PCA9624PW NXP Semiconductors, PCA9624PW Datasheet - Page 21

• Manufacturer Part Number: PCA9624PW
• Description: IC, LED DRIVER, RGBA, 24-TSSOP
• Manufacturer: NXP Semiconductors

Specifications of PCA9624PW

• No. Of Outputs: 8
• Output Current: 100mA
• Output Voltage: 40V
• Input Voltage: 2.3V To 5.5V
• Dimming Control Type: PWM
• Driver Case Style: TSSOP
• Switching Frequency: 1MHz
• Base Number: 9624
• Operating: RoHS Compliant
• Led Driver Application: RGB Or RGBA LED Drivers, LED Status Information, Displays, Backlights
• Rohs Compliant: Yes

NXP Semiconductors
1.
PCA9624_2
Product data sheet
50 C is a typical temperature inside an enclosed system. The designers should feel free, as needed, to perform their own
calculation using the examples.
10.1 Junction temperature calculation
T
T
A device junction temperature can be calculated when the ambient temperature or the
case temperature is known.
When the ambient temperature is known, the junction temperature is calculated using
Equation 4
power dissipation.
where:
When the case temperature is known, the junction temperature is calculated using
Equation 5
dissipation.
where:
Here are two examples regarding how to calculate the junction temperature using junction
to case and junction to ambient thermal resistance. In the first example
given the operating condition and the junction to ambient thermal resistance, the junction
temperature of PCA9624PW, in the TSSOP24 package, is calculated for a system
operating condition in 50 C
(Section
case temperature is known, applying the junction to case thermal resistance equation, the
junction temperature of the PCA9626B, in the LQFP48 package, is calculated.
j
j
T
T
R
P
T
T
R
P
=
=
j
amb
j
case
tot
tot
th(j-a)
th(j-c)
= junction temperature
= junction temperature
T
T
= (device) total power dissipation
= (device) total power dissipation
amb
case
= ambient temperature
= case temperature
= junction to case thermal resistance
= junction to ambient thermal resistance
10.1.2), based on a specific customer application requirement where only the
+
+
and the ambient temperature, junction to ambient thermal resistance and
and the case temperature, junction to case thermal resistance and power
R
R
th j-a
th j-c
P
P
Rev. 02 — 26 August 2009
tot
tot
1
ambient temperature. In the second example
8-bit Fm+ I
2
C-bus 100 mA 40 V LED driver
PCA9624
© NXP B.V. 2009. All rights reserved.
(Section
10.1.1),
21 of 37
(4)
(5)