It seems you are looking for the schematic (circuit diagram) for a JYMC220BI board, likely from around 2021.

Based on the part number pattern, JYMC usually refers to a power supply / charger / BMS board found in electric scooters, hoverboards, or balance wheels (e.g., from Xiaomi Ninebot or generic self-balancing scooters). The 220 might indicate an input voltage (220V AC), and BI could be a version.

I cannot directly display an image or a PDF, but I can reconstruct a typical schematic text description for such a board (common generic design for 36V or 42V lithium-ion charger).

How to use this information

If you are repairing a JYMC220BI board:

1. Check fuse, bridge rectifier, MOSFET, and output diode – most common failures.
2. Verify VCC on PWM controller (should be 12–18V).
3. Measure optocoupler pins – if TL431 cathode is low, feedback loop is active.
4. If output is 0V but input okay, suspect startup resistors or PWM IC.

For an actual schematic diagram, try:

• Searching "JYMC220BI schematic PDF" on ElektroTanya or Badcaps.net
• Looking for "Ninebot charger schematic" – many are identical
• Checking AliExpress / eBay listings – sometimes sellers show PCB bottom traces

⚠️ Safety warning: This board connects directly to 220V AC. The primary capacitor can hold a lethal charge (310V) for minutes after unplugging. Discharge through a 10kΩ/5W resistor before probing.

Would you like a component-level repair guide for common failure modes (no output, blinking LED, overheating) instead?

JYMC-220B-I (often searched as "jymc220bi") is a variable speed DC motor controller frequently used in Chinese mini-lathes and small machinery

. While a full component-level schematic from 2021 is not publicly released by the manufacturer, the board's layout and wiring are well-documented. Terminal Connections & Wiring

The controller typically features several terminal blocks for basic operation

(2 terminals). Connects to your standard 230VAC (50/60Hz) power supply. Motor Output

(2 terminals). These connect directly to the armature of a DC brush motor. Field Winding

(2 terminals). Used for the field winding if you are using a shunt-wound DC motor. Potentiometer

(2-3 terminals). For connecting an external speed control knob Control Signal . Likely for external logic or safety signals Key Technical Specifications

The JYMC series is designed for reliability in industrial and hobbyist environments Global Electronic Services Motor Compatibility

: Works with Permanent Magnet (PM) and shunt-wound DC motors. Protections

: Features transient voltage protection and current limiting to prevent motor burnout Adjustability

: Includes onboard potentiometers for fine-tuning the minimum and maximum speed, as well as torque/current limits Visual & Repair Guidance If you are troubleshooting a board from 2021 or similar: Safety First

: Ensure the large bulk storage capacitors are fully discharged before handling, as they can retain high voltage even after power is disconnected Visual Inspection

: Check for blackened resistors or blown ICs (common failure points include the TNY series ICs and MOSFETs) Replacement Parts

: Many users find it easier to replace the board entirely or swap common components like the potentiometer if speed control becomes erratic

For detailed teardowns and visual diagrams, you can refer to community-maintained technical guides on platforms like Manuals Plus All About Circuits or specific wiring instructions for a lathe conversion? Treadmill control board circuit diagram Treadmill control board circuit diagram * Imadb. All About Circuits

The JYMC220BI is a common DC motor speed controller, often found in mini lathes or similar machinery. Its 2021 schematic typically includes the following core functional blocks: AC Rectification Stage

: The circuit starts with a bridge rectifier that converts incoming AC power (110V or 220V) into a high-voltage DC bus. PWM Control Core

: At the heart of the schematic is a PWM (Pulse Width Modulation) generator. This regulates the motor's speed by varying the duty cycle of the power delivered to the motor. Power MOSFET/IGBT Switching

: High-power switching transistors (often mounted on a large heatsink) are used to handle the heavy current load of the motor. Feedback & Regulation Tachometer Input

: Some versions include a feedback loop from a speed sensor to maintain constant RPM under varying loads. Current Sensing

: A low-ohm shunt resistor is typically used to monitor motor current and provide over-current protection. User Interface Connectors : The schematic outlines dedicated headers for: Potentiometer : For manual speed adjustment. Forward/Reverse Switch : Integrated logic to safely swap motor polarity. Emergency Stop (E-Stop)

: A critical safety input that instantly cuts power to the motor. Common Troubleshooting Points in the Schematic

When reviewing the 2021 schematic for repair or modification, focus on these common failure points: The Main Fuse

: Often integrated directly into the AC input line on the PCB. Freewheeling Diode

: A large diode placed across the motor outputs to protect the switching transistors from inductive spikes. Voltage Regulator (e.g., 7812 or 7805)

: Used to step down the high DC bus voltage to power the low-voltage control ICs.

