I

The chip address for LM27965 is 0110110, or 36h.

INTERNAL REGISTERS OF LM27965

Register

Internal Hex

Address

Power On

Value

General Purpose

Register

10h

0010 0000

Bank A Brightness

Control Register

A0h

1110 0000

Bank B

Brightness Control

Register

B0h

1110 0000

Bank C

Brightness Control

Register

C0h

1111 1100

Note: ENA: Enables DxA LED drivers (Main Display)

ENB: Enables DxB LED drivers (Aux Lighting)

ENC: Enables D1C LED driver (Indicator Lighting)

EN5A: Enables D5A LED voltage sense

EN3B: Enables D3B LED driver and voltage sense

Note: DxA4-DxA0: Sets Brightness for DxA pins (BankA). 11111=Fullscale

DxB4-DxB0: Sets Brightness for DxB pins (BankB). 11111=Fullscale

Bit7 to Bit 5: Not Used

DxC1-DxC0: Sets Brightness for DxC pin. 11 = Fullscale

Bit7 to Bit2:Not Used

Full-Scale Current set externally by the following equation:

20155012

FIGURE 3. Write Cycle

w = write (SDIO = "0")

r = read (SDIO = "1")

ack = acknowledge (SDIO pulled down by either master or slave)

id = chip address, 36h for LM27965

20155009

FIGURE 4. Chip Address

20155008

FIGURE 5. General Purpose Register Description

Internal Hex Address: 10h

20155005

20155006

20155007

FIGURE 6. Brightness Control Register Description

Internal Hex Address: 0xA0 (BankA), 0xB0 (BankB),

0xC0 (BankC)

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