HA3994-AL Flyback Transformer for LT3751 | Coilcraft
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Flyback Transformer for
Linear Technology LT3751

  • Developed for Linear Technology LT3751 Capacitor Charger Controller
  • 1500 Vrms, one minute isolation from primary to secondary windings
  • Input: 5 – 24 V; Outputs: 5 V, 3.6 A, +15 V, 1.2 A and −15 V, 1.2 A
  • RoHS-compliant. Tin-silver (96.5/3.5) over tin over nickel over phos bronze terminations


Part number1
Click to get parts
at 0A2
±10% (µH)
at Ipk3
min (µH)
DCR max4
max (µH)
Turns ratio6 Ipk3
typ (Vµsec)
pri : sec1 : sec2 : sec3
HA3994-AL 7.50 6.75 0.018 (pri)
0.020 (sec1)
0.031 (sec2)
0.031 (sec3)
0.22 1 : 0.5 : 1.5 : 1.5 5.0 37.5
1 When ordering, please specify termination code: e.g. HA3994-AL
  Termination: L = RoHS compliant tin-silver over tin over nickel over phos bronze
Special order, added cost: T = RoHS tin-silver-copper (95.5/4/0.5) or
= non-RoHS tin-lead (63/37).
2 Inductance is for the primary, measured at 100 kHz, 0.1 Vrms, 0 Adc using an Agilent/HP 4263B impedance analyzer or equivalent.
3 Ipk: Peak primary current drawn at minimum input voltage.
4 DCR for the primary is with the windings connected in parallel, measured at 25°C. For other operating temperatures, use this DCR at Temperature calculator.
5 Leakage inductance is for both windings of the primary with the secondary windings shorted.
6 Turns ratios are with the primary windings connected in parallel.
7 Ambient temperature range: −40°C to +85°C
8 Storage temperature range: Component: −40°C to +85°C
Packaging trays: −40°C to +80°C
9 Electrical specifications at 25°C.
Refer to Soldering Coilcraft Components before soldering.
PCB washing: Tested to MIL-STD-202 Method 215 plus an additional aqueous wash. More info.

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Updated: April 16, 2018