Schematic for RT9525 ESP32 Wireless BMS: This is ESP32-S3-MINI-1...

Battery Management System Design

flux

1:03

General (prev)

Chat History

Project

Knowledge Base

Using Knowledge Base Tool.

To expand from a single-cell to a multi-cell BMS, you’ll need to:

Choose a multi-cell charger/BMS IC
- Swap out U1 (RT9525) for a dedicated multi-cell monitor/charger such as TI’s BQ76920 (up to 3 cells) or BQ76930 (up to 10 cells).
- These ICs integrate per-cell voltage sensing, over/under-voltage protection, and passive cell balancing.
Add cell-balance circuitry
- Each cell requires a bleed resistor network controlled by the BMS IC to equalize voltages.
- Place balancing MOSFETs or resistors and route individual cell sense lines back to the new BMS IC.
Revise voltage dividers and sense nets
- Replace your single VSYS sense resistor divider ([R3]/[R4]) with an array of dividers for each cell.
- Create separate nets (CELL1, CELL2, …) tied to the IC’s CELLx pins.
Upgrade connectors and insulation
- Use a higher-voltage pack connector rated for the total stack voltage (e.g., 12.6 V for 3 cells).
- Ensure creepage/clearance distances and high-voltage isolation for ESP32 level shifters or use an isolated ADC interface.
Adapt the power-rail architecture
- The TPS62160 input (VSYS) must handle the pack’s full voltage range; check its max VIN (36 V).
- Consider a pre-regulator or a higher-voltage buck if your cell count exceeds its rating.
Update firmware and GPIO assignments
- Map the new BMS status flags (OV, UV, CHG, DSG) to ESP32 GPIOs.
- Implement per-cell voltage monitoring and balancing commands in your firmware.
Layout and thermal considerations
- Based on Flux KB guidance, “when designing single-cell BMS, compare to 2-cell …” you must now prioritize “component placement to minimize high-voltage loop areas” and ensure copper spacing meets the pack’s max voltage.
- Distribute thermal vias under the BMS IC to dissipate balancing heat.
Safety and protection add-ons
- Add input reverse-polarity protection (Schottky or ideal diode) and a TVS array rated to the stack voltage.
- Include an NTC thermistor on each cell group (as supported by many multi-cell BMS ICs).

By following these steps—selecting a multi-cell BMS IC, routing individual cell sense/balance lines, upgrading connectors, and revising power rails—you’ll extend your design to reliably charge, monitor, and balance multiple cells.

128 days

rahmmed

can you change it for me?

128 days

flux

0:59

General (prev)

Chat History

Project

Action

Library

Considering schematic modifications.

Checking if I can make the changes for you.

Starting 1 component search

Searching: "BQ76920"

Completed 1 component search.

Planning schematic modification.

Components to Add

Part Name	Purpose	Manufacturer Part Number	Quantity	Footprint	Datasheet link
BQ7692000PWR	3-cell battery monitor & balancer IC to replace the single-cell RT9525 and manage per-cell sensing and balancing	BQ7692000PWR	1	TSSOP-20	PDF

Components to Remove

U1
(RT9525 single-cell charger IC)

128 days

Ready.

+3V3

Resistance

1.5k Ω

Capacitance

10u F

EN1

VIN

CHRG_EN

+3V3

EN2

Resistance

10k Ω

Resistance

1.5k Ω

VIN

+3V3

IC1

Capacitance

1u F

Capacitance

2.2u F

VBAT

+3V3

Resistance

10k Ω

SYSOFF

Inductance

2.2u H

Capacitance

0.1u F

POWER

BAT

Capacitance

1u F

VSYS

SYSTEM

VSYS

SYSOFF

Capacitance

22u F

EN1

VSYS

EN2

Resistance

1k Ω

Resistance

100k Ω

VBAT

LED2

ESP_EN

VBAT

CHRG_EN

+3V3

LED1

VIN

Capacitance

10u F

VBAT

Reviews

Design Rule Checks

Overlapping Copper

Reports copper elements that are shorting.

Invalid Layer

Reports nodes that are assigned to a layer that doesn't exist in the layout stackup.

Component Overrides • 25

	Designator	Ruleset
	IC1:361d32e4	Override rule for
	IC1:361d32e4	Override rule for
		Override rule for
	＊`REF`＊	Override rule for ＊`REF`＊
	＊`REF`＊	Override rule for ＊`REF`＊
	＊`REF`＊	Override rule for ＊`REF`＊
	＊`REF`＊	Override rule for ＊`REF`＊
	＊`REF`＊	Override rule for ＊`REF`＊
	＊`REF`＊	Override rule for ＊`REF`＊
	＊`REF`＊	Override rule for ＊`REF`＊
	＊`REF`＊	Override rule for ＊`REF`＊
	＊`REF`＊	Override rule for ＊`REF`＊
	＊`REF`＊	Override rule for ＊`REF`＊
	＊`REF`＊	Override rule for ＊`REF`＊
	＊`REF`＊	Override rule for ＊`REF`＊
	＊`REF`＊	Override rule for ＊`REF`＊
	＊`REF`＊	Override rule for ＊`REF`＊
	＊`REF`＊	Override rule for ＊`REF`＊
	＊`REF`＊	Override rule for ＊`REF`＊
	＊`REF`＊	Override rule for ＊`REF`＊
	＊`REF`＊	Override rule for ＊`REF`＊
	＊`REF`＊	Override rule for ＊`REF`＊
	＊`REF`＊	Override rule for ＊`REF`＊
	＊`REF`＊	Override rule for ＊`REF`＊
	＊`REF`＊	Override rule for ＊`REF`＊

Airwires

Reports missing routed traces between pads in a net.

Deprecated Rules

Reports nodes that are using rules that are not supported anymore.

Layers with Multiple Fills

Reports layers that have multiple copper fills of different nets. Make sure the Connected Layers rule value of nets with fills is valid.

Floating Copper

Detect any via, trace or copper fill island that is not connected to any net.

Protected Intrusions • 3

	Protected	Intruder
	Polygon	Trace 4782
	Polygon	Trace c861
	Polygon	Via-6-9

Missing Footprints

Reports parts that have no footprint.

Manufacturing

Manufacturer Part Number • 16

	Designator	MPN
	C1	None
	C2	None
	C3	None
	C4	None
	C5	None
	C6	None
	C7	None
	L1	None
	LED1	None
	LED2	None
	R1	None
	R2	None
	R3	None
	R4	None
	R5	None
	R6	None

Parts Available

Beta

Checks that all parts have a part number and are available from distributors.

System Checks

Auto-Layout

Beta

Reports issues with Auto-Layout if Flux cannot route something or must ignore a configuration.

Passive Components

Resistor Power Rating

Beta

Checks that the power traveling across a given resistor is under its rating with 50% headroom.

Learn more

Pull Up/Pull Down Presence

Beta

Checks that IC pins that require pull up or pull down resistors have them.

Learn more

Capacitor Voltage Rating

Beta

Checks that capacitors have appropriate voltage ratings to prevent overheating and ensure reliable circuit operation.

Ground
A common return path for electric current. Commonly known as ground.
jharwinbarrozo
20.5M
Net Portal
Wirelessly connects nets on schematic. Used to organize schematics and separate functional blocks. To wirelessly connect net portals, give them same designator. #portal
jharwinbarrozo
43.0M
Power Net Portal
Wirelessly connects power nets on schematic. Identical to the net portal, but with a power symbol. Used to organize schematics and separate functional blocks. To wirelessly connect power net portals, give them the same designator. #portal #power
jharwinbarrozo
11.4M
Generic Resistor
A generic fixed resistor for rapid developing circuit topology. Save precious design time by seamlessly add more information to this part (value, footprint, etc.) as it becomes available. Standard resistor values: 1.0Ω 10Ω 100Ω 1.0kΩ 10kΩ 100kΩ 1.0MΩ 1.1Ω 11Ω 110Ω 1.1kΩ 11kΩ 110kΩ 1.1MΩ 1.2Ω 12Ω 120Ω 1.2kΩ 12kΩ 120kΩ 1.2MΩ 1.3Ω 13Ω 130Ω 1.3kΩ 13kΩ 130kΩ 1.3MΩ 1.5Ω 15Ω 150Ω 1.5kΩ 15kΩ 150kΩ 1.5MΩ 1.6Ω 16Ω 160Ω 1.6kΩ 16kΩ 160kΩ 1.6MΩ 1.8Ω 18Ω 180Ω 1.8KΩ 18kΩ 180kΩ 1.8MΩ 2.0Ω 20Ω 200Ω 2.0kΩ 20kΩ 200kΩ 2.0MΩ 2.2Ω 22Ω 220Ω 2.2kΩ 22kΩ 220kΩ 2.2MΩ 2.4Ω 24Ω 240Ω 2.4kΩ 24kΩ 240kΩ 2.4MΩ 2.7Ω 27Ω 270Ω 2.7kΩ 27kΩ 270kΩ 2.7MΩ 3.0Ω 30Ω 300Ω 3.0KΩ 30KΩ 300KΩ 3.0MΩ 3.3Ω 33Ω 330Ω 3.3kΩ 33kΩ 330kΩ 3.3MΩ 3.6Ω 36Ω 360Ω 3.6kΩ 36kΩ 360kΩ 3.6MΩ 3.9Ω 39Ω 390Ω 3.9kΩ 39kΩ 390kΩ 3.9MΩ 4.3Ω 43Ω 430Ω 4.3kΩ 43KΩ 430KΩ 4.3MΩ 4.7Ω 47Ω 470Ω 4.7kΩ 47kΩ 470kΩ 4.7MΩ 5.1Ω 51Ω 510Ω 5.1kΩ 51kΩ 510kΩ 5.1MΩ 5.6Ω 56Ω 560Ω 5.6kΩ 56kΩ 560kΩ 5.6MΩ 6.2Ω 62Ω 620Ω 6.2kΩ 62KΩ 620KΩ 6.2MΩ 6.8Ω 68Ω 680Ω 6.8kΩ 68kΩ 680kΩ 6.8MΩ 7.5Ω 75Ω 750Ω 7.5kΩ 75kΩ 750kΩ 7.5MΩ 8.2Ω 82Ω 820Ω 8.2kΩ 82kΩ 820kΩ 8.2MΩ 9.1Ω 91Ω 910Ω 9.1kΩ 91kΩ 910kΩ 9.1MΩ #generics #CommonPartsLibrary
jharwinbarrozo
1.5M
Generic Capacitor
A generic fixed capacitor ideal for rapid circuit topology development. You can choose between polarized and non-polarized types, its symbol and the footprint will automatically adapt based on your selection. Supported options include standard SMD sizes for ceramic capacitors (e.g., 0402, 0603, 0805), SMD sizes for aluminum electrolytic capacitors, and through-hole footprints for polarized capacitors. Save precious design time by seamlessly add more information to this part (value, footprint, etc.) as it becomes available. Standard capacitor values: 1.0pF 10pF 100pF 1000pF 0.01uF 0.1uF 1.0uF 10uF 100uF 1000uF 10,000uF 1.1pF 11pF 110pF 1100pF 1.2pF 12pF 120pF 1200pF 1.3pF 13pF 130pF 1300pF 1.5pF 15pF 150pF 1500pF 0.015uF 0.15uF 1.5uF 15uF 150uF 1500uF 1.6pF 16pF 160pF 1600pF 1.8pF 18pF 180pF 1800pF 2.0pF 20pF 200pF 2000pF 2.2pF 22pF 20pF 2200pF 0.022uF 0.22uF 2.2uF 22uF 220uF 2200uF 2.4pF 24pF 240pF 2400pF 2.7pF 27pF 270pF 2700pF 3.0pF 30pF 300pF 3000pF 3.3pF 33pF 330pF 3300pF 0.033uF 0.33uF 3.3uF 33uF 330uF 3300uF 3.6pF 36pF 360pF 3600pF 3.9pF 39pF 390pF 3900pF 4.3pF 43pF 430pF 4300pF 4.7pF 47pF 470pF 4700pF 0.047uF 0.47uF 4.7uF 47uF 470uF 4700uF 5.1pF 51pF 510pF 5100pF 5.6pF 56pF 560pF 5600pF 6.2pF 62pF 620pF 6200pF 6.8pF 68pF 680pF 6800pF 0.068uF 0.68uF 6.8uF 68uF 680uF 6800uF 7.5pF 75pF 750pF 7500pF 8.2pF 82pF 820pF 8200pF 9.1pF 91pF 910pF 9100pF #generics #CommonPartsLibrary
jharwinbarrozo
1.5M
Generic Inductor
A generic fixed inductor for rapid developing circuit topology. *You can now change the footprint and 3D model at the top level anytime you want. This is the power of #generics
jharwinbarrozo
15.0k
Terminal
An electrical connector acting as reusable interface to a conductor and creating a point where external circuits can be connected.
natarius
RMCF0805JT47K0
47 kOhms ±5% 0.125W, 1/8W Chip Resistor 0805 (2012 Metric) Automotive AEC-Q200 Thick Film #forLedBlink
jharwinbarrozo
1.2M
875105359001
10uF Capacitor Aluminum Polymer 20% 16V SMD 5x5.3mm #forLedBlink #commonpartslibrary #capacitor #aluminumpolymer #radialcan
jharwinbarrozo
1.2M
CTL1206FYW1T
Yellow 595nm LED Indication - Discrete 1.7V 1206 (3216 Metric) #forLedBlink
jharwinbarrozo
1.1M

Inspect

RT9525 ESP32 Wireless BMS

Controls

Properties

License

https://creativecommons.org/licenses/by/4.0/

Availability & Pricing

Distributor		Qty 1

Assets

Thumbnail

RT9525 ESP32 Wireless BMS image.png

id=RT9525 ESP32 Wireless BMS image

Welcome 👋

Flux helps you build PCBs faster with an AI teammate!

Create your account to collaborate, stay updated, fork your own version, and get instant answers from our AI agent.