ADP8861 Analog Devices, ADP8861 Datasheet
ADP8861
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ADP8861 Summary of contents
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... LED indication General backlighting of small format displays GENERAL DESCRIPTION The ADP8861 provides a powerful charge pump driver with independent control seven LEDs. These seven LEDs can be independently driven (typical). The seventh LED can also be driven (typical). All LEDs are pro- ...
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... ADP8861 TABLE OF CONTENTS Features .............................................................................................. 1 Applications ....................................................................................... 1 Typical Operating Circuit ................................................................ 1 General Description ......................................................................... 1 Revision History ............................................................................... 2 Specifications ..................................................................................... Timing Diagram .................................................................... 4 Absolute Maximum Ratings ............................................................ 5 Maximum Temperature Ranges ................................................. 5 Thermal Resistance ...................................................................... 5 ESD Caution .................................................................................. 5 Pin Configurations and Function Descriptions ........................... 6 Typical Performance Characteristics ............................................. 7 Theory of Operation ...................................................................... 11 Power Stage.................................................................................. 12 Operating Modes ........................................................................ 13 Backlight Operating Levels ...
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... Rev Page −40°C to +85°C, unless A Min Typ 2.5 2.05 1. mA, gain = 2× 4.5 0 26.2 30 24.4 52.5 60 48.8 2.0 1.5 0.5 3.0 3.8 4.3 4.9 162 200 180 100 ADP8861 = 1 μF, OUT Max Unit 5 μs μA 1.0 μA 7.2 mA 1.32 MHz % 34 0.5 μA Ω Ω Ω 5.5 ...
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... ADP8861 Parameter FAULT PROTECTION Start-Up Charging Current Source Output Voltage Threshold Exit Soft Start Short-Circuit Protection Output Overvoltage Protection Activation Level OVP Recovery Hysteresis Thermal Shutdown Threshold Hysteresis Isolation from Input to Output During Fault Time to Validate a Fault INTERFACE Operating V Voltage ...
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... For the LFCSP package, the exposed pad must be soldered to GND. Table 3. Thermal Resistance Package Type WLCSP LFCSP 1 N/A stands for not applicable. ESD CAUTION Rev Page Therefore, in situations where the ADP8861 − (θ × J(MAX) JA D(MAX) , θ (junction to board), and θ ...
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... ADP8861 PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS TOP VIEW (Not to Scale SCL 5 nRST NOTES 1. CONNECT THE EXPOSED PADDLE TO GND1 AND/OR GND2. Figure 3. LFCSP Pin Configuration Table 4. Pin Function Descriptions Pin No. LFCSP WLCSP Mnemonic 14 A3 VIN ...
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... V ( 0.4V D1: 2.0 2.5 3.0 3.5 4.0 4.5 V (V) IN Figure 9. Typical Diode Current vs –40°C I D1:D7 +25°C +85°C 5 +105° 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 V (V) HR ADP8861 = 1 μF, OUT 1.6 1.8 2 5.0 5 30mA 1.8 2 ...
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... ADP8861 3. 30mA D1: 0.2 0.4 0.6 0.8 1.0 1.2 V (V) HR Figure 11. Typical Diode Current vs. Current Sink Headroom Voltage ( 3. 0.40V D1:D7 0 –1 –2 –3 –4 –5 –6 –40 – JUNCTION TEMPERATURE (°C) Figure 12. Typical Change In Diode Current vs. Temperature 100mA OUT ...
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... OUT 80 110 450 400 1 350 300 250 2 200 150 100 OUT 0 5.0 5.5 Rev Page ADP8861 I = 140mA 3.85V OUT I = 210mA 4.25V OUT 3.0 3.5 4.0 4.5 5.0 V (V) IN Figure 20. Typical Efficiency (High Vf Diode (AC-COUPLED) 50mV/DIV IN V (AC-COUPLED) 50mV/DIV OUT I (AC-COUPLED) 10mA/DIV IN = 1µ 1µ ...
