MAX44000 Maxim, MAX44000 Datasheet
MAX44000
Related parts for MAX44000
MAX44000 Summary of contents
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... Rev 0; 10/11 Ambient and Infrared Proximity Sensor General Description The MAX44000 combines a wide-dynamic range ambient light sensor with an integrated infrared proximity sensor. The perfect solution for touch-screen portable devices. The IC can consume as low as 11µA (time averaged) in ambient light sensing plus proximity sensing, including external IR LED current ...
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... Continuous Input Current into Any Terminal ................... Q20mA Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability ...
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... T DD MIN MAX PARAMETER SYMBOL IR LED TRANSMITTER Minimum IR LED Drive Current Sink Maximum IR LED Drive Current Sink Current Control Step Current Control Accuracy DRV Leakage Current Voltage Compliance of DRV Pin Internal Transmit Pulse Width POWER SUPPLY Power-Supply Voltage ...
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Ambient and Infrared Proximity Sensor ELECTRICAL CHARACTERISTICS (continued 1.8V, T – -40°C to +105° MIN MAX PARAMETER SYMBOL TIMING CHARACTERISTICS Serial-Clock Frequency Bus Free Time Between STOP and START Hold ...
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Ambient and Infrared Proximity Sensor (V = 1.8V, T – -40 ° +85 ° C, unless otherwise noted. All devices are 100% production tested MIN MAX Temperature limits are guaranteed by design.) LIGHT ...
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... DRV 40 20 10mA I SETTING DRV 20 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 V (V) DRV A SUPPLY CURRENT vs. TIME MAX44000 toc08 AMBIENT + PROXIMITY MODE I DRV 50mA/div I DD 200µA/div 100µs/div TOTAL CURRENT CONSUMPTION INCLUDING IR LED CURRENT vs. IR LED CURRENT LEVEL TOTAL DD IR_LED 60 AMBIENT + PROXIMITY MODE ...
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... EP — Exposed Pad internally connected to GND. EP must be connected to GND. Detailed Description The MAX44000 combines a wide-dynamic range ambi- ent light sensor with an integrated infrared proximity sensor. The die is placed inside an optically transparent (UTDFN-Opto) package. A photodiode array inside the IC converts the light to a current, which is then pro- cessed by low-power circuitry into a digital value ...
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... Figure 2. Green Channel and IR Channel Response at Identical Gains on a Typical MAX44000 120 100 GREEN CHANNEL 80 RED CHANNEL CIE CURVE ...
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Ambient and Infrared Proximity Sensor Proximity Light Sensing The proximity sensing uses an external, pulsed infrared LED source to emit controlled amounts of infrared radia- tion. When an external object reflects back some of this infrared radiation back to the ...
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Ambient and Infrared Proximity Sensor REGISTER B7 B6 Threshold Persist Timer PROX Threshold ABOVE Indicator PROX Threshold Digital Gain Trim of Green Channel Digital Gain Trim of Infrared Channel The individual register bits are explained below. Default power-up bit states ...
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Ambient and Infrared Proximity Sensor BIT interrupt trigger event has occurred. The IR proximity receive intensity has exceeded the threshold limit for greater than persist 1 timer count PRXPST[1:0]. This bit also causes the INT pin to ...
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Ambient and Infrared Proximity Sensor BIT 1 0 The PRXINTS bit remains unasserted, and proximity channel readings are not compared with interrupt thresholds. Detection of a proximity interrupt event triggers a hardware interrupt (INT pin is pulled low) and sets ...
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Ambient and Infrared Proximity Sensor The 2-bit ALSTIM[1:0] sets the integration time for ALS ADC conversion, as shown in Table 1. Table 1. Ambient ADC Conversion Time ALSTIM[1:0] INTEGRATION TIME (ms) 00 100 6.25 11 1.5625 The ...
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Ambient and Infrared Proximity Sensor REGISTER B7 B6 ADC High Byte (ALS) OFL ADC Low Byte (ALS) The 2 bytes here (ALSDATA[13:0]) hold the results of the ALS signal conversion. The resolution and bit length of the result is controlled ...
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... B6 Threshold Persist Timer The MAX44000 incorporates a persist function that allows the users to set the number of consecutive triggers before interrupt. PRXPST[1:0] and ALSPST[1:0] set one of four persist values that control how readily the interrupt logic reacts to a detected event. This feature is added to reduce false or nuisance interrupts. ...
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Ambient and Infrared Proximity Sensor REGISTER B7 PROX Threshold Indicator PROX Threshold The value set by PRXTHR[7:0] in combination with the ABOVE bit controls the operation of the proximity interrupt func- tion. If the ABOVE bit is set to 1, ...
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... Further, the proximity sensor uses a single-pulse scheme for the IR transmitter that eliminates red-glow problems seen in competing solutions to drive 850nm IR LEDs, while also reducing average IR LED power consumption to less than 0.1% of the IR LED peak current. ______________________________________________________________________________________ 2mm MAX44000 TOP VIEW 1.226mm 0.753mm GND 2 PHOTO- 0.39mm DIODE DRV 3 ...
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... Ambient and Infrared Proximity Sensor Interrupt Pin Voltage Compliance The interrupt pin can withstand external voltages when in high-impedance mode per the absolute maximum ratings of the IC. However, when the voltage on the INT pin is higher than the V DD when external pullup voltage is greater than V there is a small leakage current of 25µ ...
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Ambient and Infrared Proximity Sensor SDA t SU,DAT t LOW SCL t HIGH t HD,STA t R START CONDITION Figure 4. 2-Wire Interface Timing Diagram One data bit is transferred during each SCL cycle. The data on SDA must remain ...
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... STOP condition. Figure 8 illustrates the frame format for reading 1 byte from the IC. Figure 9 illustrates the frame format for reading two registers consecutively without a STOP condition in between reads. ACKNOWLEDGE FROM MAX44000 0 A REGISTER ADDRESS ACKNOWLEDGE FROM MAX44000 ...
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... A R/W Figure 9. Reading Two Registers Consecutively Without a STOP Condition Between Reads ______________________________________________________________________________________ ACKNOWLEDGE FROM MAX44000 REGISTER ADDRESS A Sr SLAVE ADDRESS REPEATED START ACKNOWLEDGE FROM MAX44000 REGISTER ADDRESS SLAVE ADDRESS REPEATED START ACKNOWLEDGE FROM MAX44000 ACKNOWLEDGE FROM MAX44000 REGISTER ADDRESS ...
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... Ambient and Infrared Proximity Sensor V = LED 1.7V TO 3.6V 1.7V TO 3.6V 1µ LED GND MAX44000 DRV 22 _____________________________________________________________________________________ 1.7V TO 3.6V 10kI 10kI 10kI SDA SCL INT SDA SCL SLAVE_1 SLAVE_1 Typical Applications Circuit SDA SCL INT µC SDA ( MASTER) SCL ...
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... Ambient and Infrared Proximity Sensor For the latest package outline information and land patterns (footprints www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status ...
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... Initial release Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ...