XRP7620 Exar Corporation, XRP7620 Datasheet - Page 9

• Manufacturer Part Number: XRP7620
• Description: 4-channel Adjustable Current I2c Controlled Led Driver
• Manufacturer: Exar Corporation

Addressing and Writing Data
To write data to the XRP7620 one of the
following two cycles must be followed:
Easy shutdown/startup sequence
[Slave Address with write bit][Data for Status]
Full shutdown/startup sequence
[Slave
Status][Data for LED1][Data for LED2][Data
for LED3][Data for LED4]
Addressing and Reading Data
To read data from the XRP7620 the following
data cycle must be obeyed:
[Slave
Status][Data for LED1][Data for LED2][Data
for LED3][Data for LED4]
S
The XRP7620 can be placed in shutdown mode
by holding both the SDA and SCL lines low for
a minimum of typically 90ms. This puts a zero
in bit 7 and bit 6 of the status register, which
in turn will reset all bits of all registers. After
any shutdown, the part can only be restarted
through the I
© 2009 Exar Corporation
HUTDOWN
Address
Address
O
2
C bus.
PTIONS
with
with
write
read
4
4
-
-
bit][Data
bit][Data
C
C
h
h
a
a
n
n
n
n
e
e
l
l
A
for
for
A
d
d
j
j
9/11
u
u
s
s
t
t
a
a
S
If an LED shorts to the extent that the LED pin
comes within 0.7V of V
turn off because the drive circuitry effectively
is in a dropout condition.
will vary with programmed LED current.
P
The maximum programmable current per LED
pin is 31.5mA. If a higher current is desired,
2, 3, or all 4 LED pins may be connected to
share current.
possible to program the channels to different
values to add up to the desired total, it is
recommended that paralleled channels be
programmed
b
b
HORTED
ARALELLING
l
l
e
e
C
C
u
u
r
r
r
r
LED
e
e
n
n
t
t
C
S
I
I
URRENT
2
2
to
C
C
Although it is technically
C
C
o
o
IN
n
the
n
t
t
S
the LED channel may
r
r
INKS
o
o
The exact voltage
l
l
l
l
e
e
same
d
d
X
X
L
L
R
R
E
E
D
D
P
P
Rev. 1.0.0
7
7
D
D
value.
6
6
r
r
i
i
2
v
2
v
e
e
0
0
r
r