Project Files of 8520 Coreless Motor Library for Proteus V1.0 (Micro Drone Motor)

8520 CORELESS MOTOR LIBRARY FOR PROTEUS - V1.0 (the 8.5 x 20 mm coreless
brushed DC motor of micro drones, with its propeller)
Designed by The Engineering Projects
www.TheEngineeringProjects.com

IMPORTANT LINKS
Article (read it first - pictures, step by step, every feature explained):
  https://www.theengineeringprojects.com/2026/11/8520-coreless-motor-library-for-proteus-v1-0.html
Report a bug or suggest a feature (our forum):
  https://www.theengineeringprojects.com/forum/category/motor-driver-proteus-library
The demo runs on our Arduino UNO V4.0 (included) - working LEDs, RESET and a
built-in serial monitor - its own article:
  https://www.theengineeringprojects.com/2026/10/arduino-uno-library-for-proteus-v40.html
The demo's driver is our TB6612FNG Motor Driver - a SEPARATE library, not in
this package: download and install it first - its own article:
  https://www.theengineeringprojects.com/2026/10/tb6612fng-motor-driver-library-for-proteus-v1-0.html
Support us (the libraries are free):
  https://www.theengineeringprojects.com/donate

FILE STRUCTURE
8520-Coreless-Motor-TEP-v1.0/
|-- Proteus Library Files/
|   |-- ArduinoV4TEP.LIB                              201.9 KB   TEP Arduino boards V4.0 (UNO) -> LIBRARY
|   |-- TEPCORELESS.LIB                                22.0 KB   the library -> LIBRARY folder
|-- Proteus Model Files/
|   |-- TEPARDUINO.DLL                                883.5 KB   the Arduino board model -> MODELS folder
|   |-- TEPCORELESS.DLL                               320.5 KB   the model -> MODELS folder
|-- Proteus Simulation/
|   |-- Coreless_Demo.hex                              17.2 KB   the demo firmware
|   |-- Coreless-Motor-TB6612-ArduinoUnoV4.pdsprj      23.5 KB   the demo project
|   |-- TEPARDUINO.DLL                                883.5 KB   copy of the board model
|   |-- TEPCORELESS.DLL                               320.5 KB   copy of the model
|-- Arduino Code/
|   |-- Coreless_Demo/Coreless_Demo.ino                 4.2 KB   the demo sketch (source of the .hex)
|-- README.txt                                        ~16.7 KB   this file
Total: 2.63 MB (unzipped). The C++ source code of the models is not included.

WHAT IS IT?
A simulation model of the 8520 coreless motor - the 8.5 mm x 20 mm brushed DC
motor of micro quadcopters (the 65 - 100 mm "brushed" drones) and small fast
robots, here with its 46 mm two-blade propeller. "Coreless" means its winding
is a self-supporting copper basket with no iron inside: the rotor is light, it
speeds up in a blink, and its inductance is tiny. Our own model:
  * The windings between + and - are in the circuit: 1.0 ohm (25 C, it warms)
    and 35 uH behind the back-EMF, 0.65 mV per rad/s (14,700 RPM per volt).
    The L/R of only 35 us means the current follows the voltage within tens
    of microseconds - so a slow PWM chops it: at 490 Hz every pulse drives it
    up and every gap (the H-bridge's short brake) drives it negative.
  * The rotor and the propeller: the motor's torque against the friction and
    the propeller's drag; the propeller's thrust (Ct 0.10, Cq 0.008 at its
    diameter). Free (no propeller) it runs at about 52,000 RPM on 0.12 A; with
    the 46 mm propeller on 3.7 V through the TB6612FNG about 32,000 RPM, 1.0 A
    and 16 g of thrust; 90 % of the speed in about 0.25 s.
  * The heat: the windings warm with the RMS current (I^2 R) - a coreless
    winding has no iron to soak the heat up, and burns out above about 100 C.
  * The watch: the drive (DC, or PWM with its frequency), STEADY
    (speed, thrust, current and its RMS), STOPPED, REVERSED, and the warnings:
    CHOPPED CURRENT (a PWM under 5 kHz), HOT, STALLED, OVER-VOLTAGE (over 4.2
    V: an 8520 is a 1S motor), OVER-CURRENT (over 1.5 A RMS for 2 s).
The symbol shows the motor from the side, upright in the clamp at the end of a
drone arm: the silver can with its brass bearing and the shaft, the red
propeller on its black hub, and the red (+) and blue (-) leads to the pins. At
Run the propeller turns (a red blur when fast) and arrows show the air it
pushes - down with the thrust, up when it runs backwards. The plate, the ON
LED (green while current flows), the air arrows, the rating line and the strip
under the plate (RPM, THRUST, CURRENT, OPEN PANEL) are TEP additions; the real
motor has none of them.

