Datasheet PCA9685 (NXP) - 9

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NXP Semiconductors PCA9685 16-channel, 12-bit PWM Fm+ I2C-bus LED controller 7.1.4 Software Reset I2C-bus address
The address shown in Figure 5 is used when a reset of the PCA9685 needs to be performed by the master. The Software Reset address (SWRST Call) must be used with R/W = logic 0. If R/W = logic 1, the PCA9685 does not acknowledge the SWRST. See Section 7.6 “Software reset” for more detail. R/W 0 0 0 0 0 1 1 0 002aab416
Fig 5. Software Reset address Remark:
The Software Reset I2C-bus address is a reserved address and cannot be used as a regular I2C-bus slave address or as an LED All Call or LED Sub Call address.
7.2 Control register
Following the successful acknowledgement of the slave address, LED All Call address or LED Sub Call address, the bus master will send a byte to the PCA9685, which will be stored in the Control register. This register is used as a pointer to determine which register will be accessed. D7 D6 D5 D4 D3 D2 D1 D0 002aac826 reset state = 00h
Remark:
The Control register does not apply to the Software Reset I2C-bus address.
Fig 6. Control register
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 9 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