voltages. |
| Package Type | TO-263-6, D2PAK (5 Leads + Tab) | 25-FBGA (4x4 mm) | LTM8074 is a compact µModule, LM2596 larger discrete IC. |
| Mounting Type | Surface Mount | Surface Mount | Both surface mount, but very different package size and thermal characteristics. |
| Operating Temperature Range (TJ) | -40°C to 125°C | -40°C to 125°C | Equal operating temperature range. |
| Efficiency (min) | Not specified | 80% min | LTM8074 datasheet specifies minimum efficiency, LM2596 datasheet does not. |
| Quiescent Current (typ) | Not specified | 3 µA | LTM8074 has very low quiescent current, good for low power standby. |
| Output Voltage Ripple (typ) | Not specified | 15 mV | LTM8074 provides ripple data; LM2596 ripple depends on external components. |
| Thermal Resistance (Junction-to-Ambient) | Not specified | 48.9°C/W | LTM8074 thermal resistance known, helps in thermal design. |
| Thermal Resistance (Junction-to-Case Bottom) | Not specified | 17.2°C/W | LTM8074’s thermal path through PCB for heat sinking is defined. |
| Package Weight | Not specified | 0.08g | LTM8074 is very lightweight, suitable for dense boards. |
| Soft-Start/Tracking | Not specified | Yes, programmable via capacitor | LTM8074 allows soft-start control, useful for sequencing. |
| Power Loss Max | Not specified | 3000 mW | LTM8074 specifies max power loss, useful for thermal budgeting. |
| Input Current Typ | Not specified | 1.2 A | LTM8074 input current specified, useful for input power supply design. |
| Control Features | Basic | Burst mode, pulse-skipping, spread spectrum, synchronization | LTM8074 offers advanced switching modes and synchronization options. |
| Board Size (recommended) | Not specified | 58 cm² | LTM8074 requires a relatively large board area for thermal and layout reasons. |
| Soft-Start Ramp Time | Not specified | t = 0.39 × C (µF) sec | LTM8074 soft start is programmable. |
| Power Good Threshold | Not specified | 90% min - 110% max | LTM8074 provides power-good indication, useful for system monitoring. |
| Switching Frequency Range | Fixed ~150 kHz | 200 kHz min to 2.2 MHz max | LTM8074 allows frequency programming, helpful to avoid EMI bands. |
Design trade-offs
The LM2596S-ADJ/NOPB is a classic, discrete buck regulator IC with a wide input voltage range up to 40V and a maximum output current of 3A, which makes it suitable for moderately high current loads. Its fixed switching frequency of 150 kHz is relatively low, meaning inductors and capacitors are larger but generally easier to source and design for EMI. The lack of synchronous rectification means efficiency suffers at lower output voltages and higher currents due to diode forward voltage losses, and thermal dissipation must be carefully managed with a proper heat sink or thermal vias on the PCB. The TO-263 package with a large tab allows for decent heat sinking but requires a relatively large PCB footprint.
In contrast, the LTM8074IY#PBF is a µModule regulator that integrates the switching controller, power stage MOSFETs, and passive components into a compact 4x4 mm BGA package. Its switching frequency is significantly higher (typically 850 kHz, up to 2.2 MHz), enabling much smaller inductors and capacitors, which helps reduce overall solution size. The integrated synchronous rectification improves efficiency, especially at lower output voltages, and reduces thermal stress on the PCB. However, the maximum continuous output current is limited to 1.2A (with 1.75A peak), which restricts it to lower power applications.
From a layout perspective, the LM2596 requires careful placement of an external inductor, diode, and capacitors, with attention to minimizing loop area to reduce EMI. The LTM8074’s µModule format simplifies layout as most critical components and their parasitic effects are internally optimized; however, the BGA package demands precise assembly and reflow control, and thermal dissipation largely depends on PCB copper and via design underneath the module.
Firmware or control complexity also diverges: the LM2596 is a fixed-frequency device with no internal modes or synchronization, making it simpler to use but less flexible in EMI management or multi-rail sequencing. The LTM8074 offers programmable switching frequency, multiple operating modes (burst, pulse-skipping, spread spectrum), and synchronization pins, allowing the designer to tailor efficiency and noise performance dynamically, which can be critical in noise-sensitive or multi-rail systems.
Cost-wise, the LM2596 is a low-cost, widely available discrete regulator, especially suitable for high-volume, cost-sensitive designs. The LTM8074, being a µModule with integrated components and advanced features, commands a significantly higher unit price and requires more expensive PCB manufacturing and assembly processes due to the BGA package. It is more appropriate when board space, integration, and efficiency under light load are prioritized over raw cost.
Use-case fit
Choose LM2596S-ADJ/NOPB when…
- You need to supply up to 3A continuous current, such as powering a 5V microcontroller rail or logic load with moderate current demands.
- Your design has a relatively generous PCB area, allowing for larger inductors and discrete components.
- Cost constraints dominate, and you can accept a slightly larger BOM and a heat sink on the PCB.
- Your system has a fixed switching frequency and EMI is manageable with standard layout practices.
- You want a regulator with a proven track record and simple implementation without complex control signals.
Choose LTM8074IY#PBF when…
- PCB space is very limited, and minimizing external component size is critical (e.g., dense digital point-of-load converters).
- Your load current requirements are moderate (up to 1.2A continuous) but with occasional peaks to 1.75A.
- You need lower output voltage options down to 0.8V for powering core voltages of FPGAs, CPUs, or SoCs.
- Efficiency at light loads and quiescent current (3 µA typical) is important to extend battery runtime or reduce standby losses.
- You require advanced switching modes, synchronization to an external clock, or soft-start control for power sequencing.
Drop-in compatibility
These parts are not pin-compatible or footprint-compatible. The LM2596S-ADJ/NOPB is a discrete buck regulator IC in a TO-263 (D