ncp5890 ON Semiconductor, ncp5890 Datasheet
ncp5890
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ncp5890 Summary of contents
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... NCP5890 Light Management IC Dedicated for LCD Backlighting and Multi-LED Fun Light Applications The NCP5890 is part of the Light Management IC (LMIC) family fully programmable subsystem that manages multiple illumination functions integrated into the silicon. Features • Output Voltage Capability • Include Three Independent PWM to Control LED Segments • ...
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GND Under Voltage Detection IPK R1 I−PEAK 22k 6 GND 1 SCL SDA 2 I2CADR 3 GND 1Hz IREF R2 12k 7 GND VSB U3 SFH5711 4 Log R4 AMBS 4 220k 5 R3 22k 2.2 ...
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... Photo Sense PHTIM 3 bits DIGITAL COMPARATOR Low I−LED 5 bits DIGITAL COMPARATOR High I−LED 5 bits DIGITAL ANALOG COUNTER & PROCESSING MONITORING 1.3MHz oscillator 1 kHz oscillator Figure 3. Basic NCP5890 Structure http://onsemi.com 3 PWM0 Drive PWM1 Drive PWM2 Drive 5 bits I−LED GND I−LED CONTROL 1 ...
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... DIGITAL gram the mode of operation and to set up the output current. 3 I2CADR INPUT, This pin is used to select the I2C address of the NCP5890: DIGITAL In order to avoid any risk during the operation, the digital levels are intended to be hardwired prior to power up the system. 4 VSB POWER, This pin provides a switched voltage, derived from the Vbat supply, to bias the external photo sense ...
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MAXIMUM RATINGS (Note 2) Symbol V Power Supply BAT V Output Switching Voltage LX SCL, SDA Digital Input Voltage Digital Input Current ESD Human Body Model 1500 100 pF (Note 3) Machine Model P UQFN16 ...
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ANALOG SECTION: (Typical values are referenced to T temperature, unless otherwise noted), operating conditions 2.85 V < Vbat < 5.5 V, unless otherwise noted. Pin Symbol 7 I Reference Current @ Vref = 1144 mV (Note 8) REF 6 I ...
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... Vbat Figure 4. Simplified Boost Structure Manufacturers Figure 5. Typical Switching Operation The physical address of the NCP5890 can be selected as 0111 001X or 0111 010X (the X being the Read / Write identifier as defined by the I2C specification) depending upon the digital status present at the I2CADR pin: http://onsemi.com ...
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... DATA update. The low nibble contains the selected register number as depicted in Table 2. The high nibble is reserved for future use. The last code $0F is reserved for ON Semiconductor to control the manufacturing test and access to this register is not permitted outside the ON Semiconductor final test facilities. B2 ...
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Table 3. Registers Identification DEC Register functions 1 Shut Down the chip 2 Select I−LED current setup and immediate LED update 3 Select I−LED target Gradual Dimming command UP 4 Select I−LED target Gradual Dimming command DOWN 5 Set Timing ...
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The ILED current is given by Table percentage of the maximum programmed ILED value (100% will give 25 mA when Iref = 100 mA). Table 4. Output Current Programmed Value (Iout % = F(Step)) $Step Iout % ...
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... The gradual dimming sequence must be set up before a new output current data byte is sent to the NCP5890. At this point, the brightness sequence takes place when the new data byte is acknowledged by the internal I2C decoder. ...
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Figure 10. Typical Gradual Dimming UPWARD Keyboard Dimming The keyboard shares the same I−LED peak current with the backlight, but the built−in PWM structure makes possible a dynamic independent control of three sets of LED. Each PWM is associated with ...
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Ambient Light Control The ambient light can be monitored extra photo diode, to automatically adjust the I−LED peak current as a function of the ambient light. A dedicated I2C command is used to activate or de−activate this function. ...
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When the photo sense returns a lower ambient light level in comparison to the maximum level set up by the user, the I−LED decreases with a timing defined by an I2C PHCLK[0.. RESET 0 0 Bits ...
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ILED Max (25 mA, programmable) Ambient Light ILED Min (Programmable) Photo Sense The photo sense register is loaded with the I2C content Ambient Light < I2C ILED : the Photo sense controls the ILED The Photo Sense cannot force t ...
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... Strategy #3: the three PWM share the same rise and fall time but they can be activated independently. Startegy#4: the three PWM operate randomly: the NCP5890 is capable of operating under such conditions, but care must be observed since such random PWM (as depicted by the circles) might be a stress from a human eye stand point ...
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... GND I−Load Max = 25mA D1 D2 Vout 16 PWM1 DZ1 9.5V PWM2 DZ2 9.5V GND PWM3 DZ3 9.5V GND GND +Vbat MBR0540 L1 4.7 mF D11 U1 NCP5890 Vbat 1 SCL 16 2 Vos SDA 3 I2CADR 4 VSB 12 R3 PWM1 22 k GND 11 5 PWM2 AMBS 2 PWM3 IREF 12 k ...
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... UNDERVOLTAGE LOCKOUT The VUVLO circuit is used to disconnect the chip when the input voltage is below the minimum operating value. Vbat V UVLO Engage the shut down mode Figure 21. Undervoltage Lockout Basic Mechanism +Vbat NSR0130M2T5G L1 4 D11 U1 NCP5890 Vbat 1 SCL 2 16 Vos SDA 3 I2CADR 4 ...
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... PAD AS WELL AS THE TERMINALS. MILLIMETERS DIM MIN MAX A 0.45 0.60 A1 0.00 0.05 A3 0.127 REF b 0.20 0.30 D 3.00 BSC D2 1.60 1.80 E 3.00 BSC E2 1.60 1.80 e 0.50 BSC K 0.20 −−− L 0.30 0.50 SOLDERING FOOTPRINT* 0.50 PITCH 2X 2X 1.55 3.30 1 16X 0.29 DIMENSIONS: MILLIMETERS ON Semiconductor Website: www.onsemi.com Order Literature: http://www.onsemi.com/orderlit For additional information, please contact your loca Sales Representative NCP5890/D ...