LM4970 Datasheet, PDF (9/19 Pages) National Semiconductor (TI) – Audio Synchronized Color LED Driver

LM4970
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Data Bit
Bit Name
FSO
PWM_FO
FS1
PWM_F1
FS2
RSVD
FS3
HPF_FO
FS4
HPF_F1
Default
Value
0
0
0
0
1
SNVS312D – JANUARY 2005 – REVISED MAY 2013
Table 4. Frequency Select Register
Condition
Function
0
Programs the oscillation frequency of the PWM. PWM oscillation frequency is
set as follows:
1
PWM_F<1:0>
PWM Frequency
00
0
01
15kHz
60Hz
10
7Hz
1
11
4Hz
0
RESERVED
1
0
Programs the internal high pass filter cutoff frequency. High pass filter cutoff
1
frequency is set as follows:
0
HPF_F<1:0>
High Pass Filter Cutoff Frequency
00
3.5kHz
01
1
10
6.3kHz
6.3kHz
11
8.9kHz
Data Bit
PSO
PS1
PS2
PS3
PS4
Bit Name
I²C_SEL
I²C_LED1
I²C_LED2
I²C_LED3
RSVD
Table 5. Pattern Select Register
Default Value
0
0
0
0
0
Condition
0
1
0
1
0
1
0
1
0
1
Function
Enables LED drivers to be controlled by audio
synchronization
Enables LED drivers to be controlled through I²C
Disables the LED1 driver, if I²C_SEL is set
Enables the LED1 driver, if I²C_SEL is set
Disables the LED2 driver, if I²C_SEL is set
Enables the LED2 driver, if I²C_SEL is set
Disables the LED3 driver, if I²C_SEL is set
Enables the LED3 driver, if I²C_SEL is set
RESERVED
RESERVED
Data Bit
Bit Name
CSO
ILED1_0
CS1
ILED1_1
CS2
ILED2_0
CS3
ILED2_1
Default
Value
0
1
0
1
Table 6. Current Select Register
Condition
0
1
0
1
0
1
0
1
Function
Programs the current drive of the LED1 driver. Current drive for LED1 is set
as follows:
ILED1<1:0>
Current Drive Setting
00
0.66X
01
1X
10
1.33X
11
2X
Programs the current drive of the LED2 driver. Current drive for LED2 is set
as follows:
ILED2<1:0>
Current Drive Setting
00
0.66X
01
1X
10
1.33X
11
2X
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