ON Semi Rectifier Selection: MURA110T3G vs MURS360BT3G vs MBRS3200T3G — Ultrafast vs Schottky | ICMASS

MURA110T3G vs MURS360BT3G vs MBRS3200T3G: Full Comparison

Ultrafast vs Schottky: The Fundamental Trade-off

These three parts represent two technologies with opposite strengths.

Ultrafast diodes (MURA110, MURS360) are P-N junction devices. They store charge during conduction that must be swept out at turn-off — that's the t_rr spec. The benefit: ultra-low reverse leakage (microamps). The cost: measurable switching loss at high frequency.

Schottky diodes (MBRS3200) are metal-semiconductor junction devices. No stored charge = zero recovery loss. The benefit: low V_F and clean switching. The cost: reverse leakage in the milliamp range that doubles with every 20–25°C rise in junction temperature.

The decision tree is simple. Ask three questions in order:

1. What's your rail voltage? >150V → ultrafast only (Schottky tops out at 200V, and you need margin).
2. What's your ambient temperature? >85°C and blocking >100V → ultrafast (Schottky leakage runs away).
3. What's your switching frequency? >200kHz → lean Schottky (zero recovery saves more watts as frequency rises).

When to Choose MURA110T3G (Low-Voltage Ultrafast)

The MURA110T3G is optimised for one thing: the fastest possible recovery at low voltage. At 30ns t_rr and 100V rating, it's the right call for:

• 12V/24V DC-DC converters below 200kHz. The 30ns recovery is the fastest of the three parts. At 100kHz, reverse recovery loss is negligible (0.3% of the period).
• RCD snubber and clamp circuits. Fast turn-off means the diode stops conducting before the next switching cycle. The SMA package fits in the tight space next to the snubber resistor and capacitor.
• Designs where every penny counts. At $0.02–$0.12/unit, the MURA110T3G is the most cost-effective option for sub-100V rails. If your BOM has 6–8 rectifiers per board, the savings add up.
• 1A circuits that don't need 3A headroom. Don't pay for current you won't use. The MURA110T3G's 1A rating (2A peak) covers the vast majority of auxiliary supplies, gate-drive bias rails, and signal-isolation circuits.

Skip it if: your rail exceeds 75V DC (need more margin), you need >1A continuous, or you're above 500kHz switching frequency.

When to Choose MURS360BT3G (High-Voltage Ultrafast)

The MURS360BT3G is the high-voltage workhorse. 600V, 3A, 75ns — it covers applications the other two can't touch:

• 230V AC SMPS output rectification. Rectified 230V AC gives a ~325V DC bus. With reflected voltage and leakage spikes, the secondary-side rectifier sees 450–550V. The MURS360's 600V rating handles this. The MURA110 (100V) and MBRS3200 (200V) don't come close.
• PFC boost diode (sub-300W). At 400V output, the MURS360 provides 200V of margin. The 75ns t_rr is manageable below 150kHz. For higher power or frequency, move to SiC.
• High-temperature, high-voltage blocking. At 125°C and 600V reverse, the MURS360's leakage is ~150µA. The MBRS3200 at 125°C and 200V leaks 50–100mA — a 500× difference. For hot, high-voltage designs, ultrafast is the only option.
• SMB footprint for compact AC adapters. The SMB package is thinner than SMC and much smaller than TO-220. For 65–90W laptop adapters where board height is at a premium, this matters.

Skip it if: your rail is below 200V (the MURS320T3G gives you 25ns and 0.875V V_F for less money), or if you're on a 48V rail at moderate temperature (the MBRS3200 Schottky is more efficient).

When to Choose MBRS3200T3G (Schottky)

The MBRS3200T3G is the efficiency specialist. 840mV V_F and zero recovery give you the lowest conduction and switching loss of the three — with an important temperature constraint:

• 24V/48V DC-DC output rectification at moderate temperature. At 65°C ambient and 48V DC bus, the MBRS3200T3G is the most efficient of the three. The 840mV V_F saves a full watt of dissipation vs the MURS360 at 3A.
• OR-ing diodes and reverse-polarity protection. Low, tightly-specified V_F gives better current sharing between parallel supplies. The 200V rating handles 24V truck load-dump transients with margin.
• EMI-sensitive designs. No stored charge = no reverse recovery spike. If your board keeps failing radiated emissions at the switch-node frequency, swapping an ultrafast for a Schottky often fixes it without adding a snubber.
• Paralleling for higher current. Schottkys have a positive V_F tempco — the hotter diode's V_F rises, shifting current to the cooler diode. Natural load balancing. No external resistors needed. Two MBRS3200T3G in parallel handle ~5–5.5A.

