USB pass-through current and voltage meter with an ATtiny85, INA169 high-side current sense, and LED strip display. Provides analog and TTL serial output for data-logging; data is transparently passed at any USB speed.
5 V USB bus input from the host/charger side, monitored by the gauge.
Ground/reference from the host/charger side.
USB data line passed transparently through the gauge.
USB data line passed transparently through the gauge.
5 V USB bus output to the attached device after the current-sense path.
Ground/reference to the attached device.
USB data line passed transparently to the attached device.
USB data line passed transparently to the attached device.
9600 baud TTL serial debug/data output with readable voltage, current, and wattage.
| 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 |
5 V USB bus input from the host/charger side, monitored by the gauge.
Ground/reference from the host/charger side.
USB data line passed transparently through the gauge.
USB data line passed transparently through the gauge.
5 V USB bus output to the attached device after the current-sense path.
Ground/reference to the attached device.
USB data line passed transparently to the attached device.
USB data line passed transparently to the attached device.
9600 baud TTL serial debug/data output with readable voltage, current, and wattage.
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.
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.
1-Way 18650 Battery Holder visual preview1-Way 18650 Battery Holder
18650 Battery Holder Case - 2 Slot with Switch visual preview18650 Battery Holder Case - 2 Slot with Switch
18650 Battery Holder Case - 4 Slot visual preview18650 Battery Holder Case - 4 Slot
18650 Battery Protection Module (12V 10A) visual preview18650 Battery Protection Module (12V 10A)
2 x 18650 Battery Holder with DC2.1 Power Jack visual preview2 x 18650 Battery Holder with DC2.1 Power Jack
2 x AA Battery Holder with Knife Switch visual preview2 x AA Battery Holder with Knife Switch
2 x AA Battery Holder with On/Off Switch & JST PH Connector visual preview2 x AA Battery Holder with On/Off Switch & JST PH Connector
2 x AA Open Battery Holder with JST PH Connector visual preview2 x AA Open Battery Holder with JST PH Connector
2 x AAA Battery Holder with On/Off Switch & JST PH Connector visual preview2 x AAA Battery Holder with On/Off Switch & JST PH Connector
2 x AAA Battery Holder with Switch visual preview2 x AAA Battery Holder with Switch
2 x AAA Open Battery Holder with JST PH Connector visual preview2 x AAA Open Battery Holder with JST PH Connector
2 x CR2032 Coin Cell Battery Holder - 6V output - On/Off switch visual preview2 x CR2032 Coin Cell Battery Holder - 6V output - On/Off switch
7.4V Lipo Battery Charger visual previewSingle-cell LiPo chargers (TP4056, MicroUSB/Type-C modules), charger/booster combos (PowerBoost 500/1000, Lipo Rider Plus 5V/2.4A), I2C fuel gauges (MAX17048, LC709203F) and Qi wireless charging coils.
Power · Chargers & fuel gauges · 47 parts
10W 4 USB Power Adapter visual previewWall adapters (5V–24V), adjustable and fixed buck/boost/buck-boost converters (MT3608, LM2596-class), USB-C PD triggers (HUSB238), breadboard supplies, DIN-rail units and passive barrel-jack adapters.
Power · Supplies & regulators · 147 parts
3.8 / 1.3mm or 3.5 / 1.1mm to 5.5 / 2.1mm DC Jack Adapter Cable visual previewSolar panels from 1.5V 250mA flexible film to 18V 10W polysilicon, MPPT solar power managers (DFRobot 5V and 9V/12V/18V, Waveshare 6V–24V), bq25185 charger boards and LTC3588 energy-harvesting breakouts.
Power · Solar power · 28 parts
1.75mm PLA (1kg) - Black visual previewDFRobot 1.75 mm PLA in 1 kg spools makes up the bulk of the group, in over 15 colors. Specialty options include PVA in both diameters, NinjaFlex flexible filament, Proto-Pasta conductive PLA, and wood-fill. OverLord printer spares and OverLord printers round out the hardware side.
Tools & prototyping · 3D printing · 53 parts