Hardware¶
PCB of EXT3-2 board¶
| Connector | Description |
|---|---|
| J2 | 24 pins connector for connecting with from 1.52” to 7.4” EPD |
Driving circuit of EXT3-2¶
Your EPD should connect with 24-pins (J2) of ZIF connector below.
| EPD group | Screen sizes |
|---|---|
| G1 | 1.52", 1.54”, 2.06", 2.13”, 2.66”, 2.71”, 2.90” and more |
| G2 | 3.7”, 4.2”, 4.37” and more |
| Circuit element | EPD group | Specification |
|---|---|---|
| L1 | G1, G2 | 10 uH (default) |
| R1 | G1, G2 | 0.47 ohm (default) |
| C1 | G1, G2 | 1 uF 6.3V (default) |
| C2 | G1, G2 | 1 uF 25V (default) |
| Circuit element | Specification | Vendor |
|---|---|---|
| Inductor | 10uH ATNR4010100MT ±20% 0.8A | Arlitech |
| 47uH ETPRH3D16B-470M 0.3A | Arlitech | |
| Transistor (1) | Si1308EDL or Si2300DS, SOT-23 N-Channel | Vishay |
| MCH3478 SOT-23 N-Channel 30V/2A | ON-Semi | |
| PJ2306 SOT-23 N-Channel 30V/3.2A | Panjit | |
| NTR4170N SOT-23 N-Channel 30V/3.1A | ON-Semi | |
| PMV100ENEAR or PMCB60XN, SOT-23 N-Channel | Nexperia | |
| DMN3053L, SOT-23 N-Channel | Diodes Inc. | |
| Diode (2) | SS2040FL SOD-123FL | Panjit |
| Capacitors | 25V 0603 |
Info
- Si1308EDL, MCH3478 or PJ2306 is a N-Channel Power MOSFET. The specification of selection criteria is RDS<200m ohm (the lower the better), VDDS=30V, VGS<2.5V@Id=0.5A or less.
- SS2040FL is a Schottky diode needs the VF as lower as possible, e.g. 0.2 to 0.4V and the repetitive peak reverse voltage > 25V.
Pinouts & BOM of EXT3-2¶
J4 & J5 Pin assignment¶
| Pin # | Symbol | Description |
| 1 | VCC | VCC 3.3V |
| 2 | SCK | SPI CLK, serial communication clock input |
| 3 | BUSY | Busy state output pin L: EPD driver is busy, data/command is transforming H: host side can send command or data to EPD driver |
| 4 | D/C | Serial bus for controlling data or command L: command; H: data |
| 5 | RST | Reset signal input |
| 6 | NC | Not used |
| 7 | MOSI | SPI MOSI, serial communication data input |
| 8 | V_CTRL | Power toggle pin |
| 9 | ECSM | Master chip select pin of EPD |
| 10 | GND | Ground |
BOM¶
| Item | Description | Vendor | Q’ty | Location |
|---|---|---|---|---|
| 1 | CAP 1uF 25V 0603 Y5V | 8 | C2,C4,C5,C6 C8,C9,C10,C11 |
|
| 2 | CAP 4.7uF 25V 0603 Y5V | 2 | C1,C7 | |
| 3 | CAP 100nF 25V 0603 Y5V | 1 | C3 | |
| 4 | DIODE SS2040FL SOD-123FL | PANJIT | 3 | D1,D2,D3 |
| 5 | CONN 24P 6702A24-000000-G2-R Pitch=0.5mm | STARCONN | 1 | J1 |
| 6 | PIN Header.FH P2.54 DIP 10*1PIN.G (90 deg/1*10P/Pitch 2.54mm) |
1 | J2 | |
| 7 | IND 10uH ATNR4010100MT +-20% 0.8A H=0.9mm | ARLITECH | 1 | L1 |
| 8 | MOSFET MCH3478 SOT-23 N-Channel 30V/2A | ON Semiconductor | 2 | Q2,Q4 |
| 9 | MOSFET AP2305 SOT-23 P-Channel | 2 | Q1,Q3 | |
| 10 | RES 0.47 ohm 0603 1% 1/10W | 1 | R2 | |
| 11 | RES 33k ohm 0603 5% 1/10W | 2 | R1 | |
| 12 | PCB EXT3-2 board-v01 | 1 | PCB/ EXT3-2 board-v01 |