The SIT2596S-5.0 from 芯力特 (SIT) is a 3 A step-down (buck) switching voltage regulator that delivers a fixed 5.0 V output. It ships in a TO-263-5 (D2PAK / DD-PAK) surface-mount package and is widely used as a pin-to-pin, function-compatible drop-in for the industry-standard LM2596S-5.0 from Texas Instruments. Jingteng Electronics stocks both the SIT2596S-5.0 and the TI LM2596 family as an independent distributor — we are not an authorized agent of either manufacturer.
What the part is
A 2596-class buck regulator takes a higher DC input and switches it down to a regulated output with high efficiency. For the SIT2596 class the typical specifications are: input voltage around 4.5 V to 40 V, output current up to 3 A, fixed output options of 3.3 V / 5.0 V / 12 V plus an adjustable version, and a switching frequency near 150 kHz. Treat these as class-typical figures and verify the exact numbers on the SIT2596 datasheet for your specific part and temperature grade.
TO-263-5 package, decoded
TO-263-5 is the 5-lead surface-mount version of the D2PAK (also called DD-PAK). The five pins are typically: 1 – Input (VIN), 2 – Output (VOUT / switch node), 3 – Ground (GND), 4 – Feedback (FB, used on the adjustable version), and 5 – ON/OFF (shutdown). The large metal tab is the thermal drain/ground and must be soldered to a generous copper pour on the PCB to move heat away — at 3 A this is not optional. For through-hole boards, the same regulator is offered in TO-220-5.
Pin-to-pin with LM2596S-5.0
Because the SIT2596S-5.0 follows the LM2596 pin map, it drops into existing LM2596S-5.0 layouts. The two parts share the VIN / Output / GND / FB / ON-OFF assignments, so a board designed for TI's LM2596S-5.0 can usually accept the SIT part without re-spinning the footprint. That said, a cross-reference is a compatibility starting point, not a 100% equivalence promise — confirm the pinout, thermal and electrical parameters on both datasheets before committing to production. If you prefer the original TI device, we also carry the TI LM2596S-5.0 and the TI LM2596S-ADJ.
Selection guide: which version do you need?
Fixed 5.0 V vs adjustable: choose the -5.0 when your rail is exactly 5.0 V and you want the simplest BOM (no feedback divider). Choose -ADJ when you need a non-standard voltage or want to trim the output. The SIT2596 family also covers 3.3 V and 12 V fixed outputs for common secondary rails.
Package: TO-263-5 (SMD) for automated assembly and compact boards; TO-220-5 for hand-solderable or heatsink-mounted through-hole designs.
Input / output margin: keep the input comfortably above the output plus the regulator dropout, and size the output capacitor and inductor for your load transient. A 150 kHz switcher is forgiving on inductor size but still needs a correct saturation-current rating.
Thermal and layout notes for 3 A
At 3 A the regulator dissipates real power, especially with a large input-to-output step. Give the TO-263-5 tab a wide, low-impedance copper pour (ideally with thermal vias to an inner ground plane), place the input and output ceramics close to the pins, keep the switch-node loop small, and use a Schottky catch diode rated for the full load current. Skimping on copper is the most common cause of thermal shutdown in 2596-class designs.
Where it fits
SIT2596S-5.0 is a workhorse for 12 V- or 24 V-fed boards that need a clean 5 V rail: industrial controllers, sensor nodes, comms modules, LED drivers and embedded systems. It is a good choice when you want LM2596-class performance with a second-source option.
If you are qualifying a second source or need both the SIT and TI parts side by side, the SIT2596S-5.0 (in stock) we keep in stock is the natural starting point, and we can quote the TI LM2596S-5.0 / LM2596S-ADJ alongside it.
Alternative & Cross-Reference Parts (for reference)
The devices below are commonly used industry parts in the same functional class. They are listed for identification and compatibility-engineering reference only. A cross-reference is not a guarantee of pin-to-pin or 100% functional equivalence — package, pinout, electrical parameters and temperature rating can differ between devices and between manufacturers. Always verify against the original manufacturer's datasheet before substituting any part in a design.
| Manufacturer | Typical part(s) | Class / note |
|---|---|---|
| 芯力特 (SIT) | SIT2596S-5.0 | 3A buck, fixed 5.0 V, TO-263-5 (this part) |
| 芯力特 (SIT) | SIT2596S-3.3 | 3A buck, fixed 3.3 V, TO-263-5 |
| 芯力特 (SIT) | SIT2596S-12 | 3A buck, fixed 12 V, TO-263-5 |
| 芯力特 (SIT) | SIT2596S-ADJ | 3A buck, adjustable output, TO-263-5 |
| Texas Instruments | LM2596S-5.0 | Industry reference, pin-to-pin (TI®) |
| Texas Instruments | LM2596S-3.3 / LM2596S-12 / LM2596S-ADJ | TI® LM2596 family, fixed & adjustable |
SIT (芯力特) is a trademark of its respective owner. Texas Instruments® and LM2596® are trademarks of Texas Instruments Incorporated. Mentioned part numbers are provided for identification and compatibility-engineering purposes only. Jingteng Electronics is an independent distributor and is not affiliated with, authorized by, or an agent of SIT (芯力特) or Texas Instruments.
Related In-Stock Voltage Regulators
| Part number | |
|---|---|
| SIT2596S-5.0 (in stock) | Check stock & quote |
| TI LM2596S-5.0 | Check stock & quote |
| TI LM2596S-ADJ | Check stock & quote |
Frequently Asked Questions
Is SIT2596S-5.0 a drop-in replacement for LM2596S-5.0?
It is designed as a pin-to-pin, function-compatible device in the same TO-263-5 package and is widely used as a drop-in for the LM2596S-5.0 (Texas Instruments). Because cross-references are never a 100% equivalence guarantee, confirm the pinout, electrical parameters and the original SIT2596 and LM2596 datasheets before substituting in a production design.
What does the '-5.0' and 'TO-263-5' mean?
'-5.0' indicates a fixed 5.0 V output; the SIT2596 family also ships as 3.3 V, 12 V and adjustable (-ADJ) versions. 'TO-263-5' is the 5-lead surface-mount D2PAK / DD-PAK package (also called DDPAK); the same die is offered in TO-220-5 for through-hole boards.
How much current can it deliver and what is the input range?
It is a 3 A step-down (buck) switching regulator. For this regulator class the typical input range is about 4.5 V to 40 V and the switching frequency is around 150 kHz, but always verify the exact limits on the SIT2596 datasheet for your part and temperature grade.
What external parts does a SIT2596 design need?
A minimal buck application needs an input capacitor, an output capacitor, a power inductor, a catch (freewheeling) Schottky diode and (for the adjustable version) a two-resistor feedback divider. Fixed-output versions such as the -5.0 do not need the divider but still need the inductor, diode and capacitors.
Can Jingteng supply SIT2596 and the TI LM2596 family?
As an independent distributor we stock the SIT2596S-5.0 as well as the TI LM2596S-5.0 and LM2596S-ADJ. Availability, pricing and date code are confirmed at quotation; for hard-to-find or end-of-life voltages ask early so we can source through verified channels.
Recommended next steps
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Trademark & Cross-Reference Notice
SIT (芯力特) is a trademark of its respective owner; Texas Instruments® and LM2596® are trademarks of Texas Instruments Incorporated. References on this page to SIT or TI part numbers, and any comparison between them, are provided for identification and compatibility-engineering purposes only, indicating the function, package and parametric class a given part belongs to. Jingteng Electronics (Shenzhen Jingteng Electronics Technology Co., Ltd.) is an independent distributor, not an authorized agent or affiliate of SIT (芯力特) or Texas Instruments. A cross-reference does not imply pin-to-pin or 100% functional equivalence; before substituting any device, verify the package, pinout, electrical parameters and the original datasheet. Product availability, pricing and date code are confirmed at quotation.
About Jingteng Electronics
Jingteng Electronics (Shenzhen Jingteng Electronics Technology Co., Ltd.) is an independent distributor of electronic components, focused on hard-to-find and obsolete ICs, analog and power-management devices. We source through long-verified, traceable channels and support BOM matching, small-lot sampling and volume inquiries. Contact us for a quote, or upload your BOM for a consolidated quote.