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... ADP8861 T V (AC-COUPLED) 50mV/DIV (AC-COUPLED) 50mV/DIV OUT 2 I (AC-COUPLED) 10mA/DIV 1µ 1µ 1µ 1µF IN OUT 120mA OUT Figure 23. Typical Operating Waveforms 2× 3. 500ns/DIV Rev Page (1V/DIV) OUT I (10mA/DIV (10mA/DIV) 100µ ...
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... THEORY OF OPERATION The ADP8861 provides a powerful charge pump driver with programmable LED control seven LEDs can be indepen- dently driven (typical) each. The seventh LED can also be driven (typical). All LEDs can be individually programmed or combined into a group to operate backlight ...
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... LEDs. Because a fixed charging and discharging combination must be used, only certain multiples of gain are available. The ADP8861 is capable of automatically optimizing the gain (G) from 1×, 1.5×, and 2×. These gains are accomplished with two capacitors (labeled C1 and C2 in Figure 25) and an internal switching network 1× ...
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... C commands are acknowledged (all registers are kept 2 C commands. nRST MUST BE HIGH FOR 20µs (MAX) 2 BEFORE SENDING I C COMMANDS nRST IS LOW, WHICH FORCES STANDBY LOW 2 AND RESETS ALL I C REGISTERS GAIN CHANGES OCCUR ONLY WHEN NECESSARY, BUT HAVE A MIN TIME BEFORE CHANGING SOFT START ADP8861 2 C receivers. ...
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... The law bits in Register 0x04 are used to change between these algorithms. By default, the ADP8861 uses a linear algorithm (law = 00), where the backlight current increases linearly for a correspond- ing increase in input code. Backlight current (in milliamperes) is determined by the following equation: Backlight Current (mA) = Code × ...
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... The backlight can be turned off at any point during the off timer countdown by clearing BL_EN. Rev Page DIM TIMER DIM TIMER RUNNING RUNNING BL_EN = 1 DIM_EN = 1 DIM_EN = 0 DIM_EN = 1 Figure 33. Dim Timer OFF TIMER RUNNING BL_EN = 1 BL_EN = 0 SET BY USER SET BY INTERNAL STATE MACHINE Figure 34. Off Timer ADP8861 BL_EN = 0 ...
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... ISCx_EN SET BY USER Figure 37. Independent Sink Blink Mode with Fading SHORT-CIRCUIT PROTECTION MODE The ADP8861 can protect against short circuits on the output (VOUT). Short-circuit protection (SCP) is activated at the point when VOUT < 55 during both startup and restart attempts (fault recovery). SCP sensing is reenabled 4 ms (typical) after activation ...
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... An interrupt flag is set at each OVP instance. THERMAL SHUTDOWN/OVERTEMPERATURE PROTECTION If the die temperature of the ADP8861 rises above a safe limit (150°C typical), the controllers enter thermal shutdown (TSD) protection mode. In this mode, most of the internal functions shut down, the part enters standby, and the TSD_INT interrupt (Register 0x02) is set. When the die temperature decreases below ~130° ...
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... ADP8861 1 VOUT < V – OVP V OVP(HYS) 0 VOUT > V OVP FAULT 1 1 VOUT < V – OVP V (HYS) OVP 0 VOUT > V OUT(REG) OVP FAULT 1 TRY TO REGULATE VOUT OUT(REG) VOUT > V OVP 1 VOUT < V – OVP V OVP (HYS) 0 VOUT > V OUT(REG) OVP FAULT ...
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... Never connect voltage supply, except through a ≥1 kΩ series resistor. (5) • The ADP8861 has an integrated noise filter on the nRST pin. resistance for the Under normal conditions not necessary to filter the reset DSON line. However, if the part is exposed to an unusually noisy signal beneficial to add a small RC filter or bypass capacitor on this pin ...
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... Figure 40. Generic Application Schematic ACCESSORY LIGHTS OR DISPLAY BACKLIGHT SUB-DISPLAY BL DL1 DL2 DL3 DL4 DL5 VIN C1 GND1 ADP8861 R3 R4 nRST SDA SCL nINT Figure 41. Application Schematic with Keypad Light Control Rev Page VOUT 1µF C1+ C1 1µF C1– C2+ C2 1µ ...
