ROHM BU8310AK

Communication ICs
Panel interface
BU8310AK / BU8311KS / BU8313K
The BU8310AK, BU8311KS, and BU8313K are large-scale integrated circuits for telephones, which enable a serial input / output interface between the key input required for telephone panel boards and LED control functions. They reduce
the number of wiring harnesses needed between the main board in the telephone and the panel board, and take some
of the processing load off the main CPU.
Applications
Telephones and cordless telephones
Features
1) Keypad matrix interface
1 Key input is output as 16-bit serial data.
2 Internal chattering prevention circuit built into the
key input circuit.
2) LED interface
1 LED control commands input as 16-bit serial data.
2 Bits with a pattern generator and pattern register
can be assigned three independent flashing patterns in addition to being lighted or off.
3 Power consumption can be reduced using RST
pin input.
4 LED on and off control can be initiated using ENA
pin input or by commands setting all LEDs valid or
invalid.
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Communication ICs
Block diagram
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BU8310AK / BU8311KS / BU8313K
Communication ICs
BU8310AK / BU8311KS / BU8313K
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Communication ICs
FAbsolute maximum ratings (Ta = 25_C)
FRecommended operating conditions
FPin descriptions
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BU8310AK / BU8311KS / BU8313K
Communication ICs
BU8310AK / BU8311KS / BU8313K
Input / output circuits
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Communication ICs
BU8310AK / BU8311KS / BU8313K
FElectrical characteristics
DC characteristics (unless otherwise noted,Ta = 25_C, VDD = 3 5V)
AC characteristics (unless otherwise noted, Ta = 25_C, VDD = 3 5V)
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Communication ICs
BU8310AK / BU8311KS / BU8313K
Serial data output timing
Serial data input timing
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Communication ICs
BU8310AK / BU8311KS / BU8313K
Data formats (Serial data is input and output with the MSB coming first.)
(1) Reading key data
(2) Data register write command
(3) Pattern register write command
(4) All LEDs valid command
(5) All LEDs invalid command
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Communication ICs
BU8310AK / BU8311KS / BU8313K
(6) Register reset command
Entering data settings
(1) Setting operands
(2) Setting the blink cycle
Driver internal equivalent circuit (for 1 bit)
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Communication ICs
Recommended method for inputting / outputting data
(1) Serial output of key data
(2) Serial input of LED control commands
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Communication ICs
Operation notes
(1) Serial output of key data when several keys are
pressed at the same is as shown below.
BU8310AK / BU8311KS / BU8313K
(3) When the power supply is turned on, the internal registers should be reset using either RST pin input or the
register reset command.
(4) If the RST pin is set to LOW or the register reset command is executed while data is being output, the SDO
output logic is not reset.
(5) If the D, P, and Q registers are rewritten, all eight bits
should be written, and not just the pertinent bits.
The key data when 32 and 43 are pressed at the same
time will be the same as the key data when 33 and 42
are pressed at the same time.
(2) Pressing different keys
When a different key is pressed from the one already
pressed, KD is turned temporarily to provide notification
of the change.
(6) Operation states in response to RST, KSCN and ENA pin input
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Communication ICs
External dimensions (Units: mm)
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BU8310AK / BU8311KS / BU8313K