4

OPERATING LIMITS

The maximum current rating of the CMA1306 depends on the case temperature (Tc) when the LED has reached thermal equilibrium

under steady‑state operation. The graph shown below assumes that the system design employs good thermal management (thermal

interface material and heat sink) and may vary when poor thermal management is employed. Either solder pad shown in the Mechanical

Dimensions section on page 31 can be used as the Tc measurement point.

Another important factor in good thermal management is the temperature of the Light Emitting Surface (LES). Cree recommends a

maximum LES temperature of 140 °C to ensure optimal LED lifetime. Please refer to the Thermal Design section on page 32 for more

information on LES temperature measurement.

CMA1306 - 9 V

0

200

400

600

800

1000

1200

1400

1600

1800

2000

2200

2400

2600

2800

0

25

50

75

100

125

150

Case Temperature (°C)

85 °C, 2400 mA

125 °C,

920 mA

9 V

Standard LEDs

CMA1306 - 9 V eTone

0

200

400

600

800

1000

1200

1400

1600

1800

2000

0

25

50

75

100

125

150

Case Temperature (°C)

85 °C, 1600 mA

9 V

eTone LEDs