MAX7315 Maxim, MAX7315 Datasheet - Page 6

• Manufacturer Part Number: MAX7315
• Description: The MAX7315 I²C-/SMBus™-compatible serial interfaced peripheral provides microprocessors with 8 I/O ports
• Manufacturer: Maxim

8-Port I/O Expander with LED Intensity
Control, Interrupt, and Hot-Insertion Protection
The MAX7315 is a general-purpose input/output (GPIO)
peripheral that provides eight I/O ports, P0–P7, con-
trolled through an I
output-only port, INT/O8, can be configured as an inter-
rupt output or as a general-purpose output port. All out-
put ports sink loads up to 50mA connected to external
supplies up to 5.5V, independent of the MAX7315’s
Figure 1. Simplified Schematic of I/O Ports
6
QSOP/TSSOP
_______________________________________________________________________________________
4–7, 9–12
1, 2, 3
13
14
15
16
—
8
PIN
2
C-compatible serial interface. A 9th
2–5, 7–10
15, 16, 1
Functional Overview
QFN
PAD
11
12
13
14
6
CONFIGURATION
SHIFT REGISTER
SHIFT REGISTER
WRITE PULSE
READ PULSE
DATA FROM
DATA FROM
PULSE
WRITE
Exposed pad Exposed Pad on Package Underside. Connect to GND.
AD0, AD1,
INT/O8
CONFIGURATION
NAME
P0–P7
GND
SDA
AD2
SCL
V+
REGISTER
D
C
K
FF
Q
Q
Address Inputs. Sets device slave address. Connect to either GND, V+,
SCL, or SDA to give 64 logic combinations. See Table 1.
Input/Output Ports. P0–P7 are open-drain I/Os rated at 5.5V, 50mA.
Ground. Do not sink more than 190mA into the GND pin.
Output Port. Open-drain output rated at 7.0V, 50mA. Configurable as
interrupt output or general-purpose output.
I
I
Positive Supply Voltage. Bypass V+ to GND with a 0.047µF ceramic
capacitor
2
2
REGISTER
C-Compatible Serial Clock Input
C-Compatible Serial Data I/O
OUTPUT
D
C
PORT
K
FF
INPUT PORT
REGISTER
D
C
Q
Q
K
FF
Q
Q
supply voltage. The MAX7315 is rated for a ground cur-
rent of 190mA, allowing all nine outputs to sink 20mA at
the same time. Figure 1 shows the output structure of
the MAX7315. The ports default to inputs on power-up.
An input ports register reflects the incoming logic levels
of the port pins, regardless of whether the pin is
defined as an input or an output. Reading the input
Port Inputs and Transition Detection
Q2
FUNCTION
OUTPUT PORT
REGISTER DATA
I/O PIN
GND
INPUT PORT
REGISTER DATA
TO INT
Pin Description