When designing electronic circuits, we often need to use some common circuits that require redrawing each time, which is both labor-intensive and prone to errors. Therefore, I have designed the circuits I frequently use into modules, allowing for direct use each time. Due to personal limitations, there may be errors in the circuits, and I hope everyone can point them out.
01
RS232 Communication Circuit
Dual-channel 232 communication circuit: 3-wire connection method, corresponding to a female connector, operating voltage 5V, can use MAX202 or MAX232.
02
Transistor Serial Communication
Transistor serial communication: This circuit is built with transistors, simple and low-cost, but it performs very well at low baud rates.
03
Single-channel RS232 Communication
Single-channel 232 communication circuit: 3-wire method, completely equivalent to the above transistor circuit.
04
USB to RS232
USB to 232 circuit: uses PL2303HX, inexpensive and reasonably stable.
05
Reset Circuit
SP706S reset circuit: includes watchdog and manual reset, inexpensive (Maxim’s is much more expensive), R4 is for debugging, solder R4 after debugging.
06
SD Card Module Circuit
SD card module circuit (with lock): This circuit is related to the packaging of the SD card, pay attention to the corresponding packaging. This circuit can control the power of the SD card through the port, quite complete, usable for 5V and 3.3V. However, note that some components differ between 5V and 3.3V.
07
LCM12864 LCD Display Circuit
LCM12864 LCD module (ST7920): This circuit is a common 12864 circuit, inexpensive, with Chinese character library. It can be set to work in serial or parallel mode via the PSB port level, with backlight control function.
08
LCD1602 LCD Display Circuit
LCD1602 character LCD module (KS0066): The most commonly used character LCD module, can only display numbers and characters, can be controlled in 4-bit or 8-bit, with backlight function.
09
Full-Duplex RS485 Circuit
Full-duplex RS485 circuit (with protection function): includes protection, full-duplex 4-wire communication mode, suitable for long-distance communication.
10
Half-Duplex RS485 Circuit
RS485 half-duplex communication module: can select the data transmission direction through the port, with protection power. This module can only operate at 5V.
11
JTAG Debug Interface
ARM JTAG debug interface circuit: quite complete, can be applied to conventional ARM chips, has automatic download function, can use JLINK or ULINK.
12
DC5V Output Circuit
5V power module: This circuit is quite simple, can reach 1.5A if using through-hole components, and can reach 1A if using surface-mount components.
13
DC3.3V Power Output Circuit
3.3V power module: can reach 800mA, very inexpensive, and there are corresponding 1.8/1.2V chips that can be directly replaced.
14
Common Switching Power Supply Circuit
15
DS1302 Clock Circuit
DS1302 digital clock: a very popular clock circuit, easy to use, low cost.
16
AT24C02 Communication Circuit
AT24C02 (EEPROM): The most commonly used EEPROM circuit.
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