Calculation steps

⚠ Warning: The resistor R1 is below the recommended 75 Ohm safety value. If the R1 resistance is below this value an overcurrent in the output stage can occur if the supply voltage is very high (e.g. 20V – 40V). A small resistance could be used if high voltage can be avoided in the application. For further details see the power shift Application Note Ch. 4.

Output parameters (schematic)

PV(max) = ( TJ(max) - TA ) / RthJA
PV(max) = ( 0 °C - 0 °C ) / 0 Ω
PV(max) = 0 W
RSET = ( VIN_SET / IOUT ) ⋅ k0 (use k2 if IOUT > 0 mA, otherwise use k1)
RSET = ( 0 V / 0 mA ) ⋅ 0
RSET = 0 kΩ
R1 = 0 Ω (calculation steps described here)
R2 = 0 Ω (calculation steps described here)

Output parameters (summary)

Result = OK
Description = OK
CFG Setting = GND (GND if IOUT > 0 mA, otherwise open)
Output CFG = OUTH (OUTH if IOUT > 0 mA, otherwise OUTL)
PR1(max) = max { PR10,  ...  , PR120 } = PR10 = 0 W
PR2(max) = max { PR20,  ...  , PR220 } = PR20 = 0 W
PTLD1114(max) = max { PTLD11140,  ...  , PTLD111420 } = PTLD11140 = 0 W
IOUT(max) = max { IOUT0,  ...  , IOUT20 } = IOUT0 = 0 mA

Calculated parameters used in the calculation

Supply Voltage interpolation table

In the next steps the system behavior is calculated at multiple supply voltage levels between VS(min) & VS(max) and for different maximum power shift currents. The calculation searches the optimized resistances R1 and R2 for the power shift feature. This is done by allowing the maximum power dissipation in the TLD1114 device to be as close as possible to PV(max) to exploit the full thermal capability of the TLD1114 LED driver and thus reducing the external component effort. Additionally a crosscheck of the result is done to see whether the target current can be driven under the given application conditions (e.g. temperature and voltages) without overheating. In the next steps the system behavior is calculated at multiple supply voltage levels between VS(min) & VS(max) and for different maximum power shift currents. The calculation searches the optimized resistance R1 for the power shift feature. This is done by allowing the maximum power dissipation in the TLD1114 device to be as close as possible to PV(max) to exploit the full thermal capability of the TLD1114 LED driver and thus reducing the external component effort. Additionally a crosscheck of the result is done to see whether the target current can be driven under the given application conditions (e.g. temperature and voltages) without overheating.
VS interpolation range = [ max{ VS(min),  VOUT + VPS_CC },  VS(max) ]
VS interpolation range = [ max{ 0 V,  0 V + 0 V },  0 V ]
VS interpolation range = [ 0 V,  0 V ]
VSn = max{ VS(min),  VOUT + VPS_CC } + ( ( VS(max) - max{ VS(min),  VOUT + VPS_CC } ) / 20 ) ⋅ n
For the next calculation steps either the proposed values for R1 & R2 (calculation steps described here) or the user defined values are taken into account. For the next calculation steps either the proposed value for R1 (calculation steps described here) or the used defined value is taken into account.
IPSn = ( VSn - VOUT ) / R1
IPSn = 0 mA (1: if VSn - VOUT < VGS(typ))
IPSn = min{ ( VSn - VOUT - VGS(typ) ) / R2,  ( VSn - VOUT ) / ( R1 + R2 + RDSON ) } (2: otherwise if VSn - VOUT < VGS_PWR_SH)
IPSn = min{ ( VGS_PWR_SH - VGS(typ) ) / R2,  ( VSn - VOUT ) / ( R1 + R2 + RDSON ) } (3: otherwise)
IOUTSn = max{ 0 mA,  IOUT - IPSn }
IOUTn = IPSn + IOUTSn
PTLD1114n = ( VSn - VOUT - RSHUNT ⋅ IOUTn ) ⋅ IOUTSn + RSHUNT ⋅ (IOUTn)2
PR1n = R1 ⋅ (IPSn)2
PR2n = R2 ⋅ (IPSn)2
VSn = max{ 0 V,  0 V + 0 V } + ( ( 0 V - max{ 0 V,  0 V + 0 V } ) / 20 ) ⋅ n = 0 V
For the next calculation steps either the proposed values for R1 & R2 (calculation steps described here) or the user defined values are taken into account. For the next calculation steps either the proposed value for R1 (calculation steps described here) or the used defined value is taken into account.
IPSn = ( 0 V - 0 V ) / 0 Ω = 0 mA
IPSn = 0 mA (1)
IPSn = min{ ( 0 V - 0 V - 0 V ) / 0 Ω,  ( 0 V - 0 V ) / ( 0 Ω + 0 Ω + 0 Ω ) } = 0 mA(2)
IPSn = min{ ( 0 V - 0 V ) / 0 Ω,  ( 0 V - 0 V ) / ( 0 Ω + 0 Ω + 0 Ω ) } = 0 mA (3)
IOUTSn = max{ 0 mA,  0 mA - 0 mA } = 0 mA
IOUTn = 0 mA + 0 mA = 0 mA
PTLD1114n = ( 0 V - 0 V - 0 Ω ⋅ 0 mA ) ⋅ 0 mA + 0 Ω ⋅ (0 A)2 = 0 W
PR1n = 0 Ω ⋅ (0 A)2 = 0 W
PR2n = 0 Ω ⋅ (0 A)2 = 0 W

Input parameters used in the calculation

VS(min) = 0 V
VS(max) = 0 V
TA = 0 °C
RthJA = 0 Ω
VOVERHEAD = 0 V
R1 = 0 Ω
RDSON = 0 Ω
VGS(typ) = 0 V
R2 = 0 Ω
VOUT = 0 V
IOUT = 0 mA

Product parameters used in the calculation

TJ(max) = 0 °C
VIN_SET = 0 V
k0 = 0
VPS_CC = 0 V
VGS_PWR_SH = 0 V
RSHUNT = 0 Ω (0.75 Ω  if IOUT > 0 mA, otherwise 1.5 Ω)
PV(max) = ( TJ(max) - TA ) / RthJA
PV(max) = ( 0 °C - 0 °C ) / 0 Ω
PV(max) = 0 W
RSET = ( VIN_SET / IOUT ) ⋅ k0
RSET = ( 0 V / 0 mA ) ⋅ 0
RSET = 0 kΩ
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