XRP6840 Exar Corporation, XRP6840 Datasheet
XRP6840
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XRP6840 Summary of contents
Page 1
... A standard 2-line I C serial interface allows the dynamic programming of LED currents in torch and flash modes, flash timeout, channel enable, gain control, capacitor charge voltage, and enable. The XRP6840 comes and 3 channel version supporting 440mA/2.15A per channel and 300mA/1.45A in torch/flash modes ...
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... All LEDs are Off J(max ESET_N STATUS1 Register [B7 B6] =00 Measure LED1 – LED3 XRP6840A, Table 6, averaged from all channels XRP6840B, Table 6, averaged from all channels XRP6840A, Table 5, averaged from all channels XRP6840B, Table 5, averaged from all channels XRP6840A, Note 2, averaged from all ...
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... Input Logic Low Voltage SDA, SCL, RESET_N, FLASH Input Logic High Voltage Turn-Off Time (T ) Into OFF Shutdown Flash Time Duration Before Standby SPECIFICATIONS DDRESSING ORMAT XRP6840 R/W Address S A 7-bit 1/0 Start Condition Acknowledgement sent by the slave © 2009 Exar Corporation ...
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... Default I C slave 7-bit address for XRP6840 is 0101000b IMING HARACTERISTICS V = 3.3V –40°C to 85° –40°C to 125°C. Unless otherwise noted Parameter Symbol Serial Clock Frequency Bus Free Time between a STOP and a START Hold Time, Repeated START ...
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... Exar Corporation Fig. 3: XRP6840 Block Diagram (XRP6840A Shown) XRP6840B – 2 Channel Version Fig. 4: XRP6840 Pin Assignment 5/ ...
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... Power ground pin. The Source of internal NMOS is connected to this pin. Active Low input pin. If RESET_N = 0, then XRP6840 is in Shut-down mode If RESET_N = 0 and STATUS1 register [B5 then reset all registers to logic low. If RESET_N = 0 and STATUS1 register [B5 then all bits of all registers will be saved ...
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... Information section of this datasheet. Fig. 5: High Efficiency Torch Mode I no supercap Fig. 7: High Efficiency Torch Mode, Input Current versus 200mA, no supercap LED 1100mA Fig. 9: In-rush Current with Li-ion Battery 0.6F Supercap, C =10µF CH1 = V IN © 2009 Exar Corporation ...
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... CH1 = FLASH, CH2 = RDY, CH3 =V F CH4 = I =2A/div LED Fig. 13: 200mA High Efficiency Torch Mode with 0.55F Supercap, CH1=V , CH2=V IN CH4=I =0.5A/div VIN Fig. 15: LED Current Settling Time: 0mA to 100mA. CH1=SDA, CH2=SCL, CH4=I © 2009 Exar Corporation ...
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... Fig. 17: LED Current Settling Time: 200mA to 0mA. CH1=SDA, CH2=SCL, CH4=I Fig. 19: LED Current Settling Time From Shutdown to 200mA. CH1=RESET_N, CH2=LEDx, CH4=I Fig. 21: Figure 21: Flash Mode Enable From Shutdown CH1=RESET_N, CH2=RDY, CH3=V © 2009 Exar Corporation ...
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... I ERIAL NTERFACE R EGISTERS The XRP6840 has five serially programmable data registers via the I²C interface. These registers can be reset to ‘0’ through power on reset or setting RESET_N, pin 6, to ‘0’. The first register is for Device Address as shown in Figure activated by ‘28’ HEX (7-bit format) ...
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... Addressing and Writing Data To write data to the XRP6840 one of the following two sequences is required: Easy shutdown/startup sequence XRP6840B [Slave Address with write bit][Data for Status] I /Ch. (mA) OUT 0 Full shutdown/startup sequence 597 [Slave Address with write bit][Data for Status] ...
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... Table 7: Auto Start Mode from STATUS1 Register When in Auto Gain Start Mode, the XRP6840 . For both Torch will charge up V available current within the constraints defined above for start-up. In this mode the XRP6840 will initialize the is LEDX system as follows: 1. Turn and V ...
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... V > When the input OUT IN current drops to approximately 400mA the XRP6840 is able to switch from 1x to 1.5x mode without exceeding 600mA. The switch from 1.5x mode to 2x mode occurs if V not reached V and when the input OUT_LIMIT current is below 300mA. After switching to 2x ...
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... The XRP6840 also has a built-in over current protection because when shorted, the XRP6840 will force the part mode and its output current is always limited to 600mA regardless of whether or not the part is in Auto or Programmed Start Modes. ...
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... To achieve 4.3A flash pulses, we recommend using 0.55F Super Capacitor EDLC2720-501-2F-50 with voltage rating of TYPICAL APPLICATION SCHEMATICS Fig. 22: XRP6840A - 3 Channel - 4.3A Total LED Flash Current © 2009 Exar Corporation ...
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... PACKAGE SPECIFICATION 20-P TQFN IN © 2009 Exar Corporation 16/ ...
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... While the information in this publication has been carefully checked; no responsibility, however, is assumed for inaccuracies. EXAR Corporation does not recommend the use of any of its products in life support applications where the failure or malfunction of the product can reasonably be expected to cause failure of the life support system or to significantly affect its safety or effectiveness. Products are not authorized for use in such applications unless EXAR Corporation receives, in writing, assurances to its satisfaction that: (a) the risk of injury or damage has been minimized ...