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BQ27501: Merging solar charger with battery gauges and buck converter

Part Number: BQ27501
Other Parts Discussed in Thread: CC3220SF-LAUNCHXL, BQ24650EVM-639, BQ25570EVM-206, , BQ24650

Hi, I have purchased BQ24650EVM-639, CC3220SF-LAUNCHXL, OPT3001DNPT, and HDC2080DMBT from Digikey.

My team is trying to create an outdoor Wi-Fi ambient tracking application.

I also ordered a 3.5 Watt 6 Volt solar panel. (Open Circuit Voltage: 7.7V, Peak Current: 550mA)

https://www.voltaicsystems.com/3-5-watt-panel

This is the battery, which I bought from Adafruit, I'm trying to charge; Lithium Ion Battery Pack - 3.7V 2200mAh (PRODUCT ID: 1781)

SHENZHEN PKCELL BATTERY CO, Model:ICR18650 2200mAh 3.7V 1S1P

This is the detailed specification

https://cdn-shop.adafruit.com/product-files/1781/C2253_-_ICR18650_2200mAh_3.7V_with_PCM_20140728_APPROVED_8.18.pdf

Compared to BQ25570EVM-206, I need to add a buck converter to supply 1.8V or 3.3V.

Also, I wish to track the remaining battery capacity (mAh), state-of-charge (%), run-time to empty (min.), battery voltage (mV), and temperature (°C) with TI's battery fuel gauges ICs.

Q0. Since BQ27501 is in NRND (Not Recommended for New Designs), what could be an alternative for my case?

Q1. I'm looking for a buck converter from TI that

- 1 regulated output

- adjustable Vout; I will use voltage divider resistor to create 2.9V or 1.8V system power (or fixed 1.8V)

- max current output: 150mA

- don't want ball grid array type of packages

- low power consumption

Can you give a recommendation to me with this, please?

Since the BQ24650 is using the 600-kHz NMOS-NMOS Synchronous Buck Controller, I think the switching frequency might be another issue.

Q2. I'm new with the battery gauge devices from TI. After getting a recommendation, what will be the connection when using

. the solar charger

- buck converter

- battery gauge

?