4.3 Thermal Information
THERMAL METRIC(1) |
LMZ31520 |
UNIT |
RLG |
72 PINS |
θJA |
Junction-to-ambient thermal resistance(2) |
Natural Convection |
8.6 |
°C/W |
θJA(100LFM) |
Junction-to-ambient thermal resistance(3) |
100 LFM |
7.8 |
°C/W |
ψJT |
Junction-to-top characterization parameter(4) |
1.6 |
°C/W |
ψJB |
Junction-to-board characterization parameter(5) |
4.2 |
°C/W |
(2) The junction-to-ambient thermal resistance, θJA, applies to devices soldered directly to a 100 mm x 100 mm, 6-layer PCB with 1 oz. copper and natural convection cooling. Additional airflow reduces θJA.
(3) The junction-to-ambient thermal resistance, θJA, applies to devices soldered directly to a 100 mm x 100 mm, 6-layer PCB with 1 oz. copper and 100 LFM forced air cooling. Additional airflow reduces θJA.
(4) The junction-to-top characterization parameter, ψJT, estimates the junction temperature, TJ, of a device in a real system, using a procedure described in JESD51-2A (sections 6 and 7). TJ = ψJT * Pdis + TT; where Pdis is the power dissipated in the device and TT is the temperature of the top of the device.
(5) The junction-to-board characterization parameter, ψJB, estimates the junction temperature, TJ, of a device in a real system, using a procedure described in JESD51-2A (sections 6 and 7). TJ = ψJB * Pdis + TB; where Pdis is the power dissipated in the device and TB is the temperature of the board 1mm from the device.