If you are looking for specific component values or terminal wiring diagrams, you may find detailed visual guides and community discussions on platforms like Electronics Stack Exchange or hobbyist forums such as Model Engineer's Workshop on the board, or are you trying to troubleshoot a particular issue like a motor not starting?

The JYMC-220B-I (often referred to as JYMC220BI) is a widely used DC brush motor speed controller specifically designed for mini lathes like the CJ0618 and WM210V. As of 2021, these boards remain the standard for high-torque, variable-speed control in small workshops. Core Technical Specifications

This board is designed to convert high-voltage AC input into a regulated DC output for brushed motors: Input Voltage: 230 VAC (50/60 Hz). Output Voltage: 0–180 VDC. Rated Current: 12 ADC.

Compatibility: Ideal for motors ranging from 0.5 HP (approx. 375W) up to 1100W, depending on the specific lathe model. Typical Wiring Schematic & Connections MINI Lathe DC Motor Speed Control Board Instruction Manual

Here’s a solid draft for a post covering the JYMC220BI schematic (2021). It’s suitable for a blog, forum (e.g., EEVblog, Reddit r/electronics), or technical documentation.

What is the JYMC220BI?

In short, the JYMC220BI is a multifunction battery management + MCU hybrid. Unlike a dedicated chip (like the TP4056 for charging or an STM32 for control), this IC integrates:

• Linear charging (typically 4.2V, 500mA–1A)
• Boost converter (5V output for USB-OTG or LED driving)
• Key/button sensing (single or dual buttons)
• LED indicators (4 or 5 pin outputs)
• Load switching (MOSFET drivers inside)

The "2021" revision differs from older versions (2018, 2019) by adjusting the boost feedback divider and moving the battery under-voltage lockout (UVLO) from 2.9V to 3.0V – a minor but critical change for lithium-ion longevity.

The 2021 Schematic Oddity: R_SET and Boost Feedback

Earlier revisions used a fixed 1.2V reference for the boost. The 2021 version introduces a resistor divider between VOUT and FB (pin not even listed in generic datasheets!).

Through trial and error, repair forums found that the 2021 output voltage follows:

[ V_OUT = 1.25V \times (1 + \fracR_topR_bottom) ]

Where ( R_top ) is between VOUT and FB, and ( R_bottom ) is FB to GND.
If you see 5.2V instead of 5.0V, replace the top resistor (typically 100k) with 91k.

Revisions from 2020 to 2021 Schematic

• Improved EMI filtering (added common-mode choke on some variants).
• Changed inductor from radial to shielded SMD type.
• Updated controller IC to a lower standby power version (<100 mW).

Key Pins on the 2021 Schematic

Most JYMC220BI designs use a 16-pin QFN or 14-pin SOP package. Based on traced 2021 PCBs, here’s the functional pinout:

| Pin | Name | Function in 2021 Rev | |-----|----------|-----------------------------------------------| | 1 | BAT | Battery positive (direct connection) | | 2 | GND | Power ground | | 3 | CHRG | Open-drain charge indicator (active low) | | 4 | FULL | Open-drain full indicator | | 5 | KEY1 | Single button input (pull-up internal) | | 6 | LED1-4 | Multiplexed LED outputs (sink current) | | 7 | SW | Inductor pin for boost converter (to 2.2µH) | | 8 | VOUT | 5V boosted output | | 9 | ISET | Charge current set (resistor to GND) | | 10 | NTC | Battery thermistor input (10k NTC typical) |

Note: Not all pins are documented – the 2021 schematic adds a "soft-start" capacitor on a hidden pin 11.