MAX6955AAX Maxim Integrated Products, MAX6955AAX Datasheet - Page 18

• Manufacturer Part Number: MAX6955AAX
• Description: LED Drivers Integrated Circuits (ICs)
• Manufacturer: Maxim Integrated Products

Specifications of MAX6955AAX

• Number Of Digits: 16
• Number Of Segments: 128
• Low Level Output Current: 935000 uA
• High Level Output Current: 55000 uA
• Operating Supply Voltage: 2.7 V to 5.5 V
• Maximum Supply Current: 30000 uA
• Maximum Power Dissipation: 941 mW
• Maximum Operating Temperature: + 125 C
• Mounting Style: SMD/SMT
• Package / Case: SSOP-36
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

2-Wire Interfaced, 2.7V to 5.5V LED Display
Driver with I/O Expander and Key Scan
Figure 11. Key-Scanning Configuration
Figure 12. Key-Scan Timing Diagram
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LED OUTPUT 00
LED OUTPUT 01
LED OUTPUT 02
LED OUTPUT 03
LED OUTPUT 04
LED OUTPUT 05
LED OUTPUT 06
LED OUTPUT 07
V
CC
START
LED OUTPUT O0
LED OUTPUT O1
LED OUTPUT O2
LED OUTPUT O3
LED OUTPUT O4
LED OUTPUT O5
LED OUTPUT O6
LED OUTPUT O7
KEY_C (P2)
KEY_D (P3)
KEY_A (P0)
KEY_B (P1)
1.6ms MULTIPLEX CYCLE 1
IRQ (P4)
12.5µs TO 187.5µs DIGIT PERIOD
FIRST KEY TEST
PERIOD
MICROCONTROLLER INTERRUPT
END
SW A0
SW A1
SW A2
SW A3
SW A4
SW A5
SW A6
SW A7
12.8MS FIRST HALF KEY-SCAN CYCLE
1.6ms MULTIPLEX CYCLE 2
SW B0
SW B1
SW B2
SW B3
SW B4
SW B5
SW B6
SW B7
A 25.6MS KEY-SCAN CYCLE
1.6ms MULTIPLEX CYCLE 8
SW C0
SW C1
SW C2
SW C3
SW C4
SW C5
SW C6
SW C7
START
1.6ms MULTIPLEX CYCLE 1
SECOND KEY TEST
(DEBOUNCE)
PERIOD
12.8MS SECOND HALF KEY-SCAN CYCLE
SW D0
SW D1
SW D2
SW D3
SW D4
SW D5
SW D6
SW D7
END
INTERRUPT ASSERTED IF PERIOD
DEBOUNCE REGISTER UPDATED
START OF NEXT KEY-SCAN CYCLE
LED SEGMENT IS OPTIONAL AND
BASED ON APPLICATION.
1.6ms MULTIPLEX CYCLE 6
LED0
LED1
LED2
LED3
LED4
LED5