lx1977 Microsemi Corporation, lx1977 Datasheet
lx1977
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lx1977 Summary of contents
Page 1
... The LX1977 is available in an 8-pin MSOP package, and is operational over the ambient temperature range -40˚C to 85˚C. THERMAL RESISTANCE Junction Temperature Calculation: T The θ numbers are guidelines for the thermal performance of the JA device/pc-board system ...
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... Ground Reference For Power And Signal Output SS 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 ® LX1977 D 4000 V DD 3000 µP 2000 1000 ...
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... 2000 lux 500 lux 1000 lux 2000 lux lux 25°C, RANGE_SEL=00b =100mS INT Microsemi Analog Mixed Signal Group LX1977 P D RODUCTION ATASHEET ≤ ≤ T 70°C and the A Min Typ Max 3.0 4.5 0.2 15 38.91 40.96 43.00 36.86 40.96 45.06 555 ...
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... SDA Part LX1977 SCL R SET ADR INT V SS 810nm Figure 3 – ALS Output Measurement Microsemi Analog Mixed Signal Group LX1977 P D RODUCTION ATASHEET ≤ ≤ T 70°C and the A Min Typ Max 18 10 400 0.8 2 ...
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... Only standard two-wire 2 SMBus and I C compatible serial bus and protocols may be used for this device. The LX1977 can be configured for one of the three addresses by connecting the ADR input pin to ground simply leaving it OPEN. ...
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... A NACK will signify the end of the Read command. Once the LX1977 has placed the byte(s) of data on the serial bus, it will ignore all additional bus activity until the next “Start Condition” is detected. ...
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... Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 SMBus Ambient Light Sensor ® 2 Table 5: SMBus (I C compatible) Timing Parameter SU:DAT HIGH t SU:STA t HD:DAT S Figure 4 – SMBus Timing Measurement Microsemi Analog Mixed Signal Group LX1977 P D RODUCTION ATASHEET FAST_MODE Units MIN MAX 10 400 kHz 1.3 - µs 0.6 - µs 0.6 - µs ...
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... The individual protocol format is shown in tables below. For a complete description of SMBus protocols, please review the SMBus Specification at www.smbus.org/specs. S Start Condition S Write (bit value Stop Condition P Master-to-Slave Grey shading represents cycles during which the LX1977 “owns” or “drives” the Data line. All other cycles are driven by the host Slave Address ...
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... SMBus pull-up resistors should be provided on the system, and is not provided by the LX1977 device. • The ALS shall NACK any SMBus operation directed to it that addresses a register that is not defined in this specification. ...
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... ADC_MOD (bit W this bit sets ADC to one time conversion mode and 1 sets ADC to continuous mode when Note: These two bits should be controlled together. When these two bits are set to 11, LX1977 will be in continuous mode. When a restart of the continuous mode is need, 01 should be written to these bits and then 11 should be written afterwards ...
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... COUNT 100 ms COUNT INT COUNT INT Microsemi Analog Mixed Signal Group LX1977 P D RODUCTION ATASHEET Time INT 4095 Counts 2047 Page 11 ...
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... A 0 Register 00h could be read back by the host via Receive Byte protocol or Read Byte protocol. When LX1977 receives a Receive Byte protocol, it will send a copy of register 00 data back to the host. When it receives Read Byte protocol, it will put register 00 data in the Data Byte field and send the data back to host. See Table 11 & Table 19 for details. ...
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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 Conversion Mode and start ADC 3) Bit 3 will select 40.96 kHz clock frequency as the Sigma-Delta ADC clock ...
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... Light input Lux and D COUNT LX1977 output D determined by integration time as shown above. In the Electrical Characteristics table, D accordance with the specified light input at ADC Clock = 40.96 kHz, integration time = 100ms and 500 lux 1000 lux 5000 lux and 0 ~ 2500 lux range. D measurement range selected ...
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... A 0 Register 01h could be read back by the host by using a Read Byte protocol. When LX1977 receives a Read Byte protocol, it will put register 01h data into the Data Byte field and send the data back to the host. Please see Table 11 & Table 19 for details. ...
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... Bit 2, 1 & 0 will set LX1977 to generate interrupt after D or below the low threshold for 5 consecutive times Register 01h could be read back by the host by using Read Byte protocol. When LX1977 receives Read Byte protocol, it will put register 01 data in the Data Byte field and send back to host. See Table 11 for details. ...
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... Data bit 4 Data bit 3 Higher Byte Register 07h COUNT Data bit 11 is greater than 6.25ms (in 40.96kHz Mode INT Microsemi Analog Mixed Signal Group LX1977 P D RODUCTION ATASHEET is higher than this COUNT value is higher COUNT value is lower COUNT ...
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... 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 ® Table 34: Identification Register 08h MFG2 MFG1 MFG0 Microsemi Analog Mixed Signal Group LX1977 P D RODUCTION ATASHEET REV2 REV1 REV0 Page 18 ...
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... INT LX1977 D 4000 3000 0 ~ 500 lux 2000 0 ~ 1000 lux 0 ~ 5000 lux 0 ~ 2500 lux 1000 0 4000 5000 6000 0 1000 Chart 2 – LX1977 D 4000 TINT=6.25mS TINT=25mS 3000 TINT=50mS TINT=100mS 2000 1000 0 0 500 300 350 400 450 500 @ Different T Microsemi ...
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... Chart 10 – Angular Response Y Direction Microsemi Analog Mixed Signal Group LX1977 P D RODUCTION ATASHEET LX1977 Temperature Performance (100mS, 0~500 Lux Range, 200 Lux Input, Vcc=3.3V) -40 - TEMP (C) Chart 6 – Temperature COUNT ...
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... SMBus Ambient Light Sensor ® Figure 5 – Typical Application 1 2.5V 0.1µF BRT CCLF or LED BACKLIGHT CONTROLLER Figure 6 – Typical Application 2 Microsemi Analog Mixed Signal Group LX1977 D RODUCTION ATASHEET LX1800 To µP V SCL DD REF SCD Part AIN GND ...
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... A and B are the dimensions of the glass top window. 4. Values listed in the table are typical numbers. Microsemi Analog Mixed Signal Group LX1977 M I ILLIMETERS NCHES MAX MIN MAX – 1.10 – 0.043 0.15 0.002 0.006 0.41 0.010 0.016 0.23 0.005 0.009 3.10 0.114 0.122 ...
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... REF 3.3mm ±0.1 8mm ±0.1 Ref 0.4mm DU Package Tape and Reel Information Microsemi Analog Mixed Signal Group LX1977 4mm ±0.1 Pin 1 12mm ±0.3 3.3mm ±0.1 Ø 1.6mm ±0 Page 23 ...