TPSM846C24
ZHCSHH6B –JANUARY 2018–REVISED JANUARY 2019
www.ti.com.cn
6.4 Thermal Information
TPSM846C24
MOL (QFN)
59 PINS
8.7
THERMAL METRIC(1)
UNIT
RθJA
ψJT
Junction-to-ambient thermal resistance(2)
Junction-to-top characterization parameter(3)
Junction-to-board characterization parameter(4)
°C/W
°C/W
°C/W
0.9
ψJB
4.3
(1) For more information about 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, 6-layer 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 (section 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 1mm from the device.
6.5 Electrical Characteristics
Over –40°C to 105°C free-air temperature range, VIN = 12 V, VOUT = 1.2 V, IOUT = IOUT(max), ƒSW = 500 kHz,
CIN1 = 4 × 22 µF, 25 V, 1210 ceramic; CIN2 = 2 × 330 µF, 25 V, electrolytic bulk; COUT1 = 4 × 47 µF, 6.3 V, 1210 ceramic;
COUT2 = 2 × 470 µF, 6.3 V, polymer bulk (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
INPUT VOLTAGE (VIN
)
VIN
Input voltage
Over IOUT range
VIN rising
4.5
15
V
V
4.5
4
VIN_UVLO
IVIN
VIN undervoltage lock out
Input operating current
VIN falling
EN = 0 V
7.7
12
mA
OUTPUT VOLTAGE (VOUT
)
VOUT adjustable range(1)
Over IOUT range
0.5
–1%
2
1%
V
RSET = Not loaded, TJ = 25°C, IOUT = 0 A
RSET = 10 kΩ, 1%, TJ = 25°C, IOUT = 0 A(2)
0°C < TJ < 85°C, IOUT = 0 A(1)
Setpoint voltage tolerance
–1.5%
–0.5%
–1%
1.5%
0.5%
1%
VOUT
Temperature variation
–40°C < TJ < 125°C, IOUT = 0 A(1)
Line regulation
4.5 V < VIN < 15 V, IOUT = 0 A
±0.05%
±0.2%
13
Load regulation
Output voltage ripple
Over IOUT range, using remote sense
20-MHz bandwidth
mV
OUTPUT CURRENT
Natural Convection. See SOA graph for derating over
temperature.
Output current
0
35
A
A
IOUT
Overcurrent threshold
Overcurrent accuracy
42
IOC(acc)
ISH(acc)
–15%
–15%
–3
15%
15%
3
(IOUT1 – IOUT2) ÷ ITOTAL, IOUT ≥ 20 A per module(1)
(IOUTx – ITOTAL) ÷ 2, IOUT < 20 A per module(1)
Output current share accuracy
A
SOFT START / STOP
tSStart Internal soft-start time
tSStop Internal soft-stop time
ENABLE (EN)
3
3
ms
ms
Enable high voltage
Enable low voltage
1.3
V
V
Enable threshold voltage
Hysteresis on Enable
VEN
0.8
170
mV
(1) Specified by design.
(2) The stated limit of the set-point tolerance includes the tolernace of both the internal voltage reference and the internal adjustment
resistor. The overall output voltage tolerance is affected by the tolerance of the external RSET resistor.
6
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