ICS85211AMI-03T IDT, Integrated Device Technology Inc, ICS85211AMI-03T Datasheet - Page 8

• Manufacturer Part Number: ICS85211AMI-03T
• Manufacturer: IDT, Integrated Device Technology Inc

Specifications of ICS85211AMI-03T

• Number Of Outputs: 4
• Operating Supply Voltage (max): 3.465V
• Operating Temp Range: -40C to 85C
• Propagation Delay Time: 1ns
• Operating Supply Voltage (min): 3.135V
• Mounting: Surface Mount
• Pin Count: 8
• Operating Supply Voltage (typ): 3.3V
• Package Type: SOIC N
• Duty Cycle: 53%
• Operating Temperature Classification: Industrial
• Lead Free Status / Rohs Status: Not Compliant

This section provides information on power dissipation and junction temperature for the ICS85211I-03.
Equations and example calculations are also provided.
1. Power Dissipation.
The total power dissipation for the ICS85211I-03 is the sum of the core power plus the power dissipated in the load(s).
The following is the power dissipation for V
NOTE: Please refer to Section 3 for details on calculating power dissipated in the load.
2. Junction Temperature.
Junction temperature, Tj, is the temperature at the junction of the bond wire and bond pad and directly affects the reliability of the
device. The maximum recommended junction temperature for HiPerClockS
In order to calculate junction temperature, the appropriate junction-to-ambient thermal resistance
moderate air flow of 200 linear feet per minute and a multi-layer board, the appropriate value is 103.3°C/W per Table 6 below.
Therefore, Tj for an ambient temperature of 85°C with all outputs switching is:
This calculation is only an example. Tj will obviously vary depending on the number of loaded outputs, supply voltage, air flow,
and the type of board (single layer or multi-layer).
T
85211AMI-03
ABLE
6. T
Single-Layer PCB, JEDEC Standard Test Boards
Multi-Layer PCB, JEDEC Standard Test Boards
NOTE: Most modern PCB designs use multi-layered boards. The data in the second row pertains to most designs.
Power (core)
Power (outputs)
If all outputs are loaded, the total power is 2 * 73.82mW = 147.6mW
Total Power
The equation for Tj is as follows: Tj =
Tj = Junction Temperature
Pd_total = Total Device Power Dissipation (example calculation is in section 1 above)
T
85°C + 0.321W * 103.3°C/W = 118.2°C. This is well below the limit of 125°C.
JA
A
HERMAL
= Ambient Temperature
= Junction-to-Ambient Thermal Resistance
R
ESISTANCE
MAX
_MAX
MAX
= V
= 73.82mW/Loaded Output pair
(3.465V, with all outputs switching) = 173.3mW + 147.6mW = 320.9mW
DD_MAX
JA
* I
FOR
DD_MAX
8-
JA
PIN
P
DD
by Velocity (Linear Feet per Minute)
= 3.465V * 50mA = 173.3mW
= 3.3V + 5% = 3.465V, which gives worst case results.
SOIC, F
OWER
JA
* Pd_total + T
ORCED
C
ONSIDERATIONS
C
ONVECTION
A
8
153.3°C/W
112.7°C/W
D
IFFERENTIAL
0
TM
devices is 125°C.
128.5°C/W
103.3°C/W
-
TO
200
-LVHSTL F
JA
ICS85211I-03
must be used. Assuming a
L
115.5°C/W
OW
97.1°C/W
500
ANOUT
S
REV. B NOVEMBER 14, 2007
KEW
, 1-
B
UFFER
TO
-2