參數(shù)資料
型號: DS99144
英文描述: QUAD DIFFERENTIAL DRIVERS
中文描述: 四差分驅(qū)動器
文件頁數(shù): 13/16頁
文件大?。?/td> 255K
代理商: DS99144
Agere Systems Inc.
13
Data Sheet
January 1999
BDG1A, BDP1A, BDGLA, BPNGA, BPNPA, and
Quad Differential Drivers
Power Dissipation
System designers incorporating Agere data transmis-
sion drivers in their applications should be aware of
package and thermal information associated with these
components.
Proper thermal management is essential to the long-
term reliability of any plastic encapsulated integrated
circuit. Thermal management is especially important
for surface-mount devices, given the increasing circuit
pack density and resulting higher thermal density. A
key aspect of thermal management involves the junc-
tion temperature (silicon temperature) of the integrated
circuit.
Several factors contribute to the resulting junction tem-
perature of an integrated circuit:
I
Ambient use temperature
I
Device power dissipation
I
Component placement on the board
I
Thermal properties of the board
I
Thermal impedance of the package
Thermal impedance of the package is referred to as
Θ
ja
and is measured in
°
C rise in junction temperature
per watt of power dissipation. Thermal impedance is
also a function of airflow present in system application.
The following equation can be used to estimate the
junction temperature of any device:
T
j
= T
A
+
P
D
Θ
ja
where:
T
j
is device junction temperature (
°
C).
T
A
is ambient temperature (
°
C).
P
D
is power dissipation (W).
Θ
ja
is package thermal impedance (junction to ambi-
ent
°
C/W).
The power dissipation estimate is derived from two fac-
tors:
I
Internal device power
I
Power associated with output terminations
Multiplying I
CC
times V
CC
provides an estimate of inter-
nal power dissipation.
The power dissipated in the output is a function of the:
I
Termination scheme on the outputs
I
Termination resistors
I
Duty cycle of the output
Package thermal impedance depends on:
I
Airflow
I
Package type (e.g., DIP, SOIC, SOIC/NB)
The junction temperature can be calculated using the
previous equation, after power dissipation levels and
package thermal impedances are known.
Figure 10 illustrates the thermal impedance estimates
for the various package types as a function of airflow.
This figure shows that package thermal impedance is
higher for the narrow-body SOIC package. Particular
attention should, therefore, be paid to the thermal man-
agement issues when using this package type.
In general, system designers should attempt to main-
tain junction temperature below 125
°
C. The following
factors should be used to determine if specific data
transmission drivers in particular package types meet
the system reliability objectives:
I
System ambient temperature
I
Power dissipation
I
Package type
I
Airflow
12-2753F
Figure 10. Power Dissipation
DIP
SOIC/NB
J-LEAD SOIC/GULL WING
AIRFLOW (ft./min.)
200
400
600
800
1000
1200
0
40
50
60
70
80
90
100
110
120
130
140
T
Θ
j
(
°
C
相關(guān)PDF資料
PDF描述
DSB2810 SCHOTTKY BARRIER DIODES
DSB5712 SCHOTTKY BARRIER DIODES
DSC Double-Sided Chip Resistors
DSC2512-10DT18 Double-Sided Chip Resistors
DSC2512-10FT18 Double-Sided Chip Resistors
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
DS99R101 制造商:NSC 制造商全稱:National Semiconductor 功能描述:3-40MHz DC-Balanced 24-Bit LVDS Serializer and Deserializer
DS99R101VS 制造商:NSC 制造商全稱:National Semiconductor 功能描述:3-40MHz DC-Balanced 24-Bit LVDS Serializer and Deserializer
DS99R101VS/NOPB 功能描述:LVDS 接口集成電路 RoHS:否 制造商:Texas Instruments 激勵器數(shù)量:4 接收機數(shù)量:4 數(shù)據(jù)速率:155.5 Mbps 工作電源電壓:5 V 最大功率耗散:1025 mW 最大工作溫度:+ 85 C 封裝 / 箱體:SOIC-16 Narrow 封裝:Reel
DS99R101VSX 制造商:NSC 制造商全稱:National Semiconductor 功能描述:3-40MHz DC-Balanced 24-Bit LVDS Serializer and Deserializer
DS99R101VSX/NOPB 功能描述:LVDS 接口集成電路 RoHS:否 制造商:Texas Instruments 激勵器數(shù)量:4 接收機數(shù)量:4 數(shù)據(jù)速率:155.5 Mbps 工作電源電壓:5 V 最大功率耗散:1025 mW 最大工作溫度:+ 85 C 封裝 / 箱體:SOIC-16 Narrow 封裝:Reel