AD8142-EVALZ Просмотр технического описания (PDF) - Analog Devices

Номер в каталоге

Компоненты Описание

производитель

AD8142-EVALZ

Low Cost, Triple Differential Drivers for Wideband Video

Analog Devices 

ABSOLUTE MAXIMUM RATINGS

Table 2.

Parameter

Supply Voltage

HSYNC, VSYNC, SYNC LEVEL

Power Dissipation

Input Common-Mode Voltage

Storage Temperature Range

Operating Temperature Range

Lead Temperature (Soldering 10 sec)

Junction Temperature

Rating

5.5 V

VS−/VS+

See Figure 3

VS−/VS+

−65°C to +125°C

−40°C to +85°C

300°C

150°C

Stresses above those listed under Absolute Maximum Ratings

may cause permanent damage to the device. This is a stress

rating only; functional operation of the device at these or any

other conditions above those indicated in the operational

section of this specification is not implied. Exposure to absolute

maximum rating conditions for extended periods may affect

device reliability.

THERMAL RESISTANCE

θJA is specified for the worst-case conditions, that is, θJA is

specified for the device soldered in a circuit board in still air.

Table 3. Thermal Resistance with the Underside Pad

Thermally Connected to a Copper Plane

Package Type/PCB Type

θJA

θJC

Unit

24-Lead LFCSP/4-Layer

38 4.7 °C/W

MAXIMUM POWER DISSIPATION

The maximum safe power dissipation in the AD8141/AD8142

package is limited by the associated rise in junction temperature

(TJ) on the die. At approximately 150°C, which is the glass

transition temperature, the plastic changes its properties. Even

temporarily exceeding this temperature limit can change the

stresses that the package exerts on the die, permanently shifting

the parametric performance of the AD8141/AD8142. Exceeding

a junction temperature of 175°C for an extended period can result

in changes in the silicon devices potentially causing failure.

AD8141/AD8142

The power dissipated in the package (PD) is the sum of the

quiescent power dissipation and the power dissipated in the

package due to the load drive for all outputs. The quiescent

power is the voltage between the supply pins (VS) times the

quiescent current (IS). The load current consists of differential and

common-mode currents flowing to the loads, as well as currents

flowing through the internal differential and common-mode

feedback loops. The internal resistor tap used in the common-

mode feedback loop places a 12.5 kΩ differential load on the

output. RMS output voltages should be considered when

dealing with ac signals.

Airflow reduces θJA. In addition, more metal directly in contact

with the package leads from metal traces, through holes, ground,

and power planes reduce the θJA. The exposed pad on the underside

of the package must be soldered to a pad on the PCB surface that is

thermally connected to a PCB plane to achieve the specified θJA.

Figure 3 shows the maximum safe power dissipation in the

package vs. the ambient temperature for the 24-lead LFCSP

(38°C/W) on a JEDEC standard 4-layer board with the underside

paddle soldered to a pad that is thermally connected to a PCB

plane. θJA values are approximations.

6

5

4

3

2

1

0

–40

–20

0

20

40

60

80

AMBIENT TEMPERATURE (°C)

Figure 3. Maximum Power Dissipation vs. Temperature for a 4-Layer Board

ESD CAUTION

Rev. 0 | Page 5 of 24

Share Link: