ADP8860 Analog Devices, ADP8860 Datasheet
ADP8860
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ADP8860 Summary of contents
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... VDDIO nINT D2 A4 The ADP8860 allows as many as six LEDs to be independently driven (typical). A seventh LED can be driven (typical). All LEDs are programmable for minimum/max- imum current and fade in/out times via the I LEDs can also be combined into groups to reduce the processor instructions during fade in/out ...
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... ADP8860 TABLE OF CONTENTS Features .............................................................................................. 1 Applications ....................................................................................... 1 General Description ......................................................................... 1 Typical Operating Circuit ................................................................ 1 Revision History ............................................................................... 2 Specifications ..................................................................................... Timing Diagram ..................................................................... 5 Absolute Maximum Ratings ............................................................ 6 Maximum Temperature Ranges ................................................. 6 Thermal Resistance ...................................................................... 6 ESD Caution .................................................................................. 6 Pin Configurations and Function Descriptions ........................... 7 Typical Performance Characteristics ............................................. 8 Theory of Operation ...................................................................... 12 Power Stage.................................................................................. 13 Operating Modes ........................................................................ 14 Backlight Operating Levels ...
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... Rev Page 0 μ μF, C D1:D7 = −40°C to +85°C, unless A Min Typ 2.5 2.05 1. mA, 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 ADP8860 = 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 V ...
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... ADP8860 Parameter AMBIENT LIGHT SENSING COMPARATORS Ambient Light Sensor Current DAC Bit Step Threshold L2 Level Threshold L3 Level FAULT PROTECTION Startup Charging Current Source Output Voltage Threshold Exit Soft Start Short-Circuit Protection Output Overvoltage Protection Activation Level OVP Recovery Hysteresis Thermal Shutdown ...
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... C TIMING DIAGRAM SDA t LOW SCL START CONDITION Sr = REPEATED START CONDITION P = STOP CONDITION SU, DAT t t HIGH SU, STA t Sr HD, DAT 2 Figure Interface Timing Diagram Rev Page BUF HD, STA t SU, STO P S ADP8860 ...
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... Unless otherwise specified, all voltages are referenced to GND. MAXIMUM TEMPERATURE RANGES The maximum operating junction temperature (T supersedes the maximum operating ambient temperature (T ). Therefore, in situations where the ADP8860 is A(MAX) exposed to poor thermal resistance and a high power dissipation (P ), the maximum ambient temperature may need derated ...
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... C2 SDA I C Serial Data. Requires an external pull-up resistor SCL I C Clock. Requires an external pull-up resistor. 15 GND1 14 VIN 13 VOUT 12 C2+ 11 C1+ . IH(MIN) Rev Page ADP8860 ADP8860 C1+ VOUT VIN GND1 A D6/ C2+ C2– D7 CMP_IN2 B C1– SDA CMP_IN D5 ...
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... ADP8860 TYPICAL PERFORMANCE CHARACTERISTICS VIN = 3.6 V, SCL = 2.7 V, SDA = 2.7 V, nRST = 2 otherwise noted. 2 LOAD OUT 1.8 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0 1.5 2.0 2.5 3.0 3.5 4.0 V (V) IN Figure 5. Typical Operating Current 1× 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0 1.5 2.0 2.5 3.0 3.5 4.0 V (V) IN Figure 6. Typical Operating Current 2× 0.1 0.01 0.001 (V) IN Figure 7. Typical Standby μ μ μF, C ...
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... Figure 15. Typical Soft Start Current +25° +85° –40° 2.5 3.0 3.5 4.0 4 Figure 16. Typical I C Thresholds, V and V IH ADP8860 = 100mA –40°C +25°C +85°C +105°C 5.0 5.5 IN –40°C +25°C +85°C +105°C 5.0 5 +25° +85° –40° ...
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... ADP8860 1.4 1.3 1.2 1.1 1.0 0.9 0.8 0.7 2.5 3.0 3.5 4.0 V (V) IN Figure 17. Typical ALS Current GAIN = 2× 5 10mA OUT 5.3 5.2 5.1 5.0 4.9 4.8 4.7 4.6 4.5 –40 – JUNCTION TEMPERATURE (°C) Figure 18. Typical Regulated Output Voltage (V 6.0 5.8 OVP THRESHOLD 5.6 5.4 5.2 –40 – JUNCTION TEMPERATURE (°C) Figure 19. Typical Overvoltage Protection (OVP) Threshold 0.9 0.8 0.7 0.6 0.5 0.4 0.3 –40°C 0.2 +25°C 0.1 +85°C +105° ...
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... 1µ 1µ 1µ 1µF IN OUT 120mA OUT Figure 24. Typical Operating Waveforms 2× 3. 500ns/DIV 500ns/DIV Rev Page ADP8860 V (1V/DIV) OUT I (10mA/DIV (10mA/DIV) 100µs/DIV OUT Figure 25. Typical Start-Up Waveform ...
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... SDA C2 nINT D2 The ADP8860 allows up to seven LEDs to be independently driven (typical). The seventh LED can also be driven (typical). All LEDs can be individually pro- grammed or combined into a group to operate backlight LEDs. A full set of safety features including short-circuit, overvoltage, ...
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... LEDs. Because a fixed charging and discharging combination must be used, only certain multiples of gain are available. The ADP8860 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 26) and an internal switching network 1× ...
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... ADP8860 EXIT STBY STBY EXIT STARTUP 3 NOTES THE CALCULATED GAIN DOWN TRANSITION POINT. DMAX Soft Start Feature At startup (either from UVLO activation or fault/standby recovery), the output is first charged by I until it reaches about 92 This soft start feature reduces ...
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... MUST BE HIGH FOR 20µs (MAX) BEFORE SENDING I nRST IS LOW, WHICH FORCES nSTBY LOW 2 AND RESETS ALL I C REGISTERS 2× 1.5× GAIN CHANGES ONLY OCCUR WHEN NECESSARY, 1× BUT HAVE A MIN TIME BEFORE CHANGING 10µs 100µs Rev Page ADP8860 2 C COMMANDS SOFT START ...
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... ADP8860 BACKLIGHT OPERATING LEVELS Backlight brightness control operates in three distinct levels: daylight (L1), office (L2), and dark (L3). The BLV bits in Register 0x04 control the specific level in which the backlight operates. These bits can be changed manually automatic mode (CMP_AUTOEN is set high in Register 0x01), by the ambient light sensor (see the Ambient Light Sensing section) ...
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... The law bits in Register 0x04 are used to change between these algorithms. By default, the ADP8860 uses a linear algorithm (law = 00), where the backlight current increases linearly for a corresponding increase of input code. Backlight current (in millamperes) is determined by the following equation: Backlight Current (mA) = Code × ...
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... ADP8860 The backlight turns on when BL_EN = 1. The backlight turns off when BL_EN = 0. BACKLIGHT CURRENT MAX BL_EN = 1 BL_EN = 0 Figure 32. Backlight Turn On/Off While the backlight is on (BL_EN = 1), the user can change to the dim setting by programming DIM_EN = 1 in Register 0x01. If DIM_EN = 0, the backlight reverts to its maximum setting. ...
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... BL_EN = 0 BL_EN = 1 BL_EN = 0 (RE-ASSERTED) Figure 37. Fade Override Function (FOVR is High) AMBIENT LIGHT SENSING The ADP8860 integrates two ambient light sensing comparators. One of the ambient light sensing comparator pins (CMP_IN) is always available. The second pin (D6/CMP_IN2) can be activated rather than connecting an LED to D6. Activating the CMP_IN2 function of the pin is accomplished through Bit CMP2_SEL in Register CFGR ...
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... ADP8860 contains programmable hysteresis, meaning that the photo- sensor output must rise above L3_TRP + L3_HYS before L3_OUT clears. L3_CMPR is enabled via the L3_EN bit. The L3_TRP and L3_HYS values of L3_CMPR can be set between 0 μA and 137.7 μA (typical) in steps of 0.54 μA (typical). ...
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... If the fault or load step recurs, the process may repeat. An interrupt flag is set at each OVP instance. THERMAL SHUTDOWN/OVERTEMPERATURE PROTECTION If the die temperature of the ADP8860 rises above a safe limit ) should be (150°C typical), the controllers enter thermal shutdown (TSD) OUT protection mode. In this mode, most of the internal functions ...
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... ADP8860 1 VOUT < V – OVP V OVP(HYS) 0 VOUT > V OVP FAULT 1 1 VOUT < V – OVP V (HYS) OVP 0 V > V OUT OUT(REG) OVP FAULT 1 TRY TO REGULATE VOUT OUT(REG) VOUT > V OVP 1 VOUT < V – OVP V OVP (HYS > V OUT OUT(REG) ...
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... INTERRUPTS There are five interrupt sources available on the ADP8860. • Main light sensor comparator: CMP_INT sets every time the main light sensor comparator detects a threshold (L2 or L3) transition (rising or falling conditions). • Sensor Comparator 2: CMP2_INT interrupt works the same way as CMP_INT, except the sensing input derives from the second light sensor ...
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... ADP8860 APPLICATIONS INFORMATION The ADP8860 allows the charge pump to operate efficiently with a minimum of external components. Specifically, the user must select an input capacitor (C ), output capacitor (C IN and two charge pump fly capacitors (C1 and C2 μF or greater. The value must be high enough to produce a stable input voltage signal at the minimum input voltage and maximum output load μ ...
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... The ADP8860 has an integrated noise filter on the nRST pin. Under normal conditions not necessary to filter the reset line. However, if exposed to an unusually noisy signal, then it is beneficial to add a small RC filter or EXAMPLE CIRCUITS V nRST SDA SCL nINT V IN 1µF VDDIO ...
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... ADP8860 PROGRAMMING AND DIGITAL CONTROL The ADP8860 provides full software programmability to facilitate its adoption in various product architectures. The 2 default I C address is 0101010x ( during write during read). Therefore, the default write address is 0x54 and the read address is 0x55. Note the following general behavior of registers: • ...
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... BL_FI BL1_MC BL1_DC BL2_MC BL2_DC BL3_MC BL3_DC SC_LAW SC4_EN SC3_EN SC2_EN SC6OFF SC5OFF SC2OFF SC1OFF SCFI SCD7 SCD6 SCD5 SCD4 SCD3 SCD2 SCD1 L3_OUT L2_OUT L3_EN L3_OUT2 L2_OUT2 L3_EN2 PH1LEV_HIGH PH2LEV_HIGH ADP8860 Bit 0 BLEN CMP_INT CMP_IEN FOVR D1EN SC1_EN L2_EN L2_EN2 ...
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... ADP8860 Manufacturer and Device ID (MFDVID)—Register 0x00 This is a read-only register. Table 9. MFDVID Manufacturer and Device ID Bit Map Bit 7 Bit 6 Bit 5 Manufacture Mode Control Register (MDCR)—Register 0x01 Table 10. MDCR Mode Control Bit Map Bit 7 Bit 6 Bit 5 Reserved INT_CFG nSTBY Table 11 ...
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... When the CMP2_INT status bit is set after an enabled comparator trips, an interrupt is raised if the CMP2_IEN flag is enabled the second phototransistor comparator interrupt is enabled the second phototransistor comparator interrupt is disabled (the CMP2_INT flag continues to assert). Bit 3 Bit 2 TSD_INT OVP_INT 1 . OVP . OVP Bit 3 Bit 2 TSD_IEN OVP_IEN Rev Page ADP8860 Bit 1 Bit 0 CMP2_INT CMP_INT Bit 1 Bit 0 CMP2_IEN CMP_IEN ...
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... ADP8860 Bit Name Bit No. Description CMP_IEN 0 When the CMP_INT status bit is set after an enabled comparator trips, an interrupt is raised if the CMP_IEN flag is enabled the main comparator interrupt is enabled the main comparator interrupt is disabled (the CMP_INT flag continues to assert). BACKLIGHT REGISTER DESCRIPTIONS Configuration Register (CFGR)—Register 0x04 Table 16 ...
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... LED2 as independent sink connects LED2 sink to backlight enable (BL_EN). Diode 1 backlight sink enable selects LED1 as independent sink connects LED1 sink to backlight enable (BL_EN). 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 ADP8860 Bit 0 Bit 0 ...
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... ADP8860 Backlight Fade (BLFR)—Register 0x08 Table 24. BLFR Backlight Fade 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 the 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 ADP8860 Bit 2 Bit 1 Bit 0 1 Linear Law (mA) Square Law 7.323 1.787 7.559 1.905 7.795 2.026 8.031 2.150 8.268 2.279 8.504 2.411 8 ...
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... ADP8860 DAC Code Linear Law (mA) 0x3E 14.646 0x3F 14.882 0x40 15.118 0x41 15.354 0x42 15.591 0x43 15.827 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 ...
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... Linear Law (mA) Square Law (mA 0.236 0.002 0.472 0.007 0.709 0.017 … … Bit 5 Bit 4 Bit 3 BL2_MC Linear Law (mA) Square Law (mA 0.236 0.002 0.472 0.007 0.709 0.017 … … Rev Page ADP8860 Bit 2 Bit 1 Bit 0 Bit 2 Bit 1 Bit 0 ...
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... ADP8860 Backlight Level 2 (Office) Dim Current Register (BLDM2)—Register 0x0C Table 33. BLDM2 Bit Map Bit 7 Bit 6 Reserved Table 34. Bit Descriptions for the BLDM2 Register Bit Name Bit No. Description N/A 7 Reserved. BL2_DC 6:0 Backlight Level 2 (office) dim current. See Table 28 for a complete list of values. The backlight is set to the dim current value after a dim timeout or if the DIM_EN flag is set by the user ...
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... SC7 is turned on SC7 is turned off. This enable acts upon the LED6 SC6 is turned on SC6 is turned off. This enable acts upon the LED5 SC5 is turned on SC5 is turned off. Rev Page ADP8860 Bit 2 Bit 1 Bit 0 Bit 2 Bit 1 Bit 0 SC_LAW Bit 2 ...
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... ADP8860 Bit Name Bit No. SC4_EN 3 SC3_EN 2 SC2_EN 1 SC1_EN 0 Independent Sink Current Time (ISCT1)—Register 0x11 Table 43. ISCT1 Bit Map Bit 7 Bit 6 Bit 5 SCON Table 44. Bit Descriptions for the ISCT1 Register 1, 2 Bit Name Bit No. Description SCON 7 time. If the SCxOFF time is not disabled, then when the independent current sink is enabled (Register 0x10) it remains on for the on time selected (per the following list) and then turns off ...
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... To enable multiple independent sinks, set the appropriate SCx_EN bits. To create equivalent blinking and fading sequences, enable all independent sinks in one write cycle. This causes a preprogrammed sequence to start simultaneously. Bit 4 Bit 3 SC3OFF SC2OFF Rev Page ADP8860 Bit 2 Bit 1 Bit 0 SC1OFF ...
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... ADP8860 Independent Sink Current Fade (ISCF)—Register 0x13 Table 47. ISCF Bit Map Bit 7 Bit 6 Bit 5 SCFO Table 48. 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 ADP8860 Bit 2 Bit 1 Bit 0 Linear Law (mA) Square Law 9.45 1.488 9.92 1.64 10.39 1.8 10.87 1.968 11.34 2.142 11.81 2.326 12.28 2.514 12.76 2.712 13.23 2.916 13.70 3.128 14 ...
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... ADP8860 DAC Code Linear Law (mA) 0x28 18.90 0x29 19.37 0x2A 19.84 0x2B 20.31 0x2C 20.79 0x2D 21.26 0x2E 21.73 0x2F 22.20 0x30 22.68 0x31 23.15 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 ...
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... Bit 5 Bit 4 Bit 3 SCD4 Linear Law (mA) Square Law (mA 0.236 0.002 0.472 0.007 0.709 0.017 … … Rev Page ADP8860 Bit 2 Bit 1 Bit 0 Bit 2 Bit 1 Bit 0 Bit 2 Bit 1 Bit 0 ...
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... ADP8860 Sink Current Register LED3 (ISC3)—Register 0x18 Table 58. ISC3 Bit Map Bit 7 Bit 6 Reserved Table 59. 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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... This bit is the output of the L2 comparator for the second light sensor. L3_EN2 the L3 comparator is enabled for the CMP_IN2 comparator the L3 comparator is disabled for the CMP_IN2 comparator. Bit 4 Bit 3 FORCE_RD L3_OUT Bit 3 L3_OUT2 Rev Page ADP8860 Bit 2 Bit 1 Bit 0 L2_OUT L3_EN L2_EN Bit 2 Bit 1 Bit 0 L2_OUT2 L3_EN2 ...
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... ADP8860 Bit Name Bit No. Description L2_EN2 0 Note that the L3 comparator has priority over L2 the L2 comparator is enabled for the CMP_IN2 comparator the L2 comparator is disabled for the CMP_IN2 comparator. Comparator Level 2 Threshold (L2_TRP)—Register 0x1D Table 68. L2_TRP Bit Map Bit 7 Bit 6 Bit 5 Table 69 ...
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... Bit 0). The value is updated every 80 ms (when the light sensor is enabled). This is a read-only register. Bit 4 Bit 3 Bit 2 L3_TRP Bit 4 Bit 3 Bit 2 L3_HYS Bit 4 Bit 3 Bit 2 PH1LEV_LOW Rev Page ADP8860 Bit 1 Bit 0 Bit 1 Bit 0 Bit 1 Bit 0 ...
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... ADP8860 First Phototransistor Register: High Byte (PH1LEVH)—Register 0x22 Table 78. PH1LEVH Bit Map Bit 7 Bit 6 Bit 5 Reserved Table 79. Bit Descriptions for the PH1LEVH Register Bit Name Bit No. Description N/A 7:5 Reserved. PH1LEV_HIGH 4:0 13-bit conversion value for the first light sensor—high byte (Bit 12 to Bit 8). The value is updated every 80 ms (when the light sensor is enabled). This is a read-only register. Second Phototransistor Register: Low Byte (PH2LEVL)— ...
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... Dimensions shown in millimeters Rev Page 1.60 C REF D E 0.40 REF BOTTOM VIEW (BALL SIDE UP 2.65 EXPOSED 2.50 SQ PAD 2. 0.25 MIN FOR PROPER CONNECTION OF THE EXPOSED PAD, REFER TO THE PIN CONFIGURATION AND FUNCTION DESCRIPTIONS SECTION OF THIS DATA SHEET. ADP8860 ...
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... ADP8860 ORDERING GUIDE Model Temperature Range 1 ADP8860ACBZ-R7 −40°C to +85°C 1 ADP8860ACPZ-R7 −40°C to +85° RoHS Compliant Part. Package Description 20-Ball WLCSP, Tape and Reel 20-Lead LFCSP_VQ, Tape and Reel Figure 49. Tape and Reel Orientation for WLCSP Units Figure 50. Tape and Reel Orientation for LFCSP Units Rev ...
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... NOTES Rev Page ADP8860 ...
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... ADP8860 NOTES ©2009 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D07967-0-5/09(0) Rev Page ...