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KTZ8866

January 2022 - Revision 04b

Page 27 of 37

Company Confidential

Table 7. BL_CFG1 Register

ADDRESS

MODE

RESET VALUE: 0xFA

0x02

R/W

BIT

NAME

POR

DESCRIPTION

7:5

BL_OVP

111

Backlight OVP

000: 21.4V

001: 26.4V

010: 31.5V

011: 36.5V

100: 23.9V

101: 29.0V

110: 34.0V

111: 40.0V (Default)

4

OVP_MODE

1

0: OVP is report only

1: OVP will turn off the fault string that cause OVP event. (Default)

3

BLED_MAP

1

0: Exponential

1: Linear (Default)

2

PWM_CONFIG

0

0: Active high (Default)

1: Active low

1

RAMP_SHAPE

1

0: Exponential

1: Linear (Default)

0

PWM_ENABLE

0

0: PWM disabled (Default)

1: PWM enabled

Note: When Backlight Current Mapping setting is changed, the LED current change will not take effect until Register 0x05 is programmed.

Table 8. BL_CFG2 Register

ADDRESS

MODE

RESET VALUE: 0x8D

0x03

R/W

BIT

NAME

POR

DESCRIPTION

7

RSVD

1

Reserved (Must be 1)

6:3

LED CURRENT

RAMP

0001

Controls backlight LED ramping time. The transient time is a constant time that

the backlight takes to transition from an existing programmed code to a new

programmed code.

0000 : 1µs

0001 : 2ms(Default)

0010 : 4ms

0011 : 8ms

0100 : 16ms

0101 : 32ms

0110 : 64ms

0111 : 128ms

1000 : 192ms

1001 : 256ms

1010 : 320ms

1011 : 384ms

1100 : 448ms

1101 : 512ms

1110 : 576ms

1111 : 640ms

2:0

PWM_HYST

101

Sets the minimum change in PWM input duty cycle that results in a change of

backlight LED brightness level

000 : 0 LSB

001: 2 LSBs

010: 4 LSBs

011: 6 LSBs

100: 8 LSBs

101: 10 LSBs(Default)

110: 12 LSBs

111: 14 LSBs

1. For LED CURRENT RAMP Time in the table, all the ramp times are fixed when current ramps from one level to the other except "0000" setting. For

"0000" setting, the ramp slope is 1µs/step, the final ramp time is proportional to the 11-bit current steps.