Datasheet PCA9685 (NXP) - 5

NXP Semiconductors PCA9685 16-channel, 12-bit PWM Fm+ I2C-bus LED controller 5. Block diagram
A0 A1 A2 A3 A4 A5
PCA9685
SCL INPUT FILTER SDA I2C-BUS CONTROL POWER-ON VDD RESET VDD VSS LED STATE SELECT REGISTER PWM REGISTER X PRESCALE BRIGHTNESS LEDn CONTROL 25 MHz OSCILLATOR CLOCK MUX/ SWITCH CONTROL EXTCLK '0' – permanently OFF '1' – permanently ON OE 002aac824
Remark:
Only one LED output shown for clarity.
Fig 1. Block diagram of PCA9685
PCA9685 All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2015. All rights reserved.
Product data sheet Rev. 4 — 16 April 2015 5 of 52
Document Outline 1. General description 2. Features and benefits 3. Applications 4. Ordering information 4.1 Ordering options 5. Block diagram 6. Pinning information 6.1 Pinning 6.2 Pin description 7. Functional description 7.1 Device addresses 7.1.1 Regular I2C-bus slave address 7.1.2 LED All Call I2C-bus address 7.1.3 LED Sub Call I2C-bus addresses 7.1.4 Software Reset I2C-bus address 7.2 Control register 7.3 Register definitions 7.3.1 Mode register 1, MODE1 7.3.1.1 Restart mode 7.3.2 Mode register 2, MODE2 7.3.3 LED output and PWM control 7.3.4 ALL_LED_ON and ALL_LED_OFF control 7.3.5 PWM frequency PRE_SCALE 7.3.6 SUBADR1 to SUBADR3, I2C-bus subaddress 1 to 3 7.3.7 ALLCALLADR, LED All Call I2C-bus address 7.4 Active LOW output enable input 7.5 Power-on reset 7.6 Software reset 7.7 Using the PCA9685 with and without external drivers 8. Characteristics of the I2C-bus 8.1 Bit transfer 8.1.1 START and STOP conditions 8.2 System configuration 8.3 Acknowledge 9. Bus transactions 10. Application design-in information 11. Limiting values 12. Static characteristics 13. Dynamic characteristics 14. Test information 15. Package outline 16. Handling information 17. Soldering of SMD packages 17.1 Introduction to soldering 17.2 Wave and reflow soldering 17.3 Wave soldering 17.4 Reflow soldering 18. Abbreviations 19. Revision history 20. Legal information 20.1 Data sheet status 20.2 Definitions 20.3 Disclaimers 20.4 Trademarks 21. Contact information 22. Contents