DRV595: The application of DRV595

Lacey Lin

Intellectual 2900 points

Part Number: DRV595

Hi team,

My customer want to use the DRV595 to drive TEC in Atlas system. Please help to answer below question:

1. They has two 5W TEC in the system, the supply voltage is 12V. Can the DRV595 drive two TEC?

2. For the LC filter design in the datasheet

1) What's the ESR requirement of the C1 and C2? Can we use the ceramic capacitor?

2) What's the requirement of the Inductor? Such as the DCR. How to choose the Inductor. Does the switch frequency and the power of TEC decide the chosen of the TEC?

Lacey

Thanks a lot!

over 6 years ago

0 Shawn Zheng over 6 years ago

TI__Mastermind 24835 points

Hi Tracey,
Ceramic caps can be used in the output filter. The beter, the ESR is lower. The cap rated voltage usually should be larger than 1.8*PVCC.
The inductor with higher DCR cost more power and efficiency is lower. So the better, the DRC is lower. Please make sure the rated current is higher than the max output current.
We have a LC filter for audio amp application, I think it should apply to this application. www.ti.com/.../slaa701a.pdf
Best regards,
Shawn Zheng

0 Lacey Lin over 6 years ago in reply to Shawn Zheng

TI__Intellectual 2900 points

Hi Shawn，
Just to confirm one information:
1. In the DRV595, there has two sets output P/N, can anyone set P/N support one 5W Tec with 12V voltage?
2. the current spec ±4A is for one output P/N, or need to connect two sets P/N?
Lacey
Thanks a lot!

0 Shawn Zheng over 6 years ago in reply to Lacey Lin

TI__Mastermind 24835 points

Hi Lacey,
The two OUTP need to be connected together and so are the two OUTN. Please refer to reference design in the Figure 13 in the datasheet. So the amp ony supports one differntial output. All of the data in the datasheet is for this application.
Best regards,
Shawn Zheng

0 Lacey Lin over 6 years ago in reply to Shawn Zheng

TI__Intellectual 2900 points

Hi Shawn,

Thanks so much for your reply!

Customer feedback for the coupling cap in the PVCC, because they can only just use the MLCC cap, so the maximum cap value is 10uF.

So for the application of 5W, can you help to recommend the design for the coupling cap using the maximum 10uF cap?

Lacey

Thanks a lot!

0 Shawn Zheng over 6 years ago in reply to Lacey Lin

TI__Mastermind 24835 points

Hi Lacey,
We usually recommend customers to use larger than 100uF caps for PVCC decoupling - lower value caps cause larger ripple on the power supply. For lower output power application, the caps value can be lower as long as the ripple voltage is accepatable. Please read these app notes for PVCC caps selection: www.ti.com/.../slyt199.pdf
www.ti.com/.../slta055.pdf
Best regards,
Shawn Zheng

0 Lacey Lin over 6 years ago in reply to Shawn Zheng

TI__Intellectual 2900 points

Hi Shawn，
Because of the PCB size limitation, customer consider to parallel two TECs and use the one DRV595.
Does this solution has feasibility?
Lacey
Thanks a lot!

0 Shawn Zheng over 6 years ago in reply to Lacey Lin

TI__Mastermind 24835 points

Hi Lacey,

Basically you could do that, but need to take care of the following points. Please make sure the paralleled load is larger than 1.6Ohm(which is the recommendede min load impedance) and the output current is less than 7.5A to avoid OC FAULT. With lower load impedance, the efficiency is lower. Please pay highly attendtion to the thermal performance during PCB design.

Best regards,

Shawn Zheng

Because of the holidays, TI E2E™ design support forum responses will be delayed from Dec. 25 through Jan. 2. Thank you for your patience.

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DRV595: The application of DRV595