12.1 Layout Guidelines

The I²C signals (SDA / SCL) should be kept away from potential noise sources.

The traces carrying power through the LEDS should be wide enough to the handle necessary current.

All LED current passes through the device and into the ground node. There must be a strong connection between the device ground and the circuit board ground. For the RHB package, the thermal pad should be connected to ground to help dissipate heat.

12.2 Layout Example

Figure 23. PW Layout Example

Figure 24. RHB Layout Example

The thermal relief vias are connected to the power pad of the RHB package shown in Figure 24.

12.3 Thermal Considerations

The maximum IC junction temperature should be restricted to 150°C under normal operating conditions. To calculate the maximum allowable dissipation, PD(max) for a given ambient temperature, use the following equation as a guideline:

Equation 8.

where

• P_D(max) = maximum allowable power dissipation
• T_J(max) = maximum allowable junction temperature (150°C for the TLC59116)
• T_A = ambient temperature of the device
• Θ_JA = junction to air thermal impedance.

See Thermal Information section. This parameter is highly dependent upon board layout.

Power dissipation in the device is determined by the LED current and the voltage at the OUTx pins. For example, if the LED current is 50 mA continuous through each channel and the output voltage is 1 V on each channel, then the total power dissipation is 50 mA x 1 V x 16 ch = 0.8 W