Control Registers - NS LP3931 Manual

Recommended External Components
Symbol
C V Bypass Capacitor
VDD1 DD1
C V Bypass Capacitor
VDD2 DD2
C Output Capacitor from FB to GND
OUT
C Input Capacitor from Battery Voltage to GND
IN
C V Bypass Capacitor
VDDIO DD_IO
RT Oscillator Frequency Bias Resistor
RSO SO Output Pull-up Resistor
C Reference Voltage Capacitor, between V
VREF
L Boost Converter Inductor
BOOST
D Rectifying Diode, V
OUT
RGB1 RGB LED1
RGB2 RGB LED2
R , R , R Current Limit Resistor
R1 G1 B1
R , R , R Current Limit Resistor
R2 G2 B2
LEDs White LEDs
Note 15: Resistor RT accuracy specification change from 1% → 5% will be seen on timing accuracy of RGB block. Also the boost converter's switching frequency
will be affected.

Control Registers

Control registers and register bits are shown in the following table.
ADDR REGISTER
00H RGB Control register1
01H red1_on_off
02H green1_on_off
03H blue1_on_off
04H r1slope, r1duty
05H g1slope, g1duty
06H b1slope, b1duty
07H RGB Control register2
0BH enables
0DH boost output
2AH red2_on_off
2BH green2_on_off
2CH blue2_on_off
2DH r2slope, r2duty
2EH g2slope, g2duty
2FH b2slope, b2duty
Default value of each register is 0000 0000 except boost output which is 0011 1111 (5V).
List of External Components
Symbol Explanation
REF
@ Maxload
F
D7 D6
rgb pwm rgb start
r1_on[3] r1_on[2]
g1_on[3] g1_on[2]
b1_on[3] b1_on[2]
r1slope[3] r1slope[2]
g1slope[3] g1slope[2]
b1slope[3] b1slope[2]
cycle[1] cycle[0]
nstby
boost[7] boost[6]
r2_on[3] r2_on[2]
g2_on[3] g2_on[2]
b2_on[3] b2_on[2]
r2slope[3] r2slope[2]
g2slope[3] g2slope[2]
b2slope[3] b2slope[2]
(Continued)
Value Unit
100 nF
100 nF
10 µF
10 µF
100 nF
82 kΩ
100 kΩ
and GND 100 nF
10 µH
0.3
(See Application Note AN-1291 for resistor size calculation)
D5 D4
rsw1 gsw1
r1_on[1] r1_on[0] r1_off[3]
g1_on[1] g1_on[0] g1_off[3]
b1_on[1] b1_on[0] b1_off[3]
r1slope[1] r1slope[0] r1duty[3]
g1slope[1] g1slope[0] g1duty[3] g1duty[2] g1duty[1]
b1slope[1] b1slope[0] b1duty[3] b1duty[2] b1duty[1]
r1_pwm g1_pwm b1_pwm
en_boost en_flash1 en_flash2
boost[5] boost[4] boost[3]
r2_on[1] r2_on[0] r2_off[3]
g2_on[1] g2_on[0] g2_off[3] g2_off[2]
b2_on[1] b2_on[0] b2_off[3]
r2slope[1] r2slope[0] r2duty[3]
g2slope[1] g2slope[0] g2duty[3] g2duty[2] g2duty[1]
b2slope[1] b2slope[0] b2duty[3] b2duty[2] b2duty[1]
15
Recommended Type
Ceramic, X7R
Ceramic, X7R
Ceramic, X7R/Y5V
Ceramic, X7R/Y5V
Ceramic, X7R
1% (Note 15)
Ceramic, X7R
Shielded, Low ESR, I
V Schottky Diode
User Defined
D3 D2 D1
bsw1 rsw2 gsw2
r1_off[2] r1_off[1]
g1_off[2] g1_off[1]
b1_off[2] b1_off[1]
r1duty[2] r1duty[1]
r2_pwm g2_pwm
boost[2] boost[1]
r2_off[2] r2_off[1]
g2_off[1]
b2_off[2] b2_off[1]
r2duty[2] r2duty[1]
∼1A
SAT
D0
bsw2
r1_off[0]
g1_off[0]
b1_off[0]
r1duty[0]
g1duty[0]
b1duty[0]
b2_pwm
boost[0]
r2_off[0]
g2_off[0]
b2_off[0]
r2duty[0]
g2duty[0]
b2duty[0]
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