6
LMZ31710
SNVS987F –JULY 2013–REVISED MAY 2020
www.ti.com
Product Folder Links: LMZ31710
Submit Documentation Feedback Copyright © 2013–2020, Texas Instruments Incorporated
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application
report.
(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 TTis
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 TBis
the temperature of the board 1 mm from the device.
6.4 Thermal Information
THERMAL METRIC(1) LMZ31710
UNITRVQ (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
(1) See Light Load Efficiency (LLE) for more information for output voltages < 1.5 V.
(2) The minimum PVIN is 2.95 V or (VOUT + 0.7 V), whichever is greater. See Table 7 for more details.
(3) The maximum PVIN voltage is 17 V or (22 x VOUT), whichever is less. See Table 7 for more details.
(4) The maximum output voltage may be limited by the power dissipation. The maximum power dissipation of this device is 4.5 W.
(5) The stated limit of the set-point voltage tolerance includes the tolerance of both the internal voltage reference and the internal
adjustment resistor. The overall output voltage tolerance will be affected by the tolerance of the external RSET resistor.
6.5 Electrical Characteristics
Over –40°C to 85°C free-air temperature, PVIN = VIN = 12 V, VOUT = 1.8 V, IOUT = 10 A,
CIN = 0.1 µF + 2 × 22 µF ceramic + 100 µF bulk, COUT = 4 × 47 µF ceramic (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
IOUT Output current TA= 85°C, natural convection 0(1) 10 A
VIN Input bias voltage range Over output current range 4.5 17 V
PVIN Input switching voltage range Over output current range 2.95(2) 17(3) V
UVLO VIN undervoltage lockout VIN Increasing 4 4.5 V
VIN Decreasing 3.5 3.85
VOUT(adj) Output voltage adjust range Over output current range 0.6 5.5(4) V
VOUT
Set-point voltage tolerance TA= 25°C, IOUT = 0 A ±1%(5)
Temperature variation –40°C ≤TA≤+85°C, IOUT = 0 A ±0.2%
Line regulation Over input voltage range ±0.1%
Load regulation Over output current range ±0.2%
Total output voltage variation Includes set-point, line, load, and temperature variation ±1.5%(5)
ηEfficiency
PVIN = VIN = 12 V
IO= 5 A
VOUT = 5 V, fSW = 1 MHz 93%
VOUT = 3.3 V, fSW = 750 kHz 92%
VOUT = 2.5 V, fSW = 750 kHz 90%
VOUT = 1.8 V, fSW = 500 kHz 89%
VOUT = 1.2 V, fSW = 300 kHz 86%
VOUT = 0.9 V, fSW = 250 kHz 84%
VOUT = 0.6 V, fSW = 200 kHz 81%
PVIN = VIN = 5 V
IO= 5 A VOUT = 3.3 V, fSW = 750 kHz 94%
VOUT = 2.5 V, fSW = 750 kHz 93%
VOUT = 1.8 V, fSW = 500 kHz 92%
VOUT = 1.2 V, fSW = 300 kHz 89%
VOUT = 0.9 V, fSW = 250 kHz 87%
VOUT = 0.6 V, fSW = 200 kHz 83%
Output voltage ripple 20 MHz bandwidth 14 mVP-P
ILIM Current limit threshold ILIM pin open 15 A
ILIM pin to AGND 12 A