Rainbow Electronics MAX5970 User Manual
Page 36
0V to 16V, Dual Hot-Swap Controller with 10-Bit
Current and Voltage Monitor and 4 LED Drivers
MAX5970
36 _____________________________________________________________________________________
Table 53. LED State Register
Table 54. MAX5970 Slave Address Settings
Table 53 shows LED State register. The LED State regis-
ter is a read-only register. When the LEDs are disabled,
the pins are configured as GPIOs. Applying an external
voltage below 0.4V sets the GPIOs low and, applying an
external voltage above 1.4V, sets the GPIOs high.
I
2
C Serial Interface
The MAX5970 features an I
2
C serial interface consist-
ing of a serial-data line (SDA) and a serial-clock line
(SCL). SDA and SCL allow bidirectional communication
between the MAX5970 and the master device at clock
rates from up to 400kHz. The I
2
C bus can have several
devices (e.g., more than one MAX5970, or other I
2
C
devices in addition to the MAX5970) attached simultane-
ously. The A0 and A1 inputs set one of nine possible I
2
C
addresses (see Table 54).
Description:
LED State register
Register Title:
LED_State
Register Address:
0x45
R
R
R
R
R
R
R
R
RESET
VALUE
—
—
—
—
LED4
Voltage
LED3
Voltage
LED2
Voltage
LED1
Voltage
—
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
ADDRESS INPUT
STATE
I
2
C ADDRESS BITS
A1
A0
ADDR 7
ADDR 6
ADDR 5
ADDR 4
ADDR 3
ADDR 2
ADDR 1
ADDR 0
Low
Low
0
1
1
1
0
1
0
R/W
Low
High
0
1
1
1
0
0
1
R/W
Low
Open
0
1
1
1
0
0
0
R/W
High
Low
0
1
1
0
1
1
0
R/W
High
High
0
1
1
0
1
0
1
R/W
High
Open
0
1
1
0
1
0
0
R/W
Open
Low
0
1
1
0
0
1
0
R/W
Open
High
0
1
1
0
0
0
1
R/W
Open
Open
0
1
1
0
0
0
0
R/W