TPS61175: Request for Ultra-Low Quiescent Current Boost Converter Solution for Portable Device

Hi Zaim,

The expert of this device is out of office and will be back next week. The response may be delayed.

Just let me know if it's very urgent.

Regards

Lei

Hi Lei,

Thank you for your prompt response.

I apologize for any confusion in my initial message. I mistakenly mentioned the TPS61175; I intended to refer to the TPS61040, as shown in the attached TINA schematic.

Additionally, I need to correct the power consumption requirement. I am aiming for less than 50µA, not 500µA. My apologies for these errors.

Given the urgency of this matter, any interim suggestions or solutions from TI that you can provide would be greatly appreciated. This component is the final piece needed for us to complete and release our device, so a quick and efficient solution is critical. I would greatly appreciate a quick response due to the urgency of the project.

Having worked with TI components for years, I am very satisfied with their quality and performance. Your recommendations are highly valued.

Thank you for your assistance.

Best regards,
Zaim

Hi Zaim,

I'll check and give you the feedback early next week.

Regards

Lei

Hi Zaim,

Sorry for my late response because I were fully focused on another very urgent case these days. The device is TPS61040, not TPS61175, so I'll support.

Appreciate your recognition on TI components

Here are my comments on your schematic for your reference:

1. In your current schematic, the FB is forced lower than Vref and no feedback control. I just wonder why the Vout is just 400V as you wanted. In my simulation the Vout is far beyond 400V and out of control. As an usual way, I suggested to add feedback control to regulate the node1 to 100V or node2 to 400V;
2. Regarding the charge pump, a charge resistor is recommended to be added in series with each charge capacitor; the capacitances can be a little bigger since in my simulation, the voltage will be more stable;
3. Suggest to add a diode between the NPN base and emit (or gate and source for a MOS). The diode can protect the low side FET in the device better. If there is no this diode, it's not sure where will the major part of the 100V drops, on the NPN or on the low side FET?

Regarding the device, TPS61096A has much lower IQ, and the same topology can be used. Please check whether it's more suitable to your application.

Regards

Lei

Hi Lei,

Thank you for your feedback on my preliminary design using the TPS61040. I appreciate the detailed insights and suggestions you provided.

Given the constraints of my project, I am still facing challenges in achieving the required 400V at 30µA output while maintaining ultra-low power consumption. The TPS61040, although a good example, has a topology that consumes more current than desired for my application. Similarly, while the TPS61096A offers lower IQ, its internal inductor setup may not align well with my design requirements.

Updated Requirements:

• Output Voltage: 400V DC
• Output Current: 30µA
• Input Voltage: 3.3V
• Power Consumption for Boosting: Less than 50µA (ideally around 30µA)

Challenges:

• Achieving the required 400V with minimal quiescent current.
• Ensuring overall power consumption stays within the limits for a portable, battery-powered device.

Request for Alternative Solutions:

Could you recommend another topology or component that would be more suitable for achieving these requirements? Specifically:

1. Efficient Boost Converters: Components or topologies that can efficiently boost 3.3V to 400V with ultra-low power consumption.
2. Charge Pump Configurations: Feasibility and design considerations for using charge pump configurations that align with my low-power consumption needs.
3. Component Alternatives: Any other components, potentially outside the TPS series, that could be better suited for achieving 400V at 30µA with minimal power consumption.

Your guidance in identifying a more efficient solution for this low-power high-voltage requirement would be immensely helpful. I am open to any suggestions, including different topologies or innovative design approaches that can meet the stringent power consumption criteria.

Thank you once again for your assistance.

Best regards,
Zaim

Hi Zaim,

You are welcome. I'm glad that we can provide something helpful.

May I check what's the detailed reasons of TPS61096A's "internal inductor setup" that doesn't align with your design requirements?

A switching node with regulated voltage can be configured to charge pump, so I think TPS61096A can also work.

Thank you.

Regards

Lei