ams Datasheet

Page 9

[v1-01] 2018-Apr-23

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TSL2561 − Electrical Characteristics

Note(s):

1. Optical measurements are made using small-angle incident radiation from light-emitting diode optical sources. Visible 640nm LEDs

and infrared 940nm LEDs are used for final product testing for compatibility with high-volume production.

2. The 640nm irradiance Ee is supplied by an AlInGaP light-emitting diode with the following characteristics: peak wavelength

λp = 640nm and spectral halfwidth Δλ½ = 17nm.

3. The 940nm irradiance Ee is supplied by a GaAs light-emitting diode with the following characteristics: peak wavelength λp =940nm

and spectral halfwidth Δλ½ = 40nm.

4. Integration time Tint, is dependent on internal oscillator frequency (fosc) and on the integration field value in the timing register as

described in the Register Set section. For nominal fosc = 735kHz, nominal Tint = (number of clock cycles)/fosc.

Field value 00: Tint = (11 × 918)/fosc = 13.7ms

Field value 01: Tint = (81 × 918)/fosc = 101ms

Field value 10: Tint = (322 × 918)/fosc = 402ms

Scaling between integration times vary proportionally as follows: 11/322 = 0.034 (field value 00), 81/322 = 0.252 (field value 01),

and 322/322 = 1 (field value 10).

5. Full scale ADC count value is limited by the fact that there is a maximum of one count per two oscillator frequency periods and also

by a 2-count offset.

Full scale ADC count value = ((number of clock cycles)/2 − 2)

Field value 00: Full scale ADC count value = ((11 × 918)/2 − 2) = 5047

Field value 01: Full scale ADC count value = ((81 × 918)/2 − 2) = 37177

Field value 10: Full scale ADC count value = 65535, which is limited by 16-bit register. This full scale ADC count value is reached for

131074 clock cycles, which occurs for Tint = 178ms for nominal fosc = 735kHz.

Rv

Illuminance

responsivity

Fluorescent light

source:

Tint = 402ms

Ch0

36

counts/lux

Ch1

4

Incandescent light

source:

Tint = 402ms

Ch0

144

Ch1

72

ADC count

value ratio:

Ch1/Ch0

Fluorescent light

source:

Tint = 402ms

0.11

Incandescent light

source:

Tint = 402ms

0.5

RV

Illuminance

responsivity,

low gain

mode (6)

Fluorescent light

source:

Tint = 402ms

Ch0

2.3

counts/lux

Ch1

0.25

Incandescent light

source:

Tint = 402ms

Ch0

9

Ch1

4.5

(Sensor

Lux)/(actual

Lux), high gain

mode (7)

Fluorescent light

source:

Tint = 402ms

0.65

1

1.35

Incandescent light

source:

Tint = 402ms

0.60

1

1.40

Symbol

Parameter

Test

Conditions

Channel

TSL2561T

Unit

Min

Typ

Max