Schematic for IoT Smartwatch

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1.62 to 5.5V

tonylin

1.62 to 5.5V

Vled: 3.3V

tonylin

Vdd: 1.8V

tonylin

Vled: 3.3V

verify battery charging circuit and recommend any needed changes, how would i wi...

tonylin

@copilot verify battery charging circuit and recommend any needed changes, how would i wire the battery to power the peripherals? also integrate the battery boost tps61221 to power the oled display

copilot

To verify your battery charging circuit and integrate the TPS61221 boost converter for powering the OLED display, we'll first review the critical components and nets related to charging and power distribution. Your project includes the BQ24095DGQR for charging management and a TPS61221DCKR boost converter to elevate the battery voltage for peripherals requiring higher voltages.

Battery Charging Circuit Review

Battery Charging IC (IC3 - BQ24095DGQR): Connected to the battery (BT1), USB port (J1), and various passive components (R9, R10, D1) for charging control.
Battery (BT1 - VL-2330_HFN): Connected via net 18d31f0397240630c649f04d09580c08 for charging and net a4496bdc8124362bce8f45f6cb920116 for grounding.
Charge Status & Power Good (D1 & IC3’s ~PG pin): D1 connected to IC3's ~PG pin indicates charging status.

Recommendations & Integration Steps

Ensure Proper Feedback Network for BQ24095DGQR: The BQ24095DGQR should have a proper feedback network, including ISET to adjust charge current and PRETERM to set the charge termination threshold. Check:
- Connect R9 between J1:VBUS and IC3:IN for input supply. Already connected via Net 18d31f0397240630c649f04d09580c08.
- Ensure R10 between BT1:(+) and IC3:OUT sets the charge current suitably. Already connected via 18d31f0397240630c649f04d09580c08.
- Make sure R8 is properly setting the PRETERM charge termination condition via Net 48ebe8ea3929186fec02b93205705eff.
Integrating TPS61221DCKR Boost Converter:
- Input (VIN) Connection: Connect U2:VIN to BT1:(+), allowing the battery to directly supply the TPS61221. Since the VL-2330 is a lithium coin cell, ensuring its voltage matches the TPS61221's recommended operating range is essential.
- Output (VOUT) Connection: Connect U2:VOUT directly to the OLED1:(5V), providing it with the boosted voltage.
- Ground Connection: Ensure U2:GND is connected to the system ground, which looks to be managed via the various GND nets. Based on your schematic, ensuring a single connected ground network between BT1:(-), IC3:VSS_1, IC3:VSS_2, and U2:GND is necessary.
- Feedback and Enable Pins: The feedback (FB) pin of U2 naturally connects to an internal voltage divider. You don't need to connect it externally unless you're adjusting the output voltage away from the default. For simplicity, leaving FB as is should be fine. Connect U2:EN to a GPIO on IC1 if you want software control over the boost converter or tie it to VIN for always-on operation.
- Inductor and Capacitor: The TPS61221 requires an external inductor connected to U2:L and capacitors on both input and output for stable operation. Often, a value around 2.2µH for the inductor and 10µF for both input and output capacitors is a good start, adjusted based on your specific requirements and the TPS61221 datasheet recommendations.

Example Connections for TPS61221 Integration

Connect U2:VIN to BT1:+.
Connect U2:GND to BT1:-, IC3:VSS_1, and IC3:VSS_2.
Connect U2:VOUT to OLED1:5V.
Optional: Connect U2:EN to IC1 GPIO (for software control) or directly to BT1:+ for always-on.

Conclusion

Your charging circuit appears correctly configured for the BQ24095DGQR functionalities, with charging indication provided by D1 and proper feedback set by resistors. Integrating the TPS61221 requires direct connections to the battery for input and to the OLED for output, respecting ground coherence across the system. Ensure the TPS61221's peripheral components (inductors and capacitors) are chosen in line with Texas Instruments' datasheet to ensure stable operation.

3.3V

C12

Capacitance

0.1µ F

SCL-IO22

3.3V

Capacitance

0.1µ F

Capacitance

10µ F

1.8V

3.3V

FB-VOUT

SDA-IO21

1.8V

Capacitance

10µ F

Capacitance

4.7µ F

1.8V

C13

Capacitance

0.1µ F

SDA-IO21

VIN-EN

1.8V

Capacitance

0.1µ F

IC2

Resistance

1k Ω

Resistance

1k Ω

IC4

Reviews

Electrical Rule Checks

Missing Footprints

Reports parts that have no footprint.

Design Rule Checks

Overlapping Copper • 56

Des	Net	Des	Net
IC3:VSS_2	GND	IC3:12	None
IC3:VSS_2	GND	IC3:13	None
IC3:VSS_2	GND	IC3:14	None
IC3:VSS_2	GND	IC3:15	None
IC3:VSS_2	GND	IC3:16	None
Trace 771c	GND	Via	None
Trace 1672	GND	Via	None
Trace 3428	GND	IC3:14	None
Trace 39fb	Net 1	Via	None
Trace 0ffa	Net 6	C1:P1	None
Trace 6d6e	Net 6	IC3:OUT	None
Trace 27fd	Net 6	L1:P2	None
Trace 323e	Net 6	L1:P1	None
Trace 3507	Net 6	L1:P1	None
Trace 3507	Net 6	L1:P2	None
C2:P1	Net 7	Trace 8afe	Net 6
C2:P1	Net 7	Trace ed73	Net 6
Trace 1dd5	Net 8	Via	None
Trace 2e42	Net 8	Via	None
Trace 5aa1	Net 8	Via	None
Trace 9c63	Net 8	Via	None
Trace 43a3	Net 8	C6:P1	None
Trace 222c	Net 8	C6:P1	None
Trace 1696	Net 8	Via	None
Trace 16f3	Net 13	Via	None
Trace 21ab	Net 13	Trace c4bd	Net 1
Trace b480	Net 13	Trace c4bd	Net 1
Trace 0c93	Net 16	R1:P1	Net 13
Trace 0d76	Net 16	R1:P1	Net 13
Trace 45d7	Net 16	Via	None
Trace 596c	Net 16	Via	None
Trace 0788	Net 16	Via	None
Trace 2390	Net 16	R1:P1	Net 13
BT1:+	None	Trace 64f8	Net 6
BT1:+	None	Trace ce80	Net 6
BT1:+	None	Trace d44b	Net 6
C1:P1	None	Trace ed73	Net 6
IC2:ADDR1	None	Trace bfc8	GND
IC2:ADDR1	None	Trace c35e	GND
IC2:EP	None	Trace c35e	GND
OLED1:5V	None	Trace e287	Net 8
U2:L	None	Trace 5862	Net 6
Via	None	Trace 1d08	Net 1
Via	None	Trace 5205	Net 1
Via	None	Trace 9403	Net 1
Via	None	Trace c5c4	Net 1
Via	None	Trace dd40	Net 1
Via	None	Trace f0cb	Net 1
Via	None	Trace 9e3d	Net 13
Via	None	Trace 520c	Net 13
Via	None	Trace 8923	Net 13
Via	None	Trace e2e3	Net 13
Via	None	Trace 4b33	Net 16
Via	None	Trace 7151	Net 16
Via	None	Trace d98d	Net 16
Via	None	Trace da68	Net 16

Invalid Layer

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

Component Overrides • 13

	Designator	Ruleset
	C12:P1	Override rule for P1
	C12:P2	Override rule for P2
	IC2:SCL	Override rule for SCL
	IC2:VDD	Override rule for VDD
	IC4:GND	Override rule for GND
	IC4:VSEL2	Override rule for VSEL2
	IC4:VSEL3	Override rule for VSEL3
	R2:P2	Override rule for P2
	R4:P1	Override rule for P1
	U1:GND	Override rule for GND
	＊｀REF｀＊	Override rule for ${REFERENCE}
	Designator98	Override rule for Designator98
	IC＊＊	Override rule for IC＊＊

Airwires • 12

	Designators	Net
	BT1:-, C8:P2	GND
	C5:P2, C4:P2	GND
	C9:P2, C1:P2	GND
	IC1:GND, C1:P2	GND
	OLED1:GND, C1:P2	GND
	OLED1:GND, C4:P2	GND
	Trace 48fa:Trace 48fa, C8:P2	GND
	Trace c35e:Trace c35e, U1:PGND	GND
	U1:PGND, C4:P2	GND
	U2:GND, C8:P2	GND
	U2:GND, C9:P2	GND
	Trace 520c:Trace 520c, R1:P1	Net 13

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

Reports intrusions from objects of other nets into polygons or fills that have the Protected layout rule applied.

Manufacturing

Manufacturer Part Number • 23

	Designator	MPN
	C1	None
	C2	None
	C3	None
	C4	None
	C5	None
	C6	None
	C7	None
	C8	None
	C9	None
	C12	None
	C13	None
	J1	None
	L1	None
	OLED1	None
	R1	None
	R2	None
	R3	None
	R4	None
	R5	None
	R6	None
	R7	None
	R8	None
	R10	None

Parts Available

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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.

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Pull Up/Pull Down Presence

Beta

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

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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
15.1k
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

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IoT Smartwatch

Controls

Properties

Availability & Pricing

Distributor		Qty 1
	Digi-Key	$11.37–$15.72
	LCSC	$116.49
	Mouser	$24.31

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