MAX6957AAX+T Maxim Integrated Products, MAX6957AAX+T Datasheet - Page 6

• Manufacturer Part Number: MAX6957AAX+T
• Description: IC DRVR DSPL LED 36-SSOP
• Manufacturer: Maxim Integrated Products

Specifications of MAX6957AAX+T

• Display Type: LED
• Configuration: 7, 16, 20 Segment
• Interface: 4-Wire Serial
• Current - Supply: 180µA
• Voltage - Supply: 2.5 V ~ 5.5 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 36-SSOP
• Number Of Segments: 28
• Low Level Output Current: 18 mA
• Operating Supply Voltage: 2.5 V to 5.5 V
• Maximum Supply Current: 230 uA
• Maximum Power Dissipation: 941 mW
• Maximum Operating Temperature: + 125 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Digits Or Characters: -
• Lead Free Status / Rohs Status: Details

The MAX6957 offers 20 or 28 I/O ports, depending on
package choice. These can be applied to a variety of
combinations of different display types, for example:
seven, 7-segment digits
requires two MAX6957s, with one digit being driven by
both devices, half by one MAX6957, half by the other
(digit 4 in this example). The two drivers are static, and
therefore do not need to be synchronized. The
MAX6957 sees CA digits as multiple discrete LEDs. To
simplify access to displays that overlap two MAX6957s,
the MAX6957 provides four virtual ports P0 through P3.
To update an overlapping digit, send the same code
twice as an eight-port write, once to P28 through P35 of
the first driver, and again to P0 through P7 of the sec-
4-Wire-Interfaced, 2.5V to 5.5V, 20-Port and
28-Port LED Display Driver and I/O Expander
Table 2. Port Configuration Matrix
Note: The logic is inverted between the two output modes; a high makes the output go low in LED segment driver mode (0x00) to
turn that segment on; in GPIO output mode (0x01), a high makes the output go high.
Table 1. Port Configuration Map
6
Port Configuration for P7, P6, P5, P4
Port Configuration for P11, P10, P9, P8
Port Configuration for P15, P14, P13, P12
Port Configuration for P19, P18, P17, P16
Port Configuration for P23, P22, P21, P20
Port Configuration for P27, P26, P25, P24
Port Configuration for P31, P30, P29, P28
Output
Output
MODE
Input
Input
_______________________________________________________________________________________
Register Control of I/O Ports and LEDs
LED Segment Driver
GPIO Input with
Without Pullup
GPIO Output
FUNCTION
GPIO Input
REGISTER
Across Multiple Drivers
(Figure 2). This example
input logic level
Register bit = 0
Register bit = 1
Register bit = 0
(0xA0–0xDF)
Register bit =
(0x20–0x5F)
REGISTER
PORT
CODE (HEX)
High impedance
Open-drain current sink, with sink
current (up to 24mA) determined
by the appropriate current register
Active-low logic output
Active-high logic output
Schmitt logic input
Schmitt logic input with pullup
ADDRESS
0x0A
0x0B
0x0C
0x0D
0x09
0x0E
0x0F
PIN BEHAVIOR
ond driver. The first driver ignores the last 4 bits and
the second driver ignores the first 4 bits.
Two addressing methods are available. Any single port
(bit) can be written (set/cleared) at once; or, any
sequence of eight ports can be written (set/cleared) in
any combination at once. There are no boundaries; it is
equally acceptable to write P0 through P7, P1 through
P8, or P31 through P38 (P32 through P38 are nonexis-
tent, so the instructions to these bits are ignored).
Using 8-bit control, a seven-segment digit with a deci-
mal point can be updated in a single byte-write, a 14-
segment digit with DP can be updated in two
byte-writes, and 16-segment digits with DP can be
updated in two byte-writes plus a bit write. Also, dis-
crete LEDs and GPIO port bits can be lit and controlled
individually without affecting other ports.
D7
P11
P15
P19
P23
P27
P31
P7
D6
D5
P10
P14
P18
P22
P26
P30
P6
REGISTER DATA
CODE (HEX)
0x09 to 0x0F
0x09 to 0x0F
0x09 to 0x0F
0x09 to 0x0F
ADDRESS
D4
D3
P13
P17
P21
P25
P29
P5
P9
UPPER
CONFIGURATION
D2
0
0
1
1
BIT PAIR
PORT
D1
LOWER
P12
P16
P20
P24
P28
P4
P8
0
1
0
1
D0