Alternatives to onsemi SN74LS123N
onsemi SN74LS123N and its qualified second sources, compared on form/fit/function, stock, lifecycle and price — the same checks Parter runs inside a BOM.
| SN74LS123Nonsemi |  SN74LS123NTexas Instruments | CD74HCT123ETexas Instruments | +1more | |
|---|---|---|---|---|
| FFF Compatibility | Same PDIP-16 footprint and standard 16-pin assignments matching the original onsemi part.Matches the physical dimensions, pitch, and through-hole mounting style of the standard PDIP-16 package.Fully compatible LS-TTL technology, matching all electrical parameters (supply voltage, output current, timing, and logical behavior). | Identical pinout and DIP-16 package style allowing a direct physical fit.Standard 16-pin PDIP package with identical lead pitch and package width.HCT-CMOS technology provides TTL-compatible input levels, but differences in CMOS timing equations and Rext/Cext component limits may require minor adjustments to external timing components. | ||
 AI Summary | SN74LS123N by onsemi: Monostable Multivibrator. | Texas Instruments' active SN74LS123N is a direct, drop-in replacement that shares the same LS-TTL logic family, supply voltage, and timing characteristics as the obsolete onsemi device.
| The CD74HCT123E provides a high-speed CMOS alternative with TTL-compatible inputs, dramatically reducing quiescent current while retaining the same physical layout.
| |
| Lifecycle Status | Obsolete | Active | Active | |
| Market Availability | Discontinued | In stock | In stock | |
| REACH | Unknown | REACH | REACH | |
| RoHS | Unknown | RoHS | RoHS | |
| Description | Monostable Multivibrator | Monostable Multivibrator 28 ns 16-PDIP | Monostable Multivibrator 25 ns 16-PDIP | |
| Manufacturer | onsemi | Texas Instruments | Texas Instruments | |
| Type | Monostable Multivibrator | Logic | Logic | |
| Datasheet | Open | Open | Open | |
| Lead Time | Unknown | 16 weeks | 9 weeks | |
| Country of Origin | - | - | - | |
| Export Control Class Number | EAR99 | EAR99 | EAR99 | |
| HTSUS Code | - | - | - | |
| Moisture Sensitivity Level | - | - | - |
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Related parts
| Part | Market availability | Lifecycle | Alternatives available |
|---|---|---|---|
 SN74LS13NTexas Instruments | Discontinued | Obsolete | 3Alternatives availableSee Alternatives |
| SN74LS123Donsemi | Discontinued | Obsolete | 5Alternatives availableSee Alternatives |
 SN74LS138NTexas Instruments | In stock | Active | 5Alternatives availableSee Alternatives |
 SN74LS240Nonsemi | In stock | Obsolete | 4Alternatives availableSee Alternatives |
 SN74LS374Nonsemi | In stock | Obsolete | 5Alternatives availableSee Alternatives |
 SN74LS161ANonsemi | In stock | Obsolete | 4Alternatives availableSee Alternatives |
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Frequently asked questions
Yes. The onsemi SN74LS123N is marked obsolete, so the manufacturer has discontinued it and any remaining supply is limited to distributor stock. The qualified second sources on this page are active parts you can design in today.
The closest qualified second sources for the onsemi SN74LS123N are the SN74LS123N (Texas Instruments) and the CD74HCT123E (Texas Instruments), out of 3 matched alternatives in total. Each is compared against the original on fit, form and function in the table above.
Not always. The alternatives to the SN74LS123N are matched on function but can differ in package, pinout or a key parameter, so review the fit/form/function notes in the table and the datasheet before designing one in.
The SN74LS123N (onsemi) is a part in the Monostable Multivibrator category. This page lists qualified, cross-referenced replacements for it with a side-by-side comparison.
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