PCA9632 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved.
Product data sheet Rev. 5 — 27 July 2011 9 of 39
NXP Semiconductors
PCA9632
4-bit Fm+ I
2
C-bus low power LED driver
Remark: Other combinations not shown in Table 4 (AI[2:0] = 001, 010, and 011) are
reserved and must not be used for proper device operation.
AI[2:0] = 000 is used when the same register must be accessed several times during a
single I
2
C-bus communication, for example, changes the brightness of a single LED. Data
is overwritten each time the register is accessed during a write operation.
AI[2:0] = 100 is used when all the registers must be sequentially accessed, for example,
power-up programming.
AI[2:0] = 101 is used when the four LED drivers must be individually programmed with
different values during the same I
2
C-bus communication, for example, changing color
setting to another color setting.
AI[2:0] = 110 is used when the LED drivers must be globally programmed with different
settings during the same I
2
C-bus communication, for example, global brightness or
blinking change.
AI[2:0] = 111 is used when individual and global changes must be performed during the
same I
2
C-bus communication, for example, changing a color and global brightness at the
same time.
Only the 4 least significant bits D[3:0] are affected by the AI[2:0] bits.
When the Control register is written, the register entry point determined by D[3:0] is the
first register that will be addressed (read or write operation), and can be anywhere
between 0000 and 1100 (as defined in Table 5
). When AI[2] = 1, the Auto-Increment flag
is set and the rollover value at which the point where the register increment stops and
goes to the next one is determined by AI[2:0]. See Table 4
for rollover values. For
example, if the Control register = 1110 1000 (E8h), then the register addressing sequence
will be (in hex):
08 … 0C 00 … 07 02 … 07 02 … 07 02 … as long
as the master keeps sending or reading data.
Table 4. Auto-Increment options
AI2 AI1 AI0 Function
0 0 0 no Auto-Increment
1 0 0 Auto-Increment for all registers. D3, D2, D1, D0 roll over to ‘0000’ after
the last register (1100) is accessed.
1 0 1 Auto-Increment for Individual brightness registers only. D3, D2, D1, D0
roll over to ‘0010’ after the last register (0101) is accessed.
1 1 0 Auto-Increment for global control registers only. D3, D2, D1, D0 roll over
to ‘0110’ after the last register (0111) is accessed.
1 1 1 Auto-Increment for individual and global control registers only. D3, D2,
D1, D0 roll over to ‘0010’ after the last register (0111) is accessed.
