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AS3820

16-Channel White LED Controller for LCD Backlight

Rev. 1.1

Datasheet

www.dialog-semiconductor.com

36 of 52

05-Feb-2019

VOUT =

(1+_______)xV

SENSE + R1 x “idac_fbx_counter” x 1μA

Example: VoutMIN = 60V, VoutMAX = 80V, VSENSE = 1.25V

(VoutMAX – VoutMIN)

(80V – 60V)

R1 = _________________ = ____________ = 78kW

255μA

78kW

R2 = _______________ = _______________ = 1.66kW

VoutMIN

60V

(__________1) (_______1)

VSENSE

1.25V

8.7 GPIO

The two pins DCDCEN and Mode3D can be used to change the configuration of a DC-DC controller. These pins can

also be used as general purpose input/output pins which can be configured as high impedance input, Push-Pull output

or Open drain output. Also the output pin xFAULT can be configured.

Figure 8.16 : GPIO

8.8 SPI Interface

For the data transfer a serial peripheral interface (SPI) is used. The SPI is configured to work only as SPI slave. If

more than one driver is connected to a SPI master, they can be connected in a “Daisy Chain”-structure or a parallel

structure.

8.8.1 SPI Daisy Chain Structure

All SPI slaves share the same clock (SCLK) and chip select (xCS) signal. In that configuration all devices can

be treated as one big shift register. The devices are automatically enumerated as described in the next section.

AS3820 데이터시트(PDF) 36 Page - Dialog Semiconductor