Name: Adafruit USB Power Gauge Mini-Kit
Brand: Adafruit
SKU: 1549

Logical pinout · physical placement not verified

USB upstream plug VBUSUSB plug power contact
5 V USB bus input from the host/charger side, monitored by the gauge.
Type · PowerVoltage · USB 5 V nominal; green LED indicates bus above 4.5 V
USB upstream plug GNDUSB plug ground contact
Ground/reference from the host/charger side.
Type · GroundVoltage · 0 V
USB upstream plug D+USB plug D+ contact
USB data line passed transparently through the gauge.
Type · USBVoltage · USB signalling
USB upstream plug D-USB plug D- contact
USB data line passed transparently through the gauge.
Type · USBVoltage · USB signalling
USB downstream jack VBUSUSB jack power contact
5 V USB bus output to the attached device after the current-sense path.
Type · PowerVoltage · USB 5 V nominal; current measured up to 1 A display range, safe up to 2 A per product page
USB downstream jack GNDUSB jack ground contact
Ground/reference to the attached device.
Type · GroundVoltage · 0 V
USB downstream jack D+USB jack D+ contact
USB data line passed transparently to the attached device.
Type · USBVoltage · USB signalling
USB downstream jack D-USB jack D- contact
USB data line passed transparently to the attached device.
Type · USBVoltage · USB signalling
TXTX pad/pin on gauge PCB
9600 baud TTL serial debug/data output with readable voltage, current, and wattage.
Type · UARTVoltage · TTL serial level from onboard ATtiny85 circuit

Pin	Position	Type	Function	Voltage
USB upstream plug VBUS	USB plug power contact	Power	5 V USB bus input from the host/charger side, monitored by the gauge.	USB 5 V nominal; green LED indicates bus above 4.5 V
USB upstream plug GND	USB plug ground contact	Ground	Ground/reference from the host/charger side.	0 V
USB upstream plug D+	USB plug D+ contact	USB	USB data line passed transparently through the gauge.	USB signalling
USB upstream plug D-	USB plug D- contact	USB	USB data line passed transparently through the gauge.	USB signalling
USB downstream jack VBUS	USB jack power contact	Power	5 V USB bus output to the attached device after the current-sense path.	USB 5 V nominal; current measured up to 1 A display range, safe up to 2 A per product page
USB downstream jack GND	USB jack ground contact	Ground	Ground/reference to the attached device.	0 V
USB downstream jack D+	USB jack D+ contact	USB	USB data line passed transparently to the attached device.	USB signalling
USB downstream jack D-	USB jack D- contact	USB	USB data line passed transparently to the attached device.	USB signalling
TX	TX pad/pin on gauge PCB	UART	9600 baud TTL serial debug/data output with readable voltage, current, and wattage.	TTL serial level from onboard ATtiny85 circuit

Logical pinout · physical placement not verified

Pin details

9 connections

USB upstream plug VBUS
5 V USB bus input from the host/charger side, monitored by the gauge.
PowerVoltage · USB 5 V nominal; green LED indicates bus above 4.5 V
USB plug power contact
USB upstream plug GND
Ground/reference from the host/charger side.
GroundVoltage · 0 V
USB plug ground contact
USB upstream plug D+
USB data line passed transparently through the gauge.
USBVoltage · USB signalling
USB plug D+ contact
USB upstream plug D-
USB data line passed transparently through the gauge.
USBVoltage · USB signalling
USB plug D- contact
USB downstream jack VBUS
5 V USB bus output to the attached device after the current-sense path.
PowerVoltage · USB 5 V nominal; current measured up to 1 A display range, safe up to 2 A per product page
USB jack power contact
USB downstream jack GND
Ground/reference to the attached device.
GroundVoltage · 0 V
USB jack ground contact
USB downstream jack D+
USB data line passed transparently to the attached device.
USBVoltage · USB signalling
USB jack D+ contact
USB downstream jack D-
USB data line passed transparently to the attached device.
USBVoltage · USB signalling
USB jack D- contact
TX
9600 baud TTL serial debug/data output with readable voltage, current, and wattage.
UARTVoltage · TTL serial level from onboard ATtiny85 circuit
TX pad/pin on gauge PCB

Start wiring

3.3 V · 5 V

Adafruit lists its single-cell LiPo and Li-ion packs as 3.7 V nominal, with output reaching 4.2 V when fully charged.

Module pins: USB upstream plug VBUS, USB downstream jack VBUS, USB upstream plug GND, USB downstream jack GND, TX. Schematik maps them to your board in the app.

Batteries

103 other options

9V alkaline cells, CR2032 coin cells, 3.7V LiPo packs (1000–1200mAh), 7.4V 2S LiPo, 18650 Li-ion holders (1–6 cells), AA/AAA holders in every configuration, and snap leads with barrel adapters.

View all 103

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4 groups

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3D printing

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