PCA9685BS NXP [NXP Semiconductors], PCA9685BS Datasheet - Page 6

• Manufacturer Part Number: PCA9685BS
• Description: 16-channel, 12-bit PWM Fm+ I2C-bus LED controller
• Manufacturer: NXP [NXP Semiconductors]

NXP Semiconductors
7. Functional description
PCA9685_2
Product data sheet
7.1.1 Regular I
7.1 Device addresses
Table 2.
[1]
[2]
Refer to
Following a START condition, the bus master must output the address of the slave it is
accessing.
There are a maximum of 64 possible programmable addresses using the 6 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 62 addresses. Using
other reserved addresses, as well as any other subcall address, will reduce the total
number of possible addresses even further.
The I
internal pull-up resistors are incorporated on the hardware selectable address pins and
they must be pulled HIGH or LOW.
Remark: Using reserved I
devices are on the bus and/or the bus will be open to other I
date. In a closed system where the designer controls the address assignment these
addresses can be used since the PCA9685 treats them like any other address. The
LED All Call, Software Reset and PCA9564 or PCA9665 slave address (if on the bus) can
never be used for individual device addresses.
Symbol
LED12
LED13
LED14
LED15
OE
A5
EXTCLK
SCL
SDA
V
•
DD
HVQFN28 package die supply ground is connected to both V
be connected to supply ground for proper device operation. For enhanced thermal, electrical, and board
level performance, the exposed pad needs to be soldered to the board using a corresponding thermal pad
on the board and for proper heat conduction through the board, thermal vias need to be incorporated in the
PCB in the thermal pad region.
This pin must be grounded when this feature is not used.
PCA9685 LED All Call address (1110 000) and Software Reset (0000 0110) which
are active on start-up
2
C-bus slave address of the PCA9685 is shown in
Figure 1 “Block diagram of
2
Pin description
C-bus slave address
Pin
TSSOP28
19
20
21
22
23
24
25
26
27
28
Rev. 02 — 16 July 2009
HVQFN28
16
17
18
19
20
21
22
23
24
25
2
…continued
C-bus addresses will interfere with other devices, but only if the
16-channel, 12-bit PWM Fm+ I
Type
O
O
O
O
I
I
I
I
I/O
power supply
PCA9685”.
Description
LED driver 12
LED driver 13
LED driver 14
LED driver 15
active LOW output enable
address input 5
external clock input
serial clock line
serial data line
supply voltage
SS
pin and exposed center pad. V
Figure
2
C-bus systems at some later
4. To conserve power, no
2
C-bus LED controller
[2]
PCA9685
© NXP B.V. 2009. All rights reserved.
SS
pin must
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