描述

一、PCA9685簡介

The PCA9685 is an I2C-bus controlled 16-channel LED controller optimized for LCD

Red/Green/Blue/Amber (RGBA) color backlighting applications. Each LED output has its
own 12-bit resolution (4096 steps) fixed frequency individual PWM controller that operates
at a programmable frequency from a typical of 40 Hz to 1000 Hz with a duty cycle that is
adjustable from 0 % to 100 % to allow the LED to be set to a specific brightness value.
All outputs are set to the same PWM frequency.

PCA9685 also has a built-in oscillator for the PWM control.
However, the frequency used for PWM control in the PCA9685 is adjustable from
about 40 Hz to 1000 Hz as compared to the typical 97.6 kHz frequency of the
PCA9635. This allows the use of PCA9685 with external power supply controllers. All
bits are set at the same frequency.

The PCA9685 has 4096 steps (12-bit PWM)

二、產品特色

1. J3 Mini USB 5V input for PWM V+ & GPIO output pin 10 V+

J2 2P Terminal Block 5V input for PWM V+ & GPIO output pin 10 V+

2. J1 Rs-Pi V2  GPIO output

3 JP13  DA0 ~ DA7   U14 Port A    . JP14 BA0 ~ BA7     U14 Port B

4. R64,R65,R66 ( for  U14 Address select  A0,A1,A2)

5. U14 I2C 23017 -1  Port A,B            23017 Datasheet

6. U15  uln2803

7. U3 PCA9685 (PWM Port 0 ~ 15)       PCA9685Data Sheet

8. R10,R11,R12,R13,R14,R15( for U3 Address select A0,A1,A2,A3,A4,A5)

plug in Raspberry Pi with Servo motor

in i2cdetect  you can found 2 device in system (21,41)

21 –  23017     41 – 9685

三、Scratch驅動應用範例 Detail

(1) Servo Motor control

2 Servo in  channel 0 & channel 7

Command “SE”+ “PWM (0-15)” + “a” +”angle”  for Address 41

se7a10   –> channel 7 servo move 10 angle  address 41

se7a-10  –> channel 7 servo move -10 angle address 41

se0a10   –> channel 0 servo move 10 angle  address 41

se0a-10  –> channel 0 servo move -10 angle  address 41

(2) PWM  LED output demo

LED module (Blue, Green,Yellow,Red)

 

LED Scrolling  Command     PWMLED41S0E15D4True

PWMLED”Address” S[Start channel] E[End channel] D[Delay / Timing] [True/False]

Address 41, 42,43,44

Start channel & End channel   0 ~ 15    16 channel

D   1,2,3,4,5    (1 ~ 100) Delay Timing

LED Brightness control Command

PWMLED “Address” “B” “0 ~ 1000“

PWMLED41B1000

Stop command

“PWMLED41STOP”

四、範例程式下載

servo-40.py

servo-41.py

pwm

pwm-v2  for Raspberry Pi V2 board

五、產品內容

1x Rs-Pi I2C 9685 -16 channel PWM &  23017-1  16 GPIO board

1x User Manual