Skip it if: ambient exceeds 85°C (leakage runs away), rail exceeds 150V (too close to the 200V limit), or you're rectifying line-voltage AC (use MURS360).

What About Pricing and Availability?

Contact ICMASS for a same-day quote on any of these parts. All three are active ON Semi catalog products. We stock the full MURA, MURS, and MBRS series in SMA, SMB, and SMC packages. One shipment from Shenzhen, global DHL/FedEx delivery in 5–10 business days.

Frequently Asked Questions

Q1: Can I use one part number across my entire design?

A: Usually not, and that's by design. A single rectifier family doesn't cover every position efficiently. Your PFC boost diode (400V, high frequency) needs a MURS360. Your 12V bias supply output (low voltage, low current) is better served by a MURA110. Your 48V OR-ing diode wants the MBRS3200's low V_F. Using one part everywhere means you're either over-spending, under-protecting, or both.

Q2: How do I decide between MURA110 and MURS360 when both are ultrafast?

A: Rail voltage and current. MURA110 = ≤75V DC rails, ≤1A. MURS360 = >75V DC rails, up to 3A. On a 48V rail at 1A, the MURA110 gives you faster recovery (30ns vs 75ns) in a smaller package. On a 325V DC bus, the MURA110 isn't even in the conversation — 100V rating vs 325V bus = instant failure.

Q3: Why not just use Schottky everywhere?

A: Temperature and voltage kill Schottkys. Above 85°C ambient while blocking >100V, leakage current runs away. At 125°C junction, the MBRS3200 leaks 50–100mA at 200V — that's 10–20W of pure heat. An ultrafast at the same condition leaks 150µA (30mW). And Schottkys max out at 200V. For 230V AC rectification (~325V DC), there is no Schottky option — you need ultrafast or SiC.

Q4: Do I need heatsinks for any of these?

A: MURA110: almost never. MURS360: maybe. MBRS3200: depends on temperature. The MURA110 at 875mW is trivial — the SMA package handles it with minimal copper. The MURS360 at 3.75W needs a 10×10mm cathode pour; at 85°C ambient, use the SMC version. The MBRS3200 at 2.5W conduction is fine — but if leakage hits 100mA at 125°C (20W), you get thermal runaway. Keep T_J below 100°C.

Q5: What if I need automotive qualification?

A: All three have AEC-Q101 variants. MURA110 → SURA8110T3G. MURS360 → SURS8360BT3G. MBRS3200 → NRVBS3200NT3G. Same silicon, same packages, full PPAP documentation. The standard parts are tested to the same AEC-Q101 standard (the datasheets show it); the variants add the formal paperwork trail.

Q6: Which one has the best EMI performance?

A: MBRS3200T3G (Schottky), by a wide margin. Ultrafast diodes generate a reverse recovery current spike when they turn off — a pulse of current in the reverse direction lasting t_rr nanoseconds. This spike rings with PCB trace inductance and radiates. The MBRS3200T3G has no stored charge, so there's no recovery spike. If your switch-node waveform shows 50MHz+ ringing that won't snub out, try the Schottky.

Related Products

• MURA110T3G — 100V/1A Ultrafast, 30ns, SMA
• MURS360BT3G — 600V/3A Ultrafast, 75ns, SMB
• MBRS3200T3G — 200V/3A Schottky, 840mV, SMB
• MURS320T3G — 200V/3A Ultrafast, 25ns, SMC — faster ultrafast for mid-voltage
• MURS340T3G — 400V/3A Ultrafast, 50ns, SMC — middle ground
• MBRS3100T3G — 100V/3A Schottky, lower V_F for 12–24V rails