PCU9655PW,518 NXP Semiconductors, PCU9655PW,518 Datasheet - Page 24

• Manufacturer Part Number: PCU9655PW,518
• Description: LED Lighting Drivers 16-ch Ufm 5 MHz bus 40 V LED Driver
• Manufacturer: NXP Semiconductors

Specifications of PCU9655PW,518

• Rohs: yes
• Input Voltage: 3 V to 5.5 V
• Maximum Supply Current: 16 mA
• Mounting Style: SMD/SMT
• Package / Case: TSSOP-28
• Power Dissipation: 1.54 W
• Factory Pack Quantity: 2500

NXP Semiconductors
PCU9655
Product data sheet
10.1 Thermal considerations
Since the PCU9655 device integrates 16 voltage switches, thermal considerations should
be taken into account to prevent overheating, which can cause the device to go into
thermal shutdown.
In order to ensure that the device will not go into thermal shutdown when operating under
certain application conditions, its junction temperature (T
that is below the overtemperature threshold limit (125 C). The T
on the ambient temperature (T
resistance.
The device junction temperature can be calculated by using the following equation:
where:
An example of this calculation is show below:
Conditions:
P
T
This confirms that the junction temperature is below the minimum overtemperature
threshold of 125 C, which ensures the device will not go into thermal shutdown under
these conditions.
T
j
tot
j
T
T
R
P
T
R
I
I
V
P
IC_power = (I
IC_power = (0.012 A  5 V) = 0.06 W
LED drivers_power = 16  (I
LED drivers_power = 16  ((0.1 A)
P
T
T
calculation:
LED
DD(max)
=
j
amb
amb
j
j
tot
DD
tot
tot
th(j-a)
th(j-a)
calculation:
= junction temperature
= T
= 50 C + (65 C/W  0.86 W) = 105.9 C
T
= (device) total power dissipation
= IC_power + LED drivers_power;
= 0.06 W + 0.8 W = 0.86 W
= 100 mA / channel
= 5 V
amb
= ambient temperature
= 50 C
amb
= junction to ambient thermal resistance
= 65 C/W (per JEDEC 51 standard for multilayer PCB)
= 12 mA
+
+ R
R
th j-a
th(j-a)

DD
All information provided in this document is subject to legal disclaimers.

 V

 P
P
DD
tot
Rev. 2 — 2 October 2012
tot
)
LED
amb
2
), device’s total power dissipation (P
16-channel UFm 5 MHz bus 100 mA 40 V LED driver
 R
2
 5 ) = 0.8 W
on
)
j
) should be calculated to ensure
j
of the device depends
PCU9655
tot
© NXP B.V. 2012. All rights reserved.
), and thermal
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