NXP Semiconductors PCA9955, Руководство пользователя, Страница: 9 / 16

UM10572 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2012. All rights reserved.
User manual Rev. 1 — 7 June 2012 9 of 16
NXP Semiconductors
UM10572
PCA9955 demonstration board OM13330
– ‘Other’ GRPPWM is group PWM for global brightness control, GRPFREQ is group
frequency for global blinking control when group control = blinking in Mode 2
register, PWMALL is brightness control for all LED outputs, OFFSET is control LED
output delay offset, IREFALL is control output current for all LEDs as shown in
Figure 10 .
4. Click the ‘LEDOUT’ configuration screen and select ‘PWMn & GRPPWM’ for LED[1:3]
(see Figure 8 ).
5. Click the ‘Output Gain’ configuration screen and adjust the IREF[1:3] = 0x30 for
LED[1:3] output current at 3.8 mA = 48
×
80
μ
A (see Figure 9 ).
6. Click the ‘PWM 0 to 7’ configuration screen and move the PWM1 (red) PWM2 (green)
PMW3 (blue) bars for color mixing (see Figure 6 ).
7. Once you set a color on D3 RGB LED with the PWM[1:3] values, click the ‘Other’
configuration screen and move the GRPPWM bar for dimming effect (see Figure 10 ).
Fig 5. Drop-down menu selections