Key Specs
| Spec | Value | Condition | Source |
|---|---|---|---|
| Current Peak Output | - | Digi-Key | |
| Grade | - | Digi-Key | |
| Mounting Type | Surface Mount | Digi-Key | |
| Number Of Channels | 1 | Digi-Key | |
| Operating Temperature Range | -40°C ~ 150°C (TJ) | Digi-Key | |
| Package Case | 8-SOIC (0.154”, 3.90mm Width) | Digi-Key | |
| Propagation Delay Tplh Tphl (Max) | - | Digi-Key | |
| Pulse Width Distortion (Max) | - | Digi-Key | |
| Qualification | - | Digi-Key | |
| Rise Fall Time (Typ) | 10ns, 9ns | Digi-Key | |
| Supplier Device Package | PG-DSO-8-51 | Digi-Key | |
| Technology | Magnetic Coupling | Digi-Key | |
| Voltage Forward Vf (Typ) | - | Digi-Key | |
| Voltage Output Supply | 10V ~ 35V | Digi-Key |
When To Use
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10V–35V input isolated gate drive, single channel: The wide 10V to 35V output supply voltage range matches well with industrial gate drive rails and ensures compatibility with a broad set of MOSFET gate thresholds. Using a synchronous buck controller here risks shoot-through without magnetic isolation, causing gate drive cross-conduction and device failure.
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High-temperature environments up to 150°C TJ: The 1EDI20N12AFXUMA1’s maximum junction temperature rating of 150°C supports operation in harsh environments like automotive or industrial power stages. A typical synchronous buck controller without this thermal margin may enter thermal shutdown prematurely or suffer latch-up under elevated temperatures.
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Fast switching gate drive with rise/fall times ~10ns: The part’s 10ns rise and 9ns fall time ensures crisp MOSFET turn-on and turn-off, minimizing switching losses and reducing gate ringing. Using a slower isolated driver risks excessive switching loss or partial MOSFET conduction, leading to thermal runaway.
When Not To Use
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Output current demand > 20A peak: The current rating is not specified but implied low; this part is disqualified by limited current capacity. Use a multi-phase buck controller that can parallel multiple FETs or channels to meet high current needs.
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Efficiency-critical synchronous buck with external MOSFETs: The internal magnetic coupling and switching characteristics limit efficiency optimization and gate drive flexibility. For maximum efficiency with external FETs, select a high-current synchronous buck with external FETs controller.
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Switching frequency > 500kHz: Rise/fall times and magnetic coupling are optimized for moderate switching speeds. For designs requiring > 500kHz operation to reduce inductor size, use a high-frequency buck controller specialized for fast timing and low jitter.
Application Notes
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The switching node (SW) pin must have low-inductance routing to minimize voltage overshoot caused by fast 10ns rise/fall transitions; keep loop area minimal to reduce EMI and ringing.
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Pins 4 and the typically control and feedback pins pin are noise-sensitive; route them away from the switching node and noisy power traces, and add local bypass capacitors close to these pins to stabilize magnetic coupling operation.
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Guard routing around the magnetic coupling core and sensitive analog pins is recommended to prevent capacitive crosstalk, which can cause erratic propagation delay or pulse width distortion despite the nominal absence of these parameters in the datasheet.
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Ensure the output supply voltage remains within 10V to 35V under all transient conditions; undervoltage or overvoltage can cause unpredictable gate drive levels or driver latch-up.
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Use a solid ground plane under the device to provide a stable reference for magnetic coupling and reduce ground bounce during fast switching transitions.
Gotchas
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[Ignoring derating at high TJ]: The datasheet’s maximum junction temperature of 150°C is absolute; however, magnetic coupling efficiency and timing parameters degrade near this limit, causing erratic switching or increased propagation delay not shown explicitly. Symptom: intermittent MOSFET partial conduction visible on gate waveform with increased device heating. Fix: Measure actual TJ with thermal imaging and keep operating temperature at least 10°C below max rating.
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[SW node layout causing oscillations]: A long or high-inductance trace on the switching node causes high-voltage ringing coupled back into the driver through magnetic coupling, resulting in unstable output pulses. Symptom: jitter and occasional missing pulses on gate drive waveform during load transients. Fix: Minimize SW node loop area and place the device close to the MOSFET gate with low-inductance traces.
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[Startup sequencing with undervoltage]: If the output supply voltage ramps slowly or dips below 10V during startup, the internal magnetic coupling can fail to establish proper gate drive. Symptom: device appears dead or MOSFET never fully turns on, despite correct wiring. Fix: Provide a clean, stable supply above 10V before enabling switching, or add a supervisor circuit.
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[Output capacitor ESR affecting stability]: Low ESR ceramic capacitors on the output supply line can interact with the internal magnetic coupling and cause oscillations or pulse width distortion. Symptom: ringing or oscillations on gate drive waveform at steady state. Fix: Include a small ESR polymer or tantalum capacitor in parallel to damp high-frequency oscillations.