TSL2581CS TAOS, TSL2581CS Datasheet - Page 23

• Manufacturer Part Number: TSL2581CS
• Description: Light to Digital Converters Light to Digital 30x Sensitivity
• Manufacturer: TAOS

Specifications of TSL2581CS

• Data Bus Width: 16 bit
• Peak Wavelength: 625 nm, 850 nm
• Maximum Operating Frequency: 795 KHz
• Operating Supply Voltage: 2.7 V to 3.6 V
• Operating Current: 175 uA
• Maximum Operating Temperature: + 70 C
• Minimum Operating Temperature: - 30 C
• Interface Type: I2C
• Maximum Fall Time: 300 ns
• Maximum Rise Time: 300 ns
• Mounting Style: SMD/SMT
• Resolution: 16 bit
• Package / Case: DFN-6
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

//−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−
// Integration time scaling factors
//−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−
#define CH_SCALE 16 // scale channel values by 2^16
#define NOM_INTEG_CYCLE 148 // Nominal 400 ms integration.
//−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−
// Gain scaling factors
//−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−
#define CH0GAIN128X 107 // 128X gain scalar for Ch0
#define CH1GAIN128X 115 // 128X gain scalar for Ch1
//−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−
// FN Package coefficients
//−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−
// For Ch1/Ch0=0.00 to 0.30:
//
//
// For Ch1/Ch0=0.30 to 0.38:
//
//
// For Ch1/Ch0=0.38 to 0.45:
//
//
// For Ch1/Ch0=0.45 to 0.54:
//
//
// For Ch1/Ch0>0.54:
//
//
//−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−
#define K1C 0x009a // 0.30 * 2^RATIO_SCALE
#define B1C 0x2148 // 0.13 * 2^LUX_SCALE
#define M1C 0x3d71 // 0.24 * 2^LUX_SCALE
#define K2C 0x00c3 // 0.38 * 2^RATIO_SCALE
#define B2C 0x2a37 // 0.1649 * 2^LUX_SCALE
#define M2C 0x5b30 // 0.3562 * 2^LUX_SCALE
#define K3C 0x00e6 // 0.45 * 2^RATIO_SCALE
#define B3C 0x18ef // 0.0974 * 2^LUX_SCALE
#define M3C 0x2db9 // 0.1786 * 2^LUX_SCALE
#define K4C 0x0114 // 0.54 * 2^RATIO_SCALE
#define B4C 0x0fdf // 0.062 * 2^LUX_SCALE
#define M4C 0x199a // 0.10 * 2^LUX_SCALE
#define K5C 0x0114 // 0.54 * 2^RATIO_SCALE
#define B5C 0x0000 // 0.00000 * 2^LUX_SCALE
#define M5C 0x0000 // 0.00000 * 2^LUX_SCALE
// lux equation approximation without floating point calculations
//////////////////////////////////////////////////////////////////////////////
// Routine: unsigned int CalculateLux(unsigned int ch0, unsigned int ch0, int iType)
//
// Description: Calculate the approximate illuminance (lux) given the raw
//
//
//
// Arguments: unsigned int iGain − gain, where 0:1X, 1:8X, 2:16X, 3:128X
//
//
//
//
//
// Return:
//
The LUMENOLOGY r Company
Lux=0.13*Ch0−0.24*Ch1
Lux=0.1649*Ch0−0.3562*Ch1
Lux=0.0974*Ch0−0.1786*Ch1
Lux=0.062*Ch0−0.10*Ch1
Lux/Ch0=0
unsigned int tIntCycles − INTEG_CYCLES defined in Timing Register
unsigned int ch0 − raw channel value from channel 0 of TSL2581
unsigned int ch1 − raw channel value from channel 1 of TSL2581
unsigned int iType − package type (1:CS)
unsigned int − the approximate illuminance (lux)
channel values of the TSL2581. The equation if implemented
as a piece−wise linear approximation.
r
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LIGHT-TO-DIGITAL CONVERTER
See Timing Register
r
TSL2580, TSL2581
Copyright E 2010, TAOS Inc.
TAOS098 − MARCH 2010
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