LX1977IDU MICROSEMI [Microsemi Corporation], LX1977IDU Datasheet
LX1977IDU
Related parts for LX1977IDU
LX1977IDU Summary of contents
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... A RoHS Compliant / Pb-free - LX1977IDU Note: Available in Tape & Reel. Append the letters “TR” to the part number. (i.e. LX1977IDU -TR ............................................................................................................... -0 Input Voltage to All Input Pins ........................................................... -0. SMBus Pin Voltage (SCL, SDA) .................................................................. -0.3V to 5.5V SMBus Pin Current (SCL, SDA) ........................................................................... < ...
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SDA R SET Part SCL LX1977 INT ADR R V SET ...
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TM Unless otherwise specified, the following specifications apply over the operating ambient temperature 0°C following test conditions: 3.0V ≤V ≤ 4.5V DD Parameter Symbol P S OWER UPPLY Operational Voltage V DD Supply Current I DD Supply Current I DD ...
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TM Unless otherwise specified, the following specifications apply over the operating ambient temperature 0°C following test conditions: 3.0V ≤V ≤ 4.5V DD Parameter Symbol SMB I US NTERFACE Clock Frequency F CLK High Level Input Voltage V SDA V Low ...
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ASIC UNCTIONALITY The LX1977 is an ALS with an I interface. It contains a high sensitivity close to human eye response photodiode, a 12-bit Sigma-Delta ADC and a SMBus interface. The Sigma-Delta ADC converts photodiode current to ...
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TM W/R bit is a “0”, signifying a “Write” command, the next byte of data sent from the host will be a Data Byte or a Command Code (also called index), depending on whether there is a Stop Condition afterwards. ...
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TM SMB OMMON PECIFICATIONS The diagram below illustrates the various SMBus timings and sets the context for the specifications to follow. Note that the following are not production tested specifications, but are common SMBus protocol specifications ...
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TM SMB OMMUNICATION ROTOCOL LX1977 employs the following SMBus 2.0 protocols that are also compatible to I communicate with LX1977 must be per standard SMBus specification version 2.0 or higher. • Send Byte • Receive Byte • ...
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Slave Address Slave Address Wr A Command Code 0 SMB R US EQUIREMENTS • When the ALS SMBus interface is not powered, it will not affect other SMBus ...
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TM Command Register 00h ( ADC_FLAG ALS_ENA START_ADC ADC_MOD Read Only Read / Write Index Address = 00000000b or 00h Access = Read / Write Default = 00000000b This register contains bits for configuring and controlling ...
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ADC_CLK (bit W): Selects the internal ADC clock speed when CLK_SEL (bit 7) of register 01h select clock speed to normal (40.96 kHz select clock speed to ¼ ...
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TM RANGE_SEL = 01b (0 ~ 1000 lux) RANGE_SEL = 10b (0 ~ 5000 lux) RANGE_SEL = 11b (0 ~ 2500 lux) Note: ADC output count will be always in the range as specified in the above table. For example, ...
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TM This protocol will send commands to LX1977 and will write the command byte into register 00h for configuring the device settings. 1) Bit 6 will enable LX1977 ALS function 2) Bit 5, 4 will set ADC mode to Continuous ...
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2500 1 1 When range is selected, the D table for the values 500 lux 1000 lux 5000 and 0 ~ 2500 lux light input. The equations for calculating between ...
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TM Note: (1) When INT_FLAG of register 00h is cleared via SMBus command after an interrupt (2) For out-of-range conditions in the same direction, the persistence counter increments. If (3) Note that once the interrupt is triggered and the INT ...
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TM 1) Bit 7 will select the internal clock 2) Bit 6 & 5 will set detectable range 500 lux 3) Bit 4, 3 will set the integration time or conversion time to either 50ms or 200ms ...
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TM Index Address = 00000100b, 00000101b or 04h, 05h Access = Read / Write Default = 11111111b, 00001111b These two registers set the high threshold value of the interrupt function. If the ALS readout D value for the period of ...
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TM Identification Register 08h ( MFG4 MFG3 0 0 Index Address = 00001000b or 08h Access = Read Only Default = 00001100b Copyright © 2010 Rev. 1.0, 2010-03-25 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 ...
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LX1977 D vs LUX @ Fosc=40.96kHz, T COUNT Vcc = 3.3V 250 225 200 175 150 125 100 ...
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Spectral Response 1.0 0.8 0.6 0.4 0.2 0.0 300 350 400 450 500 550 Wavelength (nm) Chart 5 – ...
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SDA SET Part SCL LX1977 267k, INT ADR R V SET SS %1 Copyright © 2010 Rev. 1.0, 2010-03-25 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 SMBus Ambient Light Sensor ® ...
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TM DU Copyright © 2010 Rev. 1.0, 2010-03-25 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 (SMBus) Ambient Light Sensor ® ...
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Ø 1.55mm ±0.05 0.3mm ±0.05 5.5mm ±0.1 1.0mm ±0.1 1.3mm ...