TMC2100 DATASHEET (Rev. 1.07 / 2017-MAY-15)
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15.3 Thermal Characteristics
The following table shall give an idea on the thermal resistance of the package. The thermal
resistance for a four layer board will provide a good idea on a typical application. Actual thermal
characteristics will depend on the PCB layout, PCB type and PCB size. The thermal resistance will
benefit from thicker CU (inner) layers for spreading heat horizontally within the PCB. Also, air flow will
reduce thermal resistance.
A thermal resistance of 24K/W for a typical board means, that the package is capable of continuously
dissipating 4.1W at an ambient temperature of 25°C with the die temperature staying below 125°C.
Parameter
Symbol Conditions
Typ
Unit
Typical power dissipation
PD
stealthChop or spreadCycle, 0.92A
2.6
W
RMS in two phase motor, sinewave,
40 or 20kHz chopper, 24V, internal
supply, 84°C peak surface of package
(motor QSH4218-035-10-027)
Thermal resistance junction to
ambient on a multilayer board
RTMJA
Dual signal and two internal power
plane board (2s2p) as defined in
JEDEC EIA JESD51-5 and JESD51-7
(FR4, 35µm CU, 84mm x 55mm,
d=1.5mm)
24
21
K/W
K/W
Thermal resistance junction to
ambient on a multilayer board
for TQFP-EP48 package
RTMJA
Dual signal and two internal power
plane board (2s2p) as defined in
JEDEC EIA JESD51-5 and JESD51-7
(FR4, 35µm CU, 70mm x 133mm,
d=1.5mm)
Thermal resistance junction to
board
RTJB
RTJC
PCB temperature measured within
1mm distance to the package
8
3
K/W
K/W
Thermal resistance junction to
case
Junction temperature to heat slug of
package
Table 15.1 Thermal Characteristics QFN5x6 and TQFP-EP48
The thermal resistance in an actual layout can be tested by checking for the heat up caused by the
standby power consumption of the chip. When no motor is attached, all power seen on the power
supply is dissipated within the chip.
Note
A spread-sheet for calculating TMC2100 power dissipation is available on www.trinamic.com.
www.trinamic.com