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... I C PROGRAMMING AND DIGITAL CONTROL 2 The ADP8861 provides full software programmability to facilitate its adoption in various product architectures. The default I address is 0101010x ( during write during read). There- fore, the default write address is 0x54 and the read address is 0x55. Note the following general behavior of registers: • ...
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... ADP8861 Table 7. Register Set Definitions Address (Hex) Register Name 0x00 MFDVID 0x01 MDCR 0x02 MDCR2 0x03 INTR_EN 0x04 CFGR 0x05 BLSEN 0x06 BLOFF 0x07 BLDIM 0x08 BLFR 0x09 BLMX 0x0A BLDM 0x0B to 0x0E Reserved 0x0F ISCFR 0x10 ISCC 0x11 ISCT1 0x12 ...
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... Device ID GDWN_DIS SIS_EN Reserved TSD_INT OVP_INT Reserved TSD_IEN OVP_IEN Reserved Law D4EN D3EN D2EN OFFT DIMT BL_FI BL_MC BL_DC SC_LAW SC4_EN SC3_EN SC2_EN SC6_OFF SC5_OFF SC2_OFF SC1_OFF SCFI SCD7 SCD6 SCD5 SCD4 SCD3 SCD2 SCD1 ADP8861 Bit 0 BL_EN FOVR D1EN SC1_EN ...
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... LEDs are off. The charge pump switches up in gain as needed. This feature is useful if the ADP8861 charge pump is used to drive an external load. This feature must be used when utilizing small fly capacitors (0402 or smaller). ...
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... OVP_IEN flag is enabled the overvoltage interrupt is enabled the overvoltage interrupt is disabled (the OVP_INT flag continues to assert). N/A [1:0] Reserved. Bit 4 Bit 3 SHORT_INT TSD_INT 1 . OVP . OVP Bit 3 Bit 2 TSD_IEN OVP_IEN Rev Page ADP8861 Bit 2 Bit 1 Bit 0 OVP_INT Reserved Bit 1 Bit 0 Reserved ...
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... ADP8861 BACKLIGHT REGISTER DESCRIPTIONS Configuration Register (CFGR)—Register 0x04 Table 16. CFGR Bit Map Bit 7 Bit 6 Table 17. Bit Descriptions for the CFGR Register Bit Name Bit No. Description N/A [7:3] Reserved Law [2:1] Backlight transfer law 00 = linear law DAC, linear time steps 01 = square law DAC, linear time steps ...
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... Bit 6 Bit 5 Bit 4 Bit 6 Bit 5 Bit 4 Rev Page Bit 3 Bit 2 Bit 1 OFFT Bit 3 Bit 2 Bit 1 DIMT ADP8861 Bit 0 Bit 0 ...
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... ADP8861 Backlight Fade (BLFR)—Register 0x08 Table 24. BLFR Bit Map Bit 7 Bit 6 Bit 5 BL_FO Table 25. Bit Descriptions for the BLFR Register Bit Name Bit No. Description BL_FO [7:4] Backlight fade out rate. If fade out is disabled (BL_FO = 0000), the backlight changes instantly (within 100 ms). If the fade out rate is set, the backlight fades from its current value to the dim or the off value ...
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... Rev Page ADP8861 Bit 2 Bit 1 Bit 0 Linear Law (mA) Square Law (mA) 8.031 2.150 8.268 2.279 8.504 2.411 8.740 2.546 8.976 2.686 9.213 2.829 9.449 2 ...
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... ADP8861 DAC Code Linear Law (mA) 0x44 16.063 0x45 16.299 0x46 16.535 0x47 16.772 0x48 17.008 0x49 17.244 0x4A 17.480 0x4B 17.717 0x4C 17.953 0x4D 18.189 0x4E 18.425 0x4F 18.661 0x50 18.898 0x51 19.134 0x52 19.370 0x53 19.606 0x54 19.842 0x55 20.079 0x56 20 ...
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... SC7 is turned SC7 is turned off This enable acts upon LED6 1 = SC6 is turned SC6 is turned off This enable acts upon LED5 1 = SC5 is turned SC5 is turned off Rev Page ADP8861 Bit 2 Bit 1 Bit 0 Bit 2 Bit 1 Bit 0 SC_LAW Bit 2 Bit 1 ...