ONE DEVICE (search "coreless" or "8520" in Pick Devices):
  CORELESS8520TEP    "8520 Coreless Motor V1.0"   (category Electromechanical >
                     Motors), model TEPCORELESS.DLL
  The pop-up panel "TEP 8520 Coreless Motor" opens at Run (and with OPEN PANEL
  on the strip) - the look of the TEP Serial Monitor. Tabs Motor, Graphs,
  Event log and Check; gear and ? icons for Settings and Help; the palette
  icon switches the theme:
    Motor      the state in big letters (RUNNING - 21600 RPM, 7.3 G OF
               THRUST, 0.50 A; CHOPPED; COASTING; STALLED; STOPPED); the motor
               and its propeller with the air; the live values (speed, thrust,
               the current's average and RMS, the voltage, the drive, the
               power in, the windings); the last 5 ms: the current and the
               voltage - the PWM's pulses and how the current follows them.
    Graphs     the speed, the thrust and the current (average and RMS) over
               the last 10, 30 or 60 s. Live / Freeze.
    Event log  the drive ("PWM 20.0 kHz = 1.97 V average across the motor
               (forward)"), STEADY ("STEADY - 21900 RPM, 7.5 g of thrust, 0.48
               A (0.59 A RMS) at 1.97 V"), STOPPED, REVERSED, the warnings;
               filters All / Speed / Warnings, Pause, Clear
    Check      Good for: a motor that runs hot, gives little thrust, whines or
               will not turn - the voltage, the drive, the current, the
               thrust, the direction, the windings, with tips
    Settings   theme, text size, open at Run, window size
    Help       report a bug, suggest a feature, article, updates, donate,
               forum; Copy diagnostics for a bug report

TEST STATUS
V1.0: verified in Proteus 8.5 on 29 Oct 2026 (the demo project as shipped: an
A3 sheet, an Arduino UNO V4.0 with its built-in monitor, our TB6612FNG driver
- its pop-up version, from its own library - on a +3.7V rail, the motor with
the 46 mm propeller and RV1; all pop-ups open). What the run showed:
  * The project loads and starts cleanly; RV1 at 60 % at 20 kHz: "PWM 20.0
    kHz = 1.97 V average across the motor (forward)", "STEADY - 21974 RPM,
    7.5 g of thrust, 0.49 A (0.57 A RMS) at 1.98 V"; the ON LED lit, the
    propeller a blur, the air arrows down. The TB6612FNG's pop-up: PWMA "PWM
    60 % at 20000 Hz", VM 3.70 V, 0.489 A.
  * "throttle 100": "steady 3.20 V across + / - (forward)", "STEADY - 32412
    RPM, 16.3 g of thrust, 0.99 A (0.99 A RMS) at 3.20 V".
  * "throttle 60" and "f 490": "CHOPPED CURRENT - PWM 490 Hz: it swings -0.99
    to 1.46 A every pulse (L/R 35 us); use 20 kHz", "STEADY - 22023 RPM, 7.5
    g of thrust, 0.47 A (1.25 A RMS) at 1.98 V" - the same thrust as at 20
    kHz with more than twice the RMS current.
  * "f 20000", then "rev": "STEADY - 21907 RPM, -7.5 g of thrust DOWNWARD,
    0.48 A (0.57 A RMS) at 1.98 V", "REVERSED - the propeller pushes the air
    the other way: 7.5 g downward".
  * "stop" (the short brake): "drive off: + and - at the same level (coasting
    or braking)"; the windings at 29 C after the run.
  Plus automatic checks on a PC, 0 failed: 12 on the motor (3.7 V DC: 32,416
  RPM, 0.99 A, 16.3 g, 5.1 g per W, 90 % of the speed in 243 ms; no
  propeller: 51,732 RPM, 0.12 A; 60 % at 20 kHz: 0.59 A RMS, no warning, the
  PWM read 20 kHz; 60 % at 490 Hz: 1.27 A RMS, swinging -0.99 to 1.47 A, the
  warning; reverse; 5 V: OVER-VOLTAGE; 40 s at 80 %: 52 C at 490 Hz against
  36 C at 20 kHz; every event text fits); 2 on the pop-up pages rendered; the
  demo project read back from disk (69 checks: devices, pins, wires, labels,
  no wire through a part, no crossing).

