LTC3219_15 Datasheet, PDF (13/20 Pages) Linear Technology – 250mA Universal Nine Channel LED Driver

LTC3219
OPERATION
Data Bytes
REG1 to REG9, Universal LED 6-bit linear DAC data with
blink/gradation.
Sub-Address 0001 TO 1001 per Sub-Address Table Above
ULED Mode Enable Bits
LED Current Data
MSB
LSB
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Normal
0
Blink Enabled
0
Gradation Enabled
1
GPO Mode
1
(Gradation/Blink/Dropout Off)
0
D5
D4
D3
D2
D1
D0
1
D5
D4
D3
D2
D1
D0
0
D5
D4
D3
D2
D1
D0
1
D5
D4
D3
D2
D1
D0
REG10, ENU
Setting bits D0 to D7 high selects the ULED outputs to be
controlled by ENU.
Register Sub-Address = 1010
MSB
Bit 7
Bit 6
Bit 5
ULED8
ULED7
ULED6
Bit 4
ULED5
Bit 3
ULED4
Bit 2
ULED3
Bit 1
ULED2
LSB
Bit 0
ULED1
REG11, Gradation and Blink Times
Setting bit D0 high selects ULED9 to be controlled by ENU,
Bits D1 to D4 control gradation and blink times.
The gradation ramp time is the time that the current ramps.
The gradation period is the total time that is required to start
and end a gradation timer.
Sub-Address = 1011
Blink Times and Period
D4
D3
On-Time
0
0
0.625s
0
1
0.156s
1
0
0.625s
1
1
0.156s
Period
1.25s
1.25s
2.5s
2.5s
Gradation Ramp Times and Period
D2
D1
Ramp Time Period
0
0
Disabled Disabled
0
1
0.24s
0.325s
1
0
0.48s
0.65s
1
1
0.96s
1.30s
ENU Select
D0
ULED9
3219fa
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