MAX7360 Maxim, MAX7360 Datasheet - Page 13

• Manufacturer Part Number: MAX7360
• Description: The MAX7360 I²C-interfaced peripheral provides microprocessors with management of up to 64 key switches, with an additional eight LED drivers/GPIOs that feature constant-current, PWM intensity control, and rotary switch control options
• Manufacturer: Maxim

4) Put the part into shutdown to cause all ports to fade
Each port has its own blink control settings through reg-
isters 0x58 to 0x5F (see Table 25 in the Register Tables
section). The blink period ranges from 0 (blink disabled)
to 4.096s. Settable blink duty cycles range from 6.25%
to 50%. All blink periods start at the same PWM cycle for
synchronized blinking between multiple ports.
Three possible sources generate INTI: I
GPIOs configured as inputs, and the rotary switch
(registers 0x48, 0x49, and 0x4A). Read the respective
data/status registers for each type of interrupt to clear
INTI. Set register 0x46 for rotary switch-based interrupts.
Figure 2. 2-Wire Serial Interface Timing Details
Figure 1. Rotary Switch Input Signal Timing
in automatically cancels that port’s fade and immedi-
ately output at its newly programmed intensity.
out. Changing an individual PWM intensity during
fade out automatically cancels that port’s fade and
immediately turns off.
I
2
Driver/GPIOs with Integrated ESD Protection
SDA
SCL
C-Interfaced Key-Switch Controller and LED
PORT7
PORT6
PORT7
PORT6
t
HD, STA
CONDITION
ROTARY SWITCH
START
______________________________________________________________________________________
DEBOUNCE
GPIO Port Interrupts (INTI)
t
LOW
t
R
t
HIGH
t
SU, DAT
INCREMENT
DECREMENT
t
F
t
HD, DAT
2
C timeout,
Blink
t
SU, STA
START CONDITION
Set registers 0x58 to 0x5F for individual GPI-based inter-
rupts. If multiple sources generate the interrupt, all the
related status registers must be read to clear INTI.
The MAX7360 can accept a 2-bit rotary switch inputs on
PORT6 and PORT7. Rotation of the switch in a clockwise
direction increments the count. Enable rotary switch
mode from the GPIO global configuration register (0x40).
Several settings for PORT6 and PORT7 occur during
rotary switch mode:
1) Each port has a 10FA pullup to V
2) Register 0x46 sets the debounce time.
3) A debounced rising edge on PORT6 while PORT7 is
4) A debounced rising edge on PORT6 while PORT7 is
For more details, see Figure 1.
Figure 2 shows the 2-wire serial interface timing details.
The MAX7360 operates as a slave that sends and
receives data through an I
face. The interface uses a serial-data line (SDA) and
a serial-clock line (SCL) to achieve bidirectional com-
munication between master(s) and slave(s). A master
(typically a microcontroller) initiates all data transfers to
and from the MAX7360 and generates the SCL clock that
synchronizes the data transfer.
The MAX7360’s SDA line operates as both an input and
an open-drain output. A pullup resistor, typically 4.7kI,
REPEATED
high decreases the count.
low increases the count.
t
t
HD, STA
R
t
SU, STO
t
t
2
F
F, TX
C-compatible 2-wire inter-
CONDITION
Serial Interface
STOP
Serial Addressing
CC
t
Rotary Switch
BUF
.
CONDITION
START
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