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HCPL-316J Datasheet, PDF (30/33 Pages) AVAGO TECHNOLOGIES LIMITED – 2.5 Amp Gate Drive Optocoupler with Integrated (VCE) Desaturation Detection and Fault Status Feedback | |||
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As an example, the total input and output power dis-
sipation can be calculated given the following condi-
tions:
â â¢â ION, MAX ~ 2.0 A
â â¢â VCC2 = 18 V
â â¢â VEE = -5 V
â â¢â fCARRIER = 15 kHz
Step 1: Calculate RG minimum from IOL peak specification:
To find the peak charging lOL assume that the gate is
initially charged the steadyâstate value of VEE. Therefore
apply the following relationship:
RG  =[âVOâH@â65â0 âµAââ â(VOâL+âVEâE)]
ââââââ IOL,PEAK
ââ â   = [âVCâC2 ââ 1ââ â(VOâL â+ VâEEâ)]
ââââââ IOL,PEAK
  = 1â8 Vâââ1 âV ââ(1â.5âV +â(ââ5 Vâ))
âââââ 2.0 A
= 10.25 W
â 10.5 W (for a 1% resistor)
(Note from Figure 76 that the real value of IOL may vary from the value
calculated from the simple model shown.)
Step 2: Calculate total power dissipation in the HCPL-316J:
The HCPLâ316J total power dissipation (PT) is equal to
the sum of the inputâside power (PI) and outputâside
power (PO):
PT = PI + PO
PI = ICC1 * VCC1
PO = PO(BIAS) + PO,SWTICH
âââ = ICC2 * (VCC2âVEE ) + ESWITCH * fSWITCH
where,
MAX. ION, IOFF vs. GATE RESISTANCE
(VCC2 / VEE2 = 25 V / 5 V
4
3
2
1
IOFF (MAX.)
0
-1
ION (MAX.)
-2
-3
0 20 40 60 80 100 120 140 160 180 200
Rg (â¦)
Figure 76. Typical peak ION and IOFF currents vs. Rg (for
HCPL-316J output driving an IGBT rated at 600 V/100 A.
HCPL-316J fig 76
30
PO(BIAS) = steadyâstate power dissipation in the HC-
PLâ316J due to biasing the device.
PO(SWITCH) = transient power dissipation in the HC-
PLâ316J due to charging and discharging power device
gate.
ESWITCH = Average Energy dissipated in HCPLâ316J due
to switching of the power device over one switching
cycle (µJ/cycle).
fSWITCH = average carrier signal frequency.
For RG = 10.5, the value read from Figure 77 is ESWITCH
= 6.05 µJ. Assume a worstâcase average ICC1 = 16.5 mA
(which is given by the average of ICC1H and ICC1L ). Simi-
larly the average ICC2 = 5.5 mA.
PI = 16.5 mA * 5.5 V = 90.8 mW
PO = PO(BIAS) + PO,SWITCH
= 5.5 mA * (18 V â (â5 V)) + 6.051 µJ * 15 kHz
= 126.5 mW + 90.8 mW
= 217.3 mW
Step 3: Compare the calculated power dissipation with the abso-
lute maximum values for the HCPL-316J:
For the example,
PI = 90.8 mW < 150 mW (abs. max.) ) OK
PO = 217.3 mW < 600 mW (abs. max.) ) OK
Therefore, the power dissipation absolute maximum
rating has not been exceeded for the example.
Please refer to the following Thermal Model section for
an explanation on how to calculate the maximum junc-
tion temperature of the HCPLâ316J for a given PC board
layout configuration.
SWITCHING ENERGY vs. GATE RESISTANCE
(VCC2 / VEE2 = 25 V / 5 V
9
8
7
6
5
Ess (Qg = 650 nC)
4
3
2
1
0
0
50
100
150
200
Rg (â¦)
Figure 77. Switching energy plot for calculating average Pswitch
(for HCPL-316J output driving an IGBT rated at 600 V/100 A).
HCPL-316J fig 77
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