NEED INFORMATION- OPA454AIDDAG4

Hi Jayakumara,

Thank you for your inquiry.

For #5 and #7, I am afraid it will take two weeks to answer.

1. Junction Temperature Max (Tj Max)  130 [C]

 2. Typical Power dissipation (Pd typ)

    We assume that supply voltage=+/-50V, Iq=+/-3.2mA, Rout=4.8kohm,  on spec sheet.

 a) power for Iq

     (+50v-(-50v)) x 3.4mA = 320mW

 b) power of output

    ( 50V - 48V ) x 10mA = 20mW

 a) + b) = 340 mW

3. Maximum Power dissipation (Pd max)

 Please note power dissipation can not exceed value restricted by package thermal resistance and ambient temperature as follows.

 ThetaJA [C/W] x Pd(MAX) [W] + Ta [C] < Tj(MAX) [C]

 If in condition of land area of 1-inch x 1-inch, 2-oz copper, Theta JA = 24[C/W] (from specsheet page 5.)

     24 [C/W] x Pd(MAX) [W] + 85 [C] < 130(MAX) [C]

     Pd(MAX) < 1.875 [W]

 If in condition of exposed-pad sized area of 1-oz copper, Theta JA = 52[C/W] (from specsheet page 5.)

     52 [C/W] x Pd(MAX) [W] + 85 [C] < 130(MAX) [C]

     Pd(MAX) < 0.865[W]

4. Thermal Resistance Junction to Ambient (Theta JA)  24 [C/W] / 52 [C/W] (from specsheet page 5.)

5. Thermal Resistance Junction to Board (Theta JB)

6. Thermal Resistance Junction to Case (Theta JC) 10 [C/W]

7. Weight [gram]

Best regards,

 Ichiro Itoi

Hi Jayakumara,

Here are answers for remaining questions.

4. Thermal Resistance Junction to Ambient (Theta JA): 38.7 [C/W] by simulation

5. Thermal Resistance Junction to Board (Theta JB): 20.5 [C/W] by simulation

6. Thermal Resistance Junction to Case (Theta JC): 47.1 [C/W](top) by simulation, 0.7 [C/W](bottom) by simulation

7. Weight: 81.7 [mg]

      http://focus.ti.com/quality/docs/searchbyopn.tsp?templateId=5909&navigationId=11220&orderablePartNo=OPA454AIDDAG4&pnType=A

Best regards,

Ichiro itoi