Digital adaptive synchronous rectifiers with an integrated power MOS combine the SR controller and rectifier MOSFET in one package — replacing secondary-side Schottky or discrete-SR solutions with minimal external parts for chargers and adapters.
Reading the Key Parameters
- Drain Stress: 40V/60V/80V/100V classes listed; pick by output voltage plus transformer reflected voltage, with margin.
- RDS_ON (integrated MOS): roughly 9mΩ–14mΩ — sets secondary conduction loss directly; go low for high-current outputs.
- Operating modes: CCM/QR/DCM all supported — no pairing constraint with the primary controller's mode.
- Turn-on/off timing: minimum on-time about 0.7–1.0μs, minimum off-time 0.3–2.5μs, turn-on threshold −150/−180mV, pre-off threshold −40/−60mV — these govern false turn-on and early-off behavior at high frequency and light load.
- Package: SOP-8L and DFN 5x6 — the DFN's thermal pad suits higher-current tiers.
Three Steps
- Lock the voltage class (40–100V) from output voltage plus reflected voltage;
- Pick the RDS_ON tier by output current, then check conduction loss and temperature rise;
- Verify minimum on/off times are compatible with the primary controller's narrowest pulse at your switching frequency.
Common Pitfalls
- Choosing voltage class from output voltage alone, missing reflected voltage and ringing spikes;
- Comparing only RDS_ON while ignoring timing thresholds — then hiccuping on false turn-on at light load;
- Using the SOP package at high-current tiers and losing the efficiency gain to heat.
Filter by voltage class and RDS_ON in the online parametric tool; for fit questions, submit a part-number inquiry.