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VOXL ESC v1 Datasheet (Work in Progress)

Overview

  Details
Input 2-3 S Li-Po
  XT30 connector
Output 4 channels at 8A maximum continuous current per channel
  Maximum RPM : 17,000RPM for a 12-pole motor (14,500RPM for a 14-pole motor)
  5VDC Power Regulator Output at 6A supporting VOXL Flight, VOXL and Flight Core
  Motor Connectors: Hirose DF3-3S-2C
  Regulated Output Connector: Molex Inc, MPN: 22-05-7045
  LED Connector: DF13A- 4P-1.25H(50)
Features Open-loop control (set desired % power)
  Closed-loop RPM control (set desired RPM), used in PX4 driver
  Control LED colors
  Generate tones using motors
  Real-time RPM feedback
Communications Supported by VOXL Flight, VOXL and Flight Core
  Bi-directional UART (5VDC logic-level, 3.3VDC supported)
PX4 Integration Scheduled to be supported in PX4 1.12
  Available here in developer preview
Resources Manual
  User Guide

Details

Power Input

  • 2-3 S Li-Po
  • reverse polarity protection: yes
  • on/off switch input : yes
  • auxiliary input : yes (only powers ESC MCUs using diode OR, but does not power Mosfets — useful for quick hot-swapping of main battery)

Communication

  • All four ESCs communicate via same bi-directional UART port
  • boot loader 38400 baud rate, firmware 250000 baud rate (firmware baud rate is adjustable)
  • protocol specification
  • protocol sample implementation
  • I2C communication is available on 4-pin Molex connector and is used only by LTC2946 (supported in PX4 as voxlpm driver)
  • PWM input : not available

5V Power Regulator Output

  • 5.15V @ 6A

Performance Specifications

  • Commutation Method : 6-step
  • Maximum RPM : 17,000RPM for a 12-pole motor (14,500RPM for a 14-pole motor).
  • Maximum continuous current per channel: >8A (thermally limited, need to test in specific application)
  • Command update rate > 500Hz (500Hz recommended)

Voltage and Current Sensing

  • LTC2946 high precision voltage and total current sensing, available via separate i2c
  • each MCU on ESC measures it’s own voltage and reports via UART feedback packets
  • individual channel current sensing is not available

LEDs

  • each ESC has control over a low-power RGB LED. Color can be set via UART interface.
  • on-board status LED (blue) for each MCU

Features

  • Open-loop control (set desired % power)
  • Closed-loop RPM control (set desired RPM)
  • Control LED colors
  • Generate tones using motors
  • Real-time RPM feedback

Board Specifications

  • Dimensions: TODO
  • MCU: ATMEGA328P @ 20Mhz
  • Mosfet type : N + P
  • Switching Frequency: 20Khz

Connectors:

Board Connections and Pin-out Specifications

VOXL ESC v1 Board Top

m0004-top.png

VOXL ESC v1 Board Bottom

m0004-bottom.png

Motor CHX

Pin Signal Name
1 CHX_PA_M
2 CHX_PB_M
3 CHX_PC_M

J1 - CH2_LED

  • Connector: DF13A- 4P-1.25H(50)
  • Mating Connector: DF13-4S-1.25C
Pin Signal Name
1 GND
2 CH2_BLU
3 CH2_GRN
4 CH2_RED

J2 - CH3_LED

  • Connector: DF13A- 4P-1.25H(50)
  • Mating Connector: DF13-4S-1.25C
Pin Signal Name
1 GND
2 CH3_BLU
3 CH3_GRN
4 CH3_RED

J6 - CH4_LED

  • Connector: DF13A- 4P-1.25H(50)
  • Mating Connector: DF13-4S-1.25C
Pin Signal Name
1 GND
2 CH4_BLU
3 CH4_GRN
4 CH4_RED

J7 - CH1_LED

  • Connector: DF13A- 4P-1.25H(50)
  • Mating Connector: DF13-4S-1.25C
Pin Signal Name
1 GND
2 CH1_BLU
3 CH1_GRN
4 CH1_RED

J9 - Flight Controller UART

  • Connector: Hirose Electric, MPN: DF13-6P-1.25H(50)
  • Mating Connector: DF13-6S-1.25C cable assemblies (MCBL-00013)
Pin Signal Name
1 NC
2 RX (5V, supports 3.3V)
3 TX (5V, supports 3.3V)
4 NC
5 GND
6 NC

J10 - Power Module Output

  • Connector: Molex Inc, MPN: 22-05-7045
  • Mating Connector: 50-37-5043 based cables, MCBL-00001 (also available here)
Pin Signal Name
1 5VDC
2 GND
3 I2C_SCL
4 I2C_SDA