FSL126MR
onsemi FSL126MR (Power Management - AC/DC Offline Regulator/Integrated Power Switch) is suitable for applications such as system regulation, battery charging and power conversion. Guaranteed genuine original; electrical characteristics and pin package are per the official Datasheet. Contact us for pricing, samples and stock availability.
Isometric preview; switch to top or 3D.
DIP-8 · Generic package illustration
Based on the catalogue package field; not verified for this part. Check manufacturer documentation for dimensions, polarity and pinout.View part documentation ↓- Package
- DIP-8
Product overview
onsemi FSL126MR (Power Management - AC/DC Offline Regulator/Integrated Power Switch) is suitable for applications such as system regulation, battery charging and power conversion. Guaranteed genuine original; electrical characteristics and pin package are per the official Datasheet. Contact us for pricing, samples and stock availability.
- Manufacturer
- FSC
- Part number
- FSL126MR
- Category
- AC-DC Offline Regulators / Integrated Power Switches
- Package
- DIP-8
- Condition
- New & Original
- Compliance
- RoHS Compliant
- Lifecycle
- Confirm with manufacturer
- Lead time / MOQ
- Confirm with quotation
Technical parameters
42 parametersConstruction
- FSL126MR −40 to 105°C FSL126MR 8−Lead, Dual Inline Package
- 3000 Units / Tube
- EAS Single Pulsed Avalanche Energy (Note 5)
- 73 mJ
- PD Total Power Dissipation
- 1.5 W
- ESD Human Body Model, JESD22−A114 (Note 6)
- 5 KV
- Charged Device Model, JESD22−C101 (Note 6)
- 2
- CISS Input Capacitance VGS = 0 V, VDS = 25 V, f = 1 MHz
- 210 pF
- COSS Output Capacitance VGS = 0 V, VDS = 25 V, f = 1 MHz
- 33.3 pF
- td(ON) Turn−On Delay VDS = 350 V, IDS = 2
- 23 ns
- tr Rise Time VDS = 350 V, IDS = 2
- 16.4 ns
- td(OFF) Turn−Off Delay VDS = 350 V, IDS = 2
- 17.2 ns
- tf Fall Time VDS = 350 V, IDS = 2
- 23 ns
- fOSC Switching Frequency VDS = 650 V, VGS = 0
- 67 KHz
- fFM Frequency Modulation
- ±3 KHz
- DMAX Maximum Duty Cycle VFB = 4
- 77 %
- DMIN Minimum Duty Cycle VFB = 0
- 0 %
- VSTOP After Turn−On
- 8 V
- tS/S Internal Soft−Start Time VFB = 4
- 15 ms
- VBURL
- 0.45 V
- VBUR(HYS)
- 150 mV
- tOSP Output Short Threshold Time TJ = 25°C
- 1.00 ms
- VOSP Threshold VFB > VOSP and Lasts Longer than
- 1.60 V
Performance
- VSTR VSTR Pin Voltage −
- 50.0 V
- VDS Drain Pin Voltage −
- 50.0 V
- VCC Supply Voltage
- 26 V
- VFB Feedback Voltage Range −
- 12.0 V
- ID Continuous Drain Current
- 2 A
- IDM Drain Current Pulsed (Note 4)
- 8 A
- TA Operating Ambient Temperature
- 105 °C
- TSTG Storage Temperature
- 150 °C
- QJA Junction−to−Ambient Thermal Resistance (Note 7, 8)
- 80 °C/W
- QJC Junction−to−Case Thermal Resistance (Note 7, 9)
- 19 °C/W
- QJT Junction−to−Top Thermal Resistance (Note 7, 10)
- 33.7 °C/W
- BVDSS Drain−Source Breakdown Voltage VCC = 0 V, ID = 250 mA
- 650 V
- IDSS Zero Gate Voltage Drain Current VDS = 650 V, VGS = 0
- 250 mA
- VSTART UVLO Threshold Voltage
- 12 V
- IFB Feedback Source Current VFB = 0
- 400 mA
- VBURH Burst−Mode Voltage VCC = 14 V, VFB Sweep
- 0.60 V
- ILIM Peak Current Limit TJ = 25°C, di/dt = 300 mA/ms
- 1.50 A
- tCLD Current Limit Delay Time (Note 11)
- 200 ns
- VSD Shutdown Feedback Voltage VCC = 15
- 6.0 V
- IDELAY Shutdown Delay Current VFB = 5
- 5.0 mA
- VOVP Over−Voltage Protection Threshold VFB = 2
- 24.0 V
Specifications & documentation
Use the official manufacturer documentation to verify electrical characteristics, package dimensions and operating limits before design approval.
Frequently asked questions
Common pre-quotation questions and selection notes to help you verify key parameters and sourcing before requesting a quote.
What is a drop-in replacement for FSL126MR?
FSL126MR is a DIP-8 LDO, fixed-output, up to low-current. Pin-compatible families include LM1117 / NCP1117 / LD1117 (same SOT-223 or TO-252 footprint). Match dropout voltage and the output-capacitor ESR rule before swapping.
LDO or DC-DC — which should I use?
Use an LDO for low-current, noise-sensitive rails (analog / RF, small ΔV). Use a DC-DC (buck) when the input-output voltage gap is large or efficiency / battery life matters. A common hybrid: DC-DC first, then LDO to clean the rail.
What output capacitor ESR does it require?
Legacy 1117-class LDOs need output-cap ESR between 0.3 Ω and 22 Ω; all-ceramic caps (very low ESR) can oscillate — add a 1–3 Ω series resistor or a small electrolytic. Modern LDOs are stable with low-ESR MLCCs.
How do I verify the part is genuine / avoid counterfeit?
Buy only from authorized or franchised channels. On receipt, check: (1) laser-etched markings that solvent will not remove; (2) batch / lot code consistent between label and device; (3) original reel or tube packaging; (4) request traceability documents (CoC, date code). For critical parts, third-party X-ray / decapsulation testing is recommended.
How do I read the markings / date code on a chip?
Most active ICs use a 4-digit date code YYWW (year + week, e.g. 2345 = 2023 week 45). The top mark is manufacturer logo + base part number + lot code. For SMD code lookup, search by "marking code + package" on AllDataSheet / Octopart / LCSC.
What does the package code mean (TO-220, SOT-23, QFP…)?
Package codes describe the physical form factor and pin layout — critical when sourcing, because electrically equivalent parts in different packages will not fit the PCB. Common: TO-220 (3-terminal power), SOT-23 (3-pin small signal), DIP / SOIC (through-hole / SMD ICs), QFP / QFN (MCUs, processors).
What if my original model is discontinued (EOL / NRND)?
Three options: (1) the manufacturer’s recommended replacement; (2) franchised distributor legacy stock; (3) a functionally compatible cross-brand part — provided pinout and key parameters match. Always evaluate on a real board before mass swap.
What is the minimum order quantity (MOQ) and lead time?
We support both sample and volume orders. Minimum order quantity, stock availability and lead time are confirmed per inquiry — tell us your model and quantity and we will quote. Sample quantities for design validation are supported.
Can I get the datasheet and samples?
The full datasheet is linked on this page. For parts without a direct datasheet, we can locate the manufacturer document on request. Sample requests are supported — contact us with your model and quantity.
Request confirmation of current stock, date code, packaging, price and delivery terms. Product information does not constitute a binding offer; final specifications are confirmed with your quotation.