PCA9624 All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2016. All rights reserved.
Product data sheet Rev. 4.1 — 18 January 2016 6 of 40
NXP Semiconductors
PCA9624
8-bit Fm+ I
2
C-bus 100 mA 40 V LED driver
[1] HVQFN24 package supply ground is connected to both V
SS
pins and exposed center pad. V
SS
pins must
be connected to supply ground for proper device operation. For enhanced thermal, electrical, and board
level performance, the exposed pad must be soldered to the board using a corresponding thermal pad on
the board and for proper heat conduction through the board, thermal vias must be incorporated in the PCB
in the thermal pad region.
7. Functional description
Refer to Figure 1 “Block diagram of PCA9624”.
7.1 Device addresses
Following a START condition, the bus master must output the address of the slave it is
accessing.
There are a maximum of 128 possible programmable addresses using the 7 hardware
address pins. Two of these addresses, Software Reset and LED All Call, cannot be used
because their default power-up state is ON, leaving a maximum of 126 addresses. Using
other reserved addresses, as well as any other Sub Call address, reduces the total
number of possible addresses even further.
7.1.1 Regular I
2
C-bus slave address
The I
2
C-bus slave address of the PCA9624 is shown in Figure 4. To conserve power, no
internal pull-up resistors are incorporated on the hardware selectable address pins and
they must be pulled HIGH or LOW.
Remark: Using reserved I
2
C-bus addresses interferes with other devices, but only if the
devices are on the bus and/or the bus is open to other I
2
C-bus systems at some later
date. In a closed system where the designer controls the address assignment these
addresses can be used since the PCA9624 treats them like any other address. The
LED All Call, Software Rest and PCA9564 or PCA9665 slave address (if on the bus) can
never be used for individual device addresses.
• PCA9624 LED All Call address (1110 000) and Software Reset (0000 0110) which are
active on start-up
• PCA9564 (0000 000) or PCA9665 (1110 000) slave address which is active on
start-up
• ‘reserved for future use’ I
2
C-bus addresses (0000 011, 1111 1XX)
• slave devices that use the 10-bit addressing scheme (1111 0XX)
• slave devices that are designed to respond to the General Call address (0000 000)
• High-speed mode (Hs-mode) master code (0000 1XX)
Fig 4. Slave address
R/W
002aab319
A6 A5 A4 A3 A2 A1 A0
hardware selectable
slave address