MAX1234ETI+T Maxim Integrated Products, MAX1234ETI+T Datasheet - Page 40

• Manufacturer Part Number: MAX1234ETI+T
• Description: IC CNTRLR TOUCH 28-TQFN
• Manufacturer: Maxim Integrated Products
• Type: Resistiver

Specifications of MAX1234ETI+T

• Touch Panel Interface: 4-Wire
• Number Of Inputs/keys: 1, 4 x 4 Keypad
• Resolution (bits): 8, 10, 12 b
• Data Interface: MICROWIRE™, QSPI™, Serial, SPI™
• Data Rate/sampling Rate (sps, Bps): 50k
• Voltage Reference: Internal
• Voltage - Supply: 4.75 V ~ 5.25 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 28-TQFN Exposed Pad
• Applications: *
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

±15kV ESD-Protected Touch-Screen
Controllers Include DAC and Keypad Controller
Figure 25. Key-Press-Initiated Debounce Scan
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YES
KEY-PRESS-INITIATED DEBOUNCE SCAN
SCAN AND DEBOUNCE KEYS
RESULTS IN REGISTER
STORE KEYPAD SCAN
UNREAD DEBOUNCE
RESET KEYIRQ HIGH
IS KEYSTS1 = 1?
SET BUSY HIGH
SET BUSY LOW
START CLOCK
KEYIRQ LOW
ARE THERE
RESULTS?
KEYPAD
TOUCH
DONE
SET
NO
YES
NO
GO TO HOST-INITIATED
DEBOUNCE SCAN
Figure 26. Host-Initiated Debounce Scan
YES
HOST-INITIATED DEBOUNCE SCAN
SCAN AND DEBOUNCE KEYS
RESULTS IN REGISTER
STORE KEYPAD SCAN
UNREAD DEBOUNCE
CONTROL REGISTER
RESET KEYIRQ HIGH
IS KEYSTS1 = 1?
SET BUSY HIGH
SET BUSY LOW
HOST WRITES
START CLOCK
KEYIRQ LOW
ARE THERE
RESULTS?
KEYPAD
TOUCH
DONE
ADC
SET
NO
NO
YES
GO TO KEY-PRESS-INITIATED
DEBOUNCE SCAN