INSTALLATION (about 2 minutes)
1. Close Proteus. Extract the WHOLE ZIP to a normal folder (e.g. Desktop).
2. Copy everything in "Proteus Library Files" (TEPCORELESS.LIB and our Arduino
   library V4.0, ArduinoV4TEP.LIB) to the LIBRARY folder of Proteus, for
   example:
     C:\Program Files (x86)\Labcenter Electronics\Proteus 8 Professional\LIBRARY
   (on some PCs: C:\ProgramData\Labcenter Electronics\Proteus 8 Professional\
   LIBRARY - use the folder that already holds Proteus's own .LIB files).
3. Copy TEPCORELESS.DLL and TEPARDUINO.DLL from "Proteus Model Files" to the
   MODELS folder (...\Proteus 8 Professional\MODELS). The demo's driver is NOT
   in this package: install our TB6612FNG Motor Driver library the same way
   (its own ZIP - see IMPORTANT LINKS): TEPTB6612.LIB and TEPTB6612.DLL.
4. Delete TEPCORELESS.IDX from the LIBRARY folder if it is there.
5. Start Proteus. In Pick Devices (P) search "coreless".

RUN THE DEMO
"Proteus Simulation\Coreless-Motor-TB6612-ArduinoUnoV4.pdsprj" - keep the .hex
file and the DLLs beside the project (with the TB6612FNG library installed).
  ARD1: Arduino UNO V4.0 running Coreless_Demo.hex, its serial monitor built in
        (window "TEP Arduino UNO - ARD1").
  DRV1: our TB6612FNG driver (pop-up version, a separate library): PWMA on D9,
        AIN2 on D8, AIN1 on D7, STBY on VCC, VM on +3.7V (a 1S LiPo), VCC,
        GND - by net labels.
  M1:   the motor: + on AO1, - on AO2 (motor A) - straight wires.
  RV1:  10k pot on A0 (the throttle, 0 - 100 %; 60 % at power-up).
  1. Press Run. The monitor and the two pop-ups open (move them aside). The
     motor spins up to RV1's throttle at 20 kHz.
  2. Type in the monitor and press Send: throttle 100, throttle 60, f 490,
     f 20000, rev, fwd, stop, knob.
  3. Double-click M1: PROP (46 / 55 / NONE).
  4. The pop-up: Motor, Graphs, Event log, Check.

WIRING (the same idea on a real motor)
  TB6612FNG       Arduino UNO / supply
   PWMA           D9 (Timer1: a 20 kHz PWM)
   AIN1, AIN2     D7, D8 (forward: HIGH / LOW; both HIGH: the short brake)
   STBY, VCC      5 V (the UNO's 5V)
   VM             the motor's battery (1S LiPo, 3.7 - 4.2 V), GND common
  Motor           TB6612FNG
   + (red)  / - (blue)   AO1 / AO2
In the sketch (no library needed): Timer1 in fast PWM mode 14, TOP = ICR1:
  TCCR1A = _BV(COM1A1) | _BV(WGM11);
  TCCR1B = _BV(WGM13) | _BV(WGM12) | _BV(CS10);  // no prescaler
  ICR1 = 799;                                    // 16 MHz / 800 = 20 kHz
  OCR1A = 480;                                   // 60 %
REAL HARDWARE:
 * Use a fast PWM: 20 kHz or more (micro drone flight controllers use 16 -
   32 kHz). analogWrite()'s 490 / 980 Hz chops a coreless motor's current:
   more heat, more battery drain and a whine, for the same thrust.
 * Drive it with an H-bridge (the TB6612FNG: 1.2 A, 3.2 A peak) or a logic
   MOSFET (AO3400, SI2302) with a Schottky diode across the motor - an 8520
   draws over 1 A, and 3 - 4 A when it starts or stalls - never a pin.
 * A 1S LiPo (3.7 V, 4.2 V full) is its supply; 5 V shortens its life.
 * Mind the propeller: CW and CCW motors (red / blue or black / white leads)
   and matching propellers; a propeller on backwards pushes the wrong way.
 * Do not stall it: a blocked coreless motor burns out in seconds.

