8. Select “standard” resistor values:
Standard 5% Tolerance Resistors
HPWT-
MHOO
Design
Current
Voltage
Category 2
Voltage
Category 3
Voltage
Voltage
Voltage
Category 4 Category 5 Category 6
Flux, F
Flux, G
Flux, H
Flux, J
Flux, K
33.6 mA
29 mA
100 ohm
120 ohm
150 ohm
220 ohm
270 ohm
91 ohm
110 ohm
150 ohm
200 ohm
270 ohm
82 ohm
110 ohm
130 ohm
180 ohm
240 ohm
75 ohm
100 ohm
120 ohm
180 ohm
240 ohm
68 ohm
91 ohm
110 ohm
160 ohm
220 ohm
25 mA
19 mA[1]
15 mA[1]
Note 1: Operation at dc drive currents below 20 mA can cause noticeable light output differences within
the LED array.
9. Group “standard” adjacent cells in resistor matrix in Step 8 as desired:
Standard 5% Tolerance Resistors
HPWT-
MHOO
Design
Current
Voltage
Category 2
Voltage
Category 3
Voltage
Voltage
Voltage
Category 4 Category 5 Category 6
Flux, F
Flux, G
Flux, H
Flux, J
Flux, K
33.6 mA
29 mA
100 ohm
82 ohm
110 ohm
130 ohm
180 ohm
240 ohm
120 ohm
150 ohm
220 ohm
270 ohm
25 mA
19 mA[1]
15 mA[1]
Note 1: Operation at dc drive currents below 20 mA can cause noticeable light output differences within
the LED array.
10. Perform “worst-case” analysis to ensure
that maximum forward current is not exceeded
over temperature.
varies slightly over temperature as shown in
Equation #3.6. This thermal effect can be
included in Equation #3.12 as shown below:
Calculate maximum forward current (using
Equation #3.12) at “worst-case” conditions—
i.e. maximum input voltage, minimum resistor
values, and minimum forward voltages for each
SuperFlux LED emitter forward voltage
category. The forward voltage of LED emitters
EMC Transient Protection
Circuits designed for the automotive electrical
environment must be able to operate over a
wide range of input voltages and be able to
tolerate a number of different types of electrical
transients. These worst-case voltage ranges and
electrical transients have been characterized and
27
LUMILEDS [ LUMILEDS LIGHTING COMPANY ]
