MAX7313AEG Maxim Integrated Products, MAX7313AEG Datasheet - Page 20

• Manufacturer Part Number: MAX7313AEG
• Description: I/O Expanders, Repeaters & Hubs 16-Bit I/O Port Expander
• Manufacturer: Maxim Integrated Products

Specifications of MAX7313AEG

• Package / Case: QSOP-24
• Mounting Style: SMD/SMT
• Lead Free Status / Rohs Status: No

When blink is disabled (Table 7), the blink phase 0 reg-
isters specify each output’s logic level during the PWM
on-time (Table 8). The effect of setting an output’s blink
phase 0 register bit to 0 or 1 is shown in Table 11. With
its output bit set to zero, an LED can be controlled with
16 intensity settings from 1/16th duty through fully on,
but cannot be turned fully off using the PWM intensity
control. With its output bit set to 1, an LED can be con-
trolled with 16 intensity settings from fully off through
15/16th duty.
When blink is enabled (Table 7), the blink phase 0 regis-
ters and blink phase 1 registers specify each output’s
logic level during the PWM on-time during the respective
blink phases (Tables 8 and 9). The effect of setting an
output’s blink phase x register bit to 0 or 1 is shown in
Table 12. LEDs can be flipped between either directly on
and off, or between a variety of high/low PWM intensities.
16-Port I/O Expander with LED Intensity
Control, Interrupt, and Hot-Insertion Protection
Table 12. PWM Intensity Settings (Blink Enabled)
20
INTENSITY
GLOBAL)
SETTING
OUTPUT
Using PWM Intensity Controls with Blink Disabled
Using PWM Intensity Controls with Blink Enabled
(OR
0xA
0xB
0xC
0xD
0x0
0x1
0x2
0x3
0x4
0x5
0x6
0x7
0x8
0x9
0xE
0xF
______________________________________________________________________________________
Static low
PWM DUTY CYCLE
REGISTER BIT = 0
10/16
11/16
12/16
13/16
14/16
15/16
LOW
TIME
1/16
2/16
3/16
4/16
5/16
6/16
7/16
8/16
9/16
OUTPUT BLINK
PHASE X
Static low
HIGH
15/16
14/16
13/16
12/16
11/16
10/16
TIME
9/16
8/16
7/16
6/16
5/16
4/16
3/16
2/16
1/16
impedance
Static high
PWM DUTY CYCLE
REGISTER BIT = 1
15/16
14/16
13/16
12/16
11/16
10/16
LOW
TIME
9/16
8/16
7/16
6/16
5/16
4/16
3/16
2/16
1/16
OUTPUT BLINK
PHASE X
impedance
Static high
HIGH
10/16
11/16
12/16
13/16
14/16
15/16
TIME
1/16
2/16
3/16
4/16
5/16
6/16
7/16
8/16
9/16
P hase 0: LE D on at hi g h i ntensi ty
P hase 1: LE D on at hi g h i ntensi ty
P hase 1: LE D on at l ow i ntensi ty
Phase 0: LED on continuously
Phase 1: LED off continuously
P hase 0: LE D on at l ow i ntensi ty
The 4 bits used for output O16’s PWM individual inten-
sity setting also double as the global intensity control
(Table 13). Global intensity simplifies the PWM settings
when the application requires them all to be the same,
such as for backlight applications, by replacing the 17
individual settings with 1 setting. Global intensity is
enabled with the Global Intensity flag G in the configu-
ration register (Table 4). When global PWM control is
used, the 4 bits of master intensity and 4 bits of global
intensity effectively combine to provide an 8 bit, 240-
step intensity control applying to all outputs.
It is not possible to apply global PWM control to a sub-
set of the ports, and use the others as logic outputs. To
mix static logic outputs and PWM outputs, individual
PWM control must be selected (Table 10).
REGISTER BIT = 0
REGISTER BIT = 1
BLINK PHASE 0
BLINK PHASE 1
Output is half intensity during both blink phases
EXAMPLES OF LED BLINK BEHAVIOR
(LED IS ON WHEN OUTPUT IS LOW)
Global/O16 Intensity Control
P hase 0: LE D on at hi g h i ntensi ty
P hase 1: LE D on at l ow i ntensi ty
P hase 1: LE D on at hi g h i ntensi ty
Phase 0: LED off continuously
Phase 1: LED on continuously
P hase 0: LE D on at l ow i ntensi ty
REGISTER BIT = 1
REGISTER BIT = 0
BLINK PHASE 0
BLINK PHASE 1