PCA9624 All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2016. All rights reserved.
Product data sheet Rev. 4.1 — 18 January 2016 23 of 40
NXP Semiconductors
PCA9624
8-bit Fm+ I
2
C-bus 100 mA 40 V LED driver
1. Find P
tot
(device total power dissipation)
– output current (60 mA 1 port); output power (60 mA 1 0.5 V) = 30 mW
– output current (50 mA 6 ports); output power (50 mA 6 0.5 V) = 150 mW
– output current (40 mA 1 port); output power (40 mA 1 0.5 V) = 20 mW
Output total power = 200 mW
– chip core power consumption = 10 mA 5.5 V = 55 mW
– SCL power dissipation = 25 mA 0.4 V = 10 mW
– SDA power dissipation = 25 mA 0.4 V = 10 mW
P
tot
(device total power dissipation) = 275 mW
2. Find T
j
(junction temperature):
T
j
= T
case
+ R
th(j-a)
P
tot
= 94.6 C + 30 C/W 275 mW = 102.85 C
11. Limiting values
[1] Each bit must be limited to a maximum of 100 mA and the total package limited to 800 mA due to internal
busing limits. The pull-up (current limiting) resistor must be of sufficient size (W) and value () to guarantee
that the 100 mA limit is not exceeded on any output.
[2] Refer to Section 10.1
for calculation.
Table 14. Limiting values
In accordance with the Absolute Maximum Rating System (IEC 60134).
Symbol Parameter Conditions Min Max Unit
V
DD
supply voltage 0.5 +6.0 V
V
I/O
voltage on an input/output pin V
SS
0.5 5.5 V
V
drv(LED)
LED driver voltage V
SS
0.5 40 V
I
O(LEDn)
output current on pin LEDn - 100 mA
I
OL(tot)
total LOW-level output current LED driver outputs;
V
OL
=0.5V
[1]
800 - mA
I
SS
ground supply current per V
SS
pin - 800 mA
P
tot
total power dissipation T
amb
=25C-1.8W
T
amb
=85C - 0.72 W
P/ch power dissipation per channel T
amb
=25C-100mW
T
amb
=85C-45mW
T
j
junction temperature
[2]
- +125 C
T
stg
storage temperature 65 +150 C
T
amb
ambient temperature operating 40 +85 C
