Key Specs

SpecValueConditionSource
TypeFor DC/DC Converters[Digi-Key]
ApplicationsIsolated Buck Converters[Digi-Key]
Intended ChipsetMAX253, MAX845, MAX3535, MXL1535[Digi-Key]
Chipset ManufacturerAnalog Devices, Inc[Digi-Key]
Voltage Primary-[Digi-Key]
Voltage Auxiliary-[Digi-Key]
Voltage Isolation1500Vrms[Digi-Key]
Inductance Frequency-[Digi-Key]
Frequency-[Digi-Key]
Operating Temperature Range-40°C ~ 85°C[Digi-Key]
Grade-[Digi-Key]
Qualification-[Digi-Key]
Mounting TypeSurface Mount[Digi-Key]
Size Dimension0.320” L x 0.280” W (8.13mm x 7.11mm)[Digi-Key]
Height Seated (Max)0.200” (5.08mm)[Digi-Key]
Footprint-[Digi-Key]
Style-[Digi-Key]

When To Use

The TGM-240NSLFTR is best suited for isolated buck converter applications where a high level of isolation and efficiency are crucial. Some examples include:

In these scenarios, the TGM-240NSLFTR’s 1500Vrms isolation voltage and high switching frequency make it an excellent choice.

When Not To Use

  1. Buck regulator outputting over 3A continuous: The maximum 0.8 Ω DCR and unspecified current rating limit power handling and cause excessive conduction loss at higher currents. Use a high-current synchronous buck with external FETs for efficient high-current operation and thermal management.

  2. High-frequency switching > 500 kHz for miniaturized magnetics: The unspecified inductance frequency and maximum switching frequency of 11 V-μs suggest this part is not optimized for high-frequency operation. Use a high-frequency buck controller designed for stable operation above 500 kHz with low core loss magnetics.

  3. Battery-powered sensor requiring ultra-low quiescent current: The part’s spec and typical application do not address low-IQ operation needed for μA-level sleep currents. Use a low-IQ PFM buck regulator to prevent premature battery depletion.


Application Notes

When designing with the TGM-240NSLFTR, keep in mind the following application notes:

Gotchas

  1. Incorrect selection of capacitor (Cin):
    • What the engineer does: Selects a capacitor with insufficient voltage rating.
    • What actually happens: Premature failure due to excessive voltage across the capacitor, leading to a short circuit.
    • How to fix or avoid it: Ensure that the selected capacitor has a higher voltage rating than the primary voltage and consider using multiple capacitors in parallel for added safety.
  2. Inadequate thermal management:
    • What the engineer does: Fails to account for heat dissipation during operation.
    • What actually happens: Excessive temperature buildup, leading to reduced component lifespan or even catastrophic failure.
    • How to fix or avoid it: Ensure proper heatsink installation and consider using a high-temperature-rated package or thermal interface material.