Datasheet

MAX7314
Functional Overview
The MAX7314 is a general-purpose input/output (GPIO)
peripheral that provides 16 I/O ports, P0–P15, con-
trolled through an I
2
C-compatible serial interface. A
17th output-only port, INT/O16, can be configured as
an interrupt output or as a general-purpose output port.
All output ports sink loads up to 50mA connected to
external supplies up to 5.5V, independent of the
MAX7314’s supply voltage. The MAX7314 is rated for a
ground current of 350mA, allowing all 17 outputs to sink
20mA at the same time. Figure 1 shows the output
structure of the MAX7314. The ports default to inputs on
power-up.
18-Port GPIO with LED Intensity Control,
Interrupt, and Hot-Insertion Protection
6 _______________________________________________________________________________________
Pin Description
Figure 1. Simplified Schematic of I/O Ports
D
C
K
Q
Q
FF
DATA FROM
SHIFT REGISTER
DATA FROM
SHIFT REGISTER
WRITE
CONFIGURATION
PULSE
WRITE PULSE
READ PULSE
CONFIGURATION
REGISTER
D
C
K
Q
Q
FF
INPUT PORT
REGISTER
D
C
K
Q
Q
FF
OUTPUT
PORT
REGISTER
OUTPUT PORT
REGISTER DATA
I/O PIN
Q2
GND
INPUT PORT
REGISTER DATA
TO INT
PIN
QSOP QFN
NAME FUNCTION
122INT/O16
Output Port. Open-drain output rated at 7V, 50mA. Configurable as interrupt
output or general-purpose output.
223RST
Reset Input. Active low clears the 2-wire interface and puts the device in the
same condition as power-up reset.
3 24 AD0
Address Input. Sets device slave address. Connect to either GND, V+, SCL,
or SDA to give four logic combinations. See Table 1.
4–11, 13–20 1–8, 10–17 P0–P15 Input/Output Ports. P0–P15 are open-drain I/Os rated at 5.5V, 50mA.
12 9 GND Ground. Do not sink more than 350mA into the GND pin.
21 18 BLINK Input Port Configurable as Blink Control or General-Purpose Input
22 19 SCL I
2
C-Compatible Serial Clock Input
23 20 SDA I
2
C-Compatible Serial Data I/O
24 21 V+
Positive Supply Voltage. Bypass V+ to GND with a 0.047µF ceramic
capacitor.
— PAD Exposed Pad Exposed Pad on Package Underside. Connect to GND.