MAX6967 MAXIM [Maxim Integrated Products], MAX6967 Datasheet - Page 22

• Manufacturer Part Number: MAX6967
• Description: 10-Port Constant-Current LED Drivers and I/O Expanders with PWM Intensity Control
• Manufacturer: MAXIM [Maxim Integrated Products]

Alternatively, the MAX6966/MAX6967s can be daisy-
chained by connecting the DOUT of one device to the
DIN of the next, and driving SCLK and CS lines in paral-
lel (Figure 9). This connection allows the MAX6966/
MAX6967s to be read. Data at DIN propagates through
the internal shift registers and appears at DOUT 15.5
clock cycles later, clocked out on the falling edge of
SCLK. When sending commands to daisy-chained
MAX6966/MAX6967s, all devices are accessed at the
same time. An access requires (16 x n) clock cycles,
where n is the number of MAX6966/MAX6967s connect-
10-Port Constant-Current LED Drivers and I/O
Expanders with PWM Intensity Control
Figure 9. MAX6966/MAX6967 Daisy-Chain Connection
Figure 10. Timing Diagram
22
______________________________________________________________________________________
DOUT
SCLK
DIN
CS
µC
MOSI
SCLK
MISO
CS
t
CSS
t
DS
D15
t
DIN
CS
SCLK
DH
MAX6966
MAX6967
t
CL
DOUT
D14
t
CH
ed together. For daisy-chaining to work, DOUT/OSC
must be configured as DOUT by clearing configuration
register bit D7 to zero (Table 4). Note that the MAX6966
powers up with DOUT/OSC configured as DOUT output
by default, while the MAX6967 powers up with
DOUT/OSC configured as OSC input by default. The
serial-interface speed (maximum SCLK) is limited to
17.5MHz when multiple devices are daisy-chained due
to the DOUT propagation delay and DIN setup time.
Figure 10 is the timing diagram.
DIN
CS
SCLK
D1
MAX6966
MAX6967
t
CP
t
DO
DOUT
D0
t
CSH
t
CSW
SCLK
CS
DIN
MAX6966
MAX6967
D15
DOUT