AK8456 Datasheet, PDF (21/32 Pages) Asahi Kasei Microsystems – 3 channel input 16bit 30MSPS Video ADC with LED driver

A/D ¹⁶ Digital ¹⁶
PGA
Gray
Code
[AK8456]
16bit
16
8

Upper 8bit
Lower 8bit
D7~D0
D15
G15
D14
G14
D13
G13
D12
Gray code conversion G12
D11
G11
D10
G10
D9
D8 ^{Forward Backward}
G9
G8 ^{Forward Backward}
D7
D15 D7
G7
G15 G7
D6
D14 D6
G6
G14 G6
D5
D13 D5
G5
G13 G5
D4
D12 D4
G4
G12 G4
D3
D11 D3
G3
G11 G3
D2
D10 D2
G2
G10 G2
D1
D9 D1
G1
G9 G1
D0
D8 D0
G0
G8 G0
Normal
Gray Code
Fig.23 Output format
 LED Driver
LED Driver controls LED current RGB independently. LED must be connected as anode
common. If LEDEN_R/G/B are high level, LED current are driven. If LEDEN_R/G/B are
low level, LED current are stopped. LEDEN_R/G/B are synchronized once by SHD
internally. Therefore if SHD is not input, LEDEN_R/G/B are not effective.
 LED Current Adjustment
The LED current can be adjusted in increments of 8.4mA to 67.2mA from 8.4mA channel
independently.
 LED Current Limit
AK8456 LED driver current limitation is 100.8mA (total:150% setting). With the
combination with “LEDEN_R/G/B pin logic” and LED drive current setting register value,
in case of the combination that the total of the current amount to flow through at the same
time exceeds 150%(100.8 mA), the LED drive current doesn't flow. For example, when
making "LEDEN_R/G/B" active at the same time and when the total of the LED drive
current set value exceeds 150%(100.8 mA), the LED drive current doesn't flow. On the other
hand, when making "LEDEN_R/G/B" active individually, the current flows.
014002433-E-00
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2014/06