THE DEMO SKETCH ON THE SERIAL MONITOR (Coreless_Demo V1.0, 9600 baud)
  throttle 80   a fixed throttle (0 - 100 %)   knob      RV1 sets it again
  f 490         the PWM frequency (Hz)         f 20000   back to 20 kHz
  rev / fwd     the direction                  stop      the short brake
  help          the list
EXPECTED MONITOR OUTPUT
  8520 Coreless Motor demo - The Engineering Projects
  TB6612FNG on 3.7 V: PWMA D9 (Timer1, 20 kHz), AIN1 D7, AIN2 D8. RV1 sets the throttle.
  Commands: throttle 80 | knob | f 490 | f 20000 | rev | fwd | stop | help
  Throttle 60 % at 20.0 kHz, forward

PROPERTIES (double-click the part > Edit Properties)
  PROP       the propeller: 46 or 55 (mm), or NONE; default 46
Every run starts again from the properties.

TROUBLESHOOTING
* It does not turn and nothing is logged: no drive - the TB6612FNG has no VM,
  STBY is low, or its inputs are not driven.
* CHOPPED CURRENT: the PWM is too slow for the windings (under 5 kHz) - set
  Timer1 to 20 kHz or more.
* It turns the wrong way, the thrust is negative (REVERSED): swap AIN1 /
  AIN2, or the motor's leads.
* HOT: a chopped current, a stall, or too much voltage - a coreless winding
  burns out above about 100 C.
* OVER-VOLTAGE: more than 4.2 V average across the motor - a 1S motor.
* The part is not simulated: TEPCORELESS.DLL is missing from MODELS and from
  the project folder. No driver: install our TB6612FNG library (TEPTB6612.LIB
  / .DLL). No UNO / no monitor window: TEPARDUINO.DLL, or click the UNO's USB
  port.
* The pop-up does not appear: click OPEN PANEL on the strip, or turn "Open the
  panel at Run" on its Settings page back on.

BUG REPORTS AND FEATURE REQUESTS
Please post them in our forum with a screenshot, the Serial Monitor text, the
simulation log and the pop-up's Copy diagnostics text:
  https://www.theengineeringprojects.com/forum/category/motor-driver-proteus-library

SUPPORT US
This library is free. If it saves you time, please support our work:
  https://www.theengineeringprojects.com/donate

LICENCES AND THIRD-PARTY NOTES
* The motor model (TEPCORELESS.DLL), the symbol and artwork and the Arduino
  Library V4.0 (ArduinoV4TEP.LIB / TEPARDUINO.DLL) are made by The Engineering
  Projects. The model is an independent implementation written from the
  typical data of 8520 coreless motors and small propellers. The models use
  only standard Windows libraries; no Visual C++ redistributable is needed.
  The C++ source code is not included. The demo's driver, our TB6612FNG Motor
  Driver library (TEPTB6612.LIB / TEPTB6612.DLL), is a separate download.
* The demo's .hex is built from the demo sketch and the Arduino AVR core 1.8.6,
  which includes LGPL-licensed code; its source code is available at
  https://github.com/arduino/ArduinoCore-avr/tree/1.8.6
* Proteus is a product of Labcenter Electronics and is not included. Arduino is
  a trademark of Arduino SA. This library is not made or endorsed by any motor
  or drone maker, Arduino or Labcenter.

REBUILDING THE FIRMWARE (OPTIONAL)
The HEX file is supplied; Arduino IDE is not needed to run the demo. To edit
the sketch, open Arduino Code\Coreless_Demo\Coreless_Demo.ino, select Arduino
Uno and use Sketch > Export Compiled Binary. The sketch needs 6,248 bytes of
flash (19 % of the UNO) and 284 bytes of RAM.

MODEL SCOPE AND LIMITS
Modelled: the windings (resistance with its temperature, inductance, back-EMF),
the rotor (friction, inertia), the propeller (thrust and drag against the
speed, both ways), the windings' heating, the watch's states and warnings.
How it runs: the windings are in the circuit as a backward-Euler companion over
the analog step (a conductance and a source); the rotor and the heat run in
sub-steps of at most 20 us between the analog points, which are held to 12.5
us while the motor is driven or turns (1 ms at rest), so every PWM pulse is
seen. A run is therefore slower than real time.
Not modelled: the brushes' arcing and wear, the commutation ripple, the air's
own flow (the propeller in a frame or near the ground), the drone around it.

VERSION
TEP 8520 Coreless Motor library V1.0 (Oct 2026). Device CORELESS8520TEP
(TEPCORELESS.LIB / TEPCORELESS.DLL). Demo sketch Coreless_Demo V1.0. Demo
driver: TB6612ADVTEP (TEP TB6612FNG Motor Driver library V1.0, a separate
library). Demo board: ARDUINO UNO V4.0 (TEP Arduino Library V4.0) with its
built-in serial monitor.