- 8 × 8 standard keys
- 8 special function keys (SF keys) provide the largest matrix keyboard with a total of 72 keys
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ACCESS.bus (I 2 C compatible) communication interface to the host
- 4 universal host programmable I/O pins with two selectable external interrupts (slow)
- 15 byte FIFO buffer to store key press and key release events
- Error control for error reporting (FIFO overflow, overflow keyboard, command invalid)
- Host programmable PWM
- Host programmable activity time and bounce time
illustrate
The LM8333 Mobile I/O Assistant offloads the burden of scanning the keyboard from the host while providing extremely low power consumption in both work and standby modes. It supports keyboard matrix sizes of 8 × 8 (plus 8 additional special function keys) for portable applications such as mobile phones, PDAs, games, and other handheld applications.
Keystroke and release events are encoded into a byte format and loaded into the FIFO buffer for retrieval by the host processor. Interrupt Output (IRQ) is used for signals such as keypad activity, state changes in one or two common I/O pins for interrupting functions, or events for error conditions. Interrupt and error codes are available to the host by reading the dedicated registers.
4 universal I/O pins, two of which have interrupt capability. A host-based programmable internal timer pulse width modulation output is also available, and the PWM function is not required to be used as a universal output.
To reduce power consumption, the LM8333 automatically enters low-power standby mode with no keyboard, I/O, or host activity.
The device is available in a 32-pin leadless lead-frame package (LLP) with a 49-pin microarray. These two chip-scale packages.
apply
- mobile phone
- Personal digital assistants (PDAs, etc.)
- Smart handheld devices
- Personal media player
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