6.4 Thermal Information
THERMAL METRIC(1) |
LMZ31710 |
UNIT |
RVQ (B3QFN) |
42 PINS |
RθJA |
Junction-to-ambient thermal resistance(2) |
13.3 |
°C/W |
RθJB |
Junction-to-board thermal resistance(3) |
1.6 |
°C/W |
ψJT |
Junction-to-top characterization parameter(4) |
5.3 |
°C/W |
(2) The junction-to-ambient thermal resistance, RθJA, applies to devices soldered directly to a 100 mm × 100 mm double-sided PCB with 2 oz. copper and natural convection cooling. Additional airflow reduces RθJA.
(3) 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.
(4) 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 1 mm from the device.