AS7221 datasheet(16/36 Pages) AMSCO

16 / 36 page

Page 16

ams Datasheet

Document Feedback

[v1-01] 2016-Dec-08

AS7221 − Detailed Description

Refer to the Figure above. When pulled down for more than

100ms the SYNC/RESN pin will reset the AS7221 Smart Lighting

Manager. In this case the push-button “overrides” the output of

the opto-coupler. Therefore a resistor should be placed in series

with the opto-coupler.

AS7221 Outputs

The AS7221 outputs, used to control dimming and LED

warm/cool strings, can be configured as either three PWM

outputs, two PWMs and one analog output, or two PWMs. The

PWMs are 12 bit and factory set to 888 Hz. Refer to the Figure

below.

The three PWM outputs, PWM_1, PWM_2 and PWM_3 all switch

with the same frequency, but are not simultaneous for better

EMI performance.

The PWM_1 output can be set to either analog (0-VDDHV) or

digital (0-VDDHV) dimming. Analog dimming range is 10-100%.

Digital Dimming range is 1-100%. PWM2 and PWM3 are used

for cool white and warm white LED color controlling. Either

string can be warm or cool as the AS7221 automatically

configures string color type. Range is 0-100% for both PWM2

and PWM3.

To set the desired device operation MODE use the appropriate

RMODE resistor, also shown in the Figure below.

Figure 19:

Outputs

Note(s):

1. For VDDHV>10.5, output max is 10V, else output max tracks VDDHV.

Indicator LED

An LED, connected to pin LED_IND, is used to indicate

programming progress of the device. During programming of

the AS7221 via an external SD card the indicator LED starts.

When programming is finished the indicator LED is off.

The LED_IND pin is set for 1mA operation by the AS7221 factory

firmware, and is not under user control.

Refer to the separate ams document for a complete description

of AS7221 Firmware Update Methodology.

MODE

RMODE

Setting

Outputs

PWM_1/0_10V_O

PWM_2 and PWM_3

100 Ω

0-10V analog

Analog 0-VDDHV (1)

Digital PWMs (0-VDD)

470 Ω

0-10V digital

Digital PWM (0-VDDHV) (1)

Digital PWMs (0-VDD)

1000 Ω

Digital 2-CH color tuning

n.a.

Digital PWMs (0-VDD), w/Dimming

AS7221 датащи(PDF) 16 Page - ams AG

AS7221 датащи(HTML) 16 Page - ams AG

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36

датащи скачать

ссылки URL