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... ADP8861 Bit Name Bit No. SC4_EN 3 SC3_EN 2 SC2_EN 1 SC1_EN 0 Independent Sink Current Time (ISCT1)—Register 0x11 Table 35. ISCT1 Bit Map Bit 7 Bit 6 Bit 5 SCON Table 36. Bit Descriptions for the ISCT1 Register Bit Name Bit No. Description SCON [7: time. If the SCx_OFF time is not disabled and the independent current sink is enabled (Register 0x10), the LED(s) remains on for the on time selected (per the following list) and then turns off ...
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... ISC turns off for the off time (per the following listed times) and then turns on according to the SCON setting off time disabled 01 = 0.6 sec 10 = 1.2 sec 11 = 1.8 sec 1 Each current sink remains on continuously when its enable is set to 1 and its off time is set to 00 (disabled). Bit 4 Bit 3 SC3_OFF SC2_OFF 1 Rev Page ADP8861 Bit 2 Bit 1 Bit 0 SC1_OFF ...
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... ADP8861 Independent Sink Current Fade (ISCF)—Register 0x13 Table 39. ISCF Bit Map Bit 7 Bit 6 Bit 5 SCFO Table 40. Bit Descriptions for the ISCF Register Bit Name Bit No. Description SCFO [7:4] Sink current fade out rate. The following times listed are for a full-scale fade out ( mA). Fades between closer current values reduce the fade time ...
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... Rev Page ADP8861 Bit 2 Bit 1 Bit 0 Linear Law (mA) Square Law (mA) 11.81 2.326 12.28 2.514 12.76 2.712 13.23 2.916 13.70 3.128 14.17 3.348 14.65 3.574 15.12 3.81 15.59 4.052 16.06 4.3 16 ...
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... ADP8861 DAC Code Linear Law (mA) 0x32 23.62 0x33 24.09 0x34 24.57 0x35 25.04 0x36 25.51 0x37 25.98 0x38 26.46 0x39 26.93 0x3A 27.40 0x3B 27.87 0x3C 28.35 0x3D 28.82 0x3E 29.29 0x3F 29.76 0x40 30.24 0x41 30.71 0x42 31.18 0x43 31.65 0x44 32.13 0x45 32.60 0x46 33.07 0x47 33.54 0x48 34.02 0x49 34.49 0x4A 34.96 0x4B 35.43 0x4C 35.91 0x4D 36.38 0x4E 36.85 0x4F 37.32 0x50 37.80 0x51 38.27 0x52 38.74 0x53 39.21 0x54 39.69 0x55 40 ...
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... Bit 5 Bit 4 Bit 3 Linear Law (mA) Square Law (mA 0.236 0.002 0.472 0.007 0.709 0.017 … … Rev Page Bit 2 Bit 1 Bit 2 Bit 1 SCD5 Bit 2 Bit 1 SCD4 ADP8861 Bit 0 Bit 0 Bit 0 ...
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... ADP8861 Sink Current Register LED3 (ISC3)—Register 0x18 Table 50. ISC3 Bit Map Bit 7 Bit 6 Reserved Table 51. Bit Descriptions for the ISC3 Register Bit Name Bit No. Description N/A 7 Reserved. SCD3 [6:0] Sink current. Use the following DAC code schedule (see Table 28 for a complete list of values): ...
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... Body, Very Thin Quad (CP-20-10) Dimensions shown in millimeters Figure 45. Tape and Reel Orientation for LFCSP Units Rev Page 2.65 2. 0.25 MIN FOR PROPER CONNECTION OF THE EXPOSED PAD, REFER TO THE PIN CONFIGURATION AND FUNCTION DESCRIPTIONS SECTION OF THIS DATA SHEET. ADP8861 ...
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... ORDERING GUIDE 1 Model Temperature Range ADP8861ACPZ-RL −40°C to +85°C ADP8861ACBZ-R7 −40°C to +85°C ADP8861DBCP-EVALZ ADP886XMB1-EVALZ RoHS Compliant Part refers to a communications protocol originally developed by Philips Semiconductors (now NXP Semiconductors). ©2010 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners ...