USB to 2.1mm DC Booster Cable - 9V

USB-A cable with integrated boost converter that steps up USB 5V to 9VDC on a center-positive 2.1mm barrel jack. Useful for powering 9V devices from a USB port or power bank.

Logical pinout · physical placement not verified

USB 5V input
USB plug input; Adafruit states the booster cable is powered from a USB port or USB battery pack and measurements use a steady 5V input supply.
Type · PowerVoltage · 5V input
DC barrel centre pincentre contact
2.1mm centre-positive DC barrel output for powering 9V devices; Adafruit states the cable powers centre-positive 2.1mm DC barrel jack devices.
Type · PowerVoltage · 9V output, rated 500mA by Adafruit
DC barrel sleeveouter sleeve
Return/ground for the 2.1mm DC barrel output, paired with the centre-positive barrel plug.
Type · GroundVoltage · 0V return

Pin	Position	Type	Function	Voltage
USB 5V input		Power	USB plug input; Adafruit states the booster cable is powered from a USB port or USB battery pack and measurements use a steady 5V input supply.	5V input
DC barrel centre pin	centre contact	Power	2.1mm centre-positive DC barrel output for powering 9V devices; Adafruit states the cable powers centre-positive 2.1mm DC barrel jack devices.	9V output, rated 500mA by Adafruit
DC barrel sleeve	outer sleeve	Ground	Return/ground for the 2.1mm DC barrel output, paired with the centre-positive barrel plug.	0V return

Logical pinout · physical placement not verified

Pin details

3 connections

USB 5V input
USB plug input; Adafruit states the booster cable is powered from a USB port or USB battery pack and measurements use a steady 5V input supply.
PowerVoltage · 5V input
DC barrel centre pin
2.1mm centre-positive DC barrel output for powering 9V devices; Adafruit states the cable powers centre-positive 2.1mm DC barrel jack devices.
PowerVoltage · 9V output, rated 500mA by Adafruit
centre contact
DC barrel sleeve
Return/ground for the 2.1mm DC barrel output, paired with the centre-positive barrel plug.
GroundVoltage · 0V return
outer sleeve

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 5V input, DC barrel centre pin, DC barrel sleeve. 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

Related groups

4 groups

Charging

Single-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

Power supplies

Wall 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

Solar

Solar 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

3D printing

DFRobot 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