Alternatives to onsemi UC3843AN
onsemi UC3843AN and its qualified second sources, compared on form/fit/function, stock, lifecycle and price — the same checks Parter runs inside a BOM.
 UC3843ANonsemi | UC3843ANTexas Instruments |  UC3843BNGonsemi | +2more | |
|---|---|---|---|---|
| FFF Compatibility | Both parts share the identical standard 8-pin PDIP pinout and land pattern.Both parts use the standard 8-pin plastic dual-in-line package (PDIP-8) with identical body dimensions and spacing.The TI UC3843AN matches the original onsemi UC3843AN in all major electrical parameters, including startup thresholds (8.4V/7.6V) and 100% duty cycle capability. | Both parts share the identical standard 8-pin PDIP pinout.Both parts use the standard PDIP-8 package with equivalent mechanical layout.It performs the identical switching controller function with compatible electrical characteristics and the same temperature range (0°C to 70°C). | ||
 AI Summary | UC3843AN by onsemi: Boost, Flyback Regulator Positive, Isolation Capable Output Step-Up, Step-Up/Step-Down DC-DC Controller IC 8-PDIP. | The Texas Instruments UC3843AN is an active, direct drop-in replacement that retains the identical part number and performance characteristics of the obsolete onsemi device. It features the same low-startup current and precise duty cycle control.
| This is onsemi's official active replacement in the same series, transitioning the design to the newer 'B' revision. It offers equivalent logic, duty cycle, and voltage ratings but uses a slightly modified silicon layout.
| |
| Lifecycle Status | Obsolete | Active | Active | |
| Market Availability | Discontinued | In stock | In stock | |
| REACH | REACH | REACH | REACH | |
| RoHS | RoHS | RoHS | RoHS | |
| Description | Boost, Flyback Regulator Positive, Isolation Capable Output Step-Up, Step-Up/Step-Down DC-DC Controller IC 8-PDIP | Regulator Output DC-DC Controller IC 8-PDIP | Boost, Flyback Regulator Positive, Isolation Capable Output Step-Up, Step-Up/Step-Down DC-DC Controller IC 8-PDIP | |
| Manufacturer | onsemi | Texas Instruments | onsemi | |
| Type | Power Management (PMIC) | Power Management (PMIC) | Power Management (PMIC) | |
| Datasheet | Open | Open | Open | |
| Lead Time | Unknown | 9 weeks | 18 weeks | |
| Country of Origin | - | - | - | |
| Export Control Class Number | EAR99 | EAR99 | EAR99 | |
| HTSUS Code | 8542.39.0070 | - | - | |
| Moisture Sensitivity Level | 1 (Unlimited) | - | - | |
| Function | Step-Up, Step-Up/Step-Down | - | - | |
| Topology | Boost, Flyback | - | - | |
| Clock Sync | No | - | - | |
| Output Type | Transistor Driver | - | - | |
| Mounting Type | Through Hole | - | - | |
| Output Phases | 1 | - | - | |
| Package / Case | 8-DIP (0.300", 7.62mm) | - | - | |
| Control Features | Frequency Control | - | - |
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Frequently asked questions
Yes. The onsemi UC3843AN 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 UC3843AN are the UC3843AN (Texas Instruments) and the UC3843BNG (onsemi), out of 4 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 UC3843AN 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 UC3843AN (onsemi) is a part in the Power Management (PMIC) category. This page lists qualified, cross-referenced replacements for it with a side-by-side comparison.
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