PCA9622BS NXP [NXP Semiconductors], PCA9622BS Datasheet - Page 24

• Manufacturer Part Number: PCA9622BS
• Description: 16-bit Fm+ I2C-bus 100 mA 40 V LED driver
• Manufacturer: NXP [NXP Semiconductors]

NXP Semiconductors
PCA9622_3
Product data sheet
10.1.1 Example 1: T
10.1.2 Example 2: T
is known
This example uses a customer’s specific application of the PCA9626B, 24-channel LED
controller in the LQFP48 package, where only the case temperature (T
T
1. Find P
2. Find T
j
R
T
LED output low voltage (LED V
LED output current per channel = 80 mA
Number of outputs = 16
I
V
I
I
R
T
V
I
V
LED output voltage LOW = 0.5 V
LED output current:
I
I
= T
DD(max)
2
2
DD(max)
2
2
amb
case
DD(max)
C-bus clock (SCL) maximum sink current = 25 mA
C-bus data (SDA) maximum sink current = 25 mA
OL
DD(max)
C-bus maximum sink current on clock line = 25 mA
C-bus maximum sink current on data line = 25 mA
th(j-a)
th(j-c)
– output total power = 80 mA
– chip core power consumption = 12 mA
– SCL power dissipation = 25 mA
– SDA power dissipation = 25 mA
P
T
60 mA on 1 port = (60 mA
50 mA on 6 ports = (50 mA
40 mA on 2 ports = (40 mA
20 mA on 12 ports = (20 mA
1 mA on 3 ports = (1 mA
j
tot
case
= (T
of LED ~ 0.5 V
= 50 C
(measured) = 94.6 C
= (320 + 55 + 10 + 10) mW = 708 mW
= 18 C/W
= 83 C/W
+ R
= 12 mA
= 18 mA
j
amb
tot
= 5.5 V
= 5.5 V
(junction temperature):
(device total power dissipation):
th(j-c)
+ R
j
j
calculation of PCA9622DR, in TSSOP32 package, when T
calculation where only T
th(j-a)
P
tot
Rev. 03 — 31 August 2009
, where:
P
tot
) = (50 C + 83 C/W
3)
1)
OL
6)
2)
12)
) = 0.5 V
16
0.4 V = 10 mW
0.4 V = 10 mW
0.5 V = 640 mW
16-bit Fm+ I
case
5.5 V = 66 mW
is known
708 mW) = 108.8 C
2
C-bus 100 mA 40 V LED driver
PCA9622
case
© NXP B.V. 2009. All rights reserved.
) is known.
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amb