ADP5520 Analog Devices, ADP5520 Datasheet
ADP5520
Specifications of ADP5520
Related parts for ADP5520
ADP5520 Summary of contents
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... SCL 4 SDA 3 nINT 15 nRST The ADP5520 can detect ambient light levels and adjust the backlight brightness accordingly, resulting in extended battery operation. Once configured, the ADP5520 is capable of controlling the 2 C®- flip/slider backlight intensity, on/off timing, dimming, and fading without the intervention of the main processor, which results in valuable battery power saving ...
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... ADP5520 TABLE OF CONTENTS Features .............................................................................................. 1 Applications ....................................................................................... 1 Typical Operating Circuit ................................................................ 1 General Description ......................................................................... 1 Revision History ............................................................................... 2 Specifications ..................................................................................... Timing Specifications ............................................................ 4 Absolute Maximum Ratings ............................................................ 5 Thermal Resistance ...................................................................... 5 ESD Caution .................................................................................. 5 Pin Configuration and Function Descriptions ............................. 6 Typical Performance Characteristics ............................................. 7 Theory of Operation ........................................................................ 9 Backlight Drive and Control ....................................................... 9 Backlight Operating Levels ....................................................... 10 Backlight Maximum and Dim Settings ...
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... VDDIO 2 0.7 × VDDIO 2 0 100 0 VDDIO − 0.2 0.4 2 0.1 1 0.1 1 10 150 10 = 25⁰C, VBAT = 3 ADP5520 Unit μA μA μA mA mΩ mA/ μA μ μA μA mA kΩ °C °C ...
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... ADP5520 TIMING SPECIFICATIONS Table 2. Parameter 2 Delay from Reset Deassertion Access f SCL t HIGH t LOW t SU, DAT t HD, DAT t SU, STA t HD, STA t BUF t SU, STO the total capacitance of one bus line in picofarads. B SDA t LOW ...
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... Table 4. Thermal Resistance −0 +30 V Package Type −0 24-Lead LFCSP (CP-24-2) −0 +0.3 V ESD CAUTION 1 −40°C to +85°C −40°C to +125°C −65°C to +150°C JEDEC J-STD-020 ), using the following JA Rev Page ADP5520 θ Unit JA 50 °C/W ...
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... Overvoltage Monitor Input for the Boost Converter. 23 BL_SNK Backlight Current Sink. 24 GND Ground. PIN 1 INDICATOR PGND 1 18 GND 17 CMP_IN VDDIO nINT 3 ADP5520 SDA 4 15 nRST TOP VIEW SCL 5 14 ILED (Not to Scale NOTES 1. EXPOSED PAD MUST BE CONNECTED TO GROUND. Figure 3. Pin Configuration Rev Page ...
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... Figure 7. Standby Supply Current vs. VBAT 0.5 Figure 8. Typical Auxiliary LED Pin (R3, C3, or ILED), Full-Scale Sink Current vs. 30 Rev Page ADP5520 TEMP = –40°C TEMP = +85°C 3.5 4.0 4.5 5.0 5.5 6.0 VBAT (V) 1.0 1.5 2.0 2.5 3.0 AUX LED PIN VOLTAGE (V) Applied Pin Voltage ...
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... ADP5520 SW 1 INDUCTOR CURRENT 2 BST BL_SNK 3 4 CH1 20.0V CH2 500mA TIME (4µs/DIV) CH3 10.0V CH4 1.0V Figure 9. Boost Operation (Backlight = 30 mA INDUCTOR CURRENT 2 BST BL_SNK 3 4 CH1 20.0V CH2 500mA TIME (4µs/DIV) CH3 10.0V CH4 1.0V Figure 10. Boost Operation (Backlight = 15 mA INDUCTOR CURRENT ...
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... ADP5520 18 GND GND GND The ADP5520 is a backlight white LED driver with an I/O port expander ideal for cell phone designs and other portable devices, where keypad and/or extended I/O functionality is needed. Programmable fade-in, fade-out, dim, and off timers provide the backlight with flexible control features. Using an ...
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... Backlight Operating Levels section. This 7-bit resolution allows the user to set the backlight 128 different levels between 0 mA and 30 mA. The ADP5520 can BL_EN implement two distinct algorithms to achieve a linear and a ...
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... When the off timer expires, the internal state machine clears the BL_EN bit, and the backlight turns off. BACKLIGHT CURRENT MAX SET BY USER SET BY INTERNAL STATE MACHINE Rev Page ADP5520 DIM TIMER DIM TIMER RUNNING RUNNING DIM_EN = 1 DIM_EN = 0 DIM_EN = 1 BL_EN = 0 ...
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... Figure 21. Dim and Off Timers Used Together LINEAR BACKLIGHT FADE IN AND FADE OUT To counteract the abrupt visual effect of near instant turn-on and turn-off of the backlight, the ADP5520 contains timers to facilitate the smooth fading between off, on, and dim states. By default (BL_LAW = 00), the ADP5520 implements a fading scheme using the linear backlight code algorithm (see Equation 1) ...
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... FADE-IN TIME (s) Figure 27. Square Law Fade-In Times 30.0 27.5 25.0 22.5 20.0 17.5 15.0 12.5 10.0 7.5 5.0 2 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 FADE-OUT TIME (s) Figure 28. Square Law Fade-Out Times ADP5520 2.1 SEC 2.4 SEC 2.7 SEC 3.0 SEC 3.5 SEC 4.0 SEC 4.5 SEC 5.0 SEC 5.5 SEC 4.5 5.0 5.5 0.3 SEC 0.6 SEC 0.9 SEC 1.2 SEC 1.5 SEC 1.8 SEC 2.1 SEC 2.4 SEC 2.7 SEC 3.0 SEC 3.5 SEC 4.0 SEC 4.5 SEC 5.0 SEC 5.5 SEC 4.5 5.0 5.5 ...
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... UNIT FADE TIME Figure 30. Fade Law Comparison Over a Unit Fade Time AMBIENT LIGHT SENSING The ADP5520 can be used in conjunction with an external photosensor to detect when ambient light conditions have dropped below programmable set points. An ADC samples the output of the external photosensor. The ADC result is fed into two programmable trip comparators. The ADC has an input range of 0 μ ...
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... Rev Page VDDIO Dx_PULL Dx_IN_DBNC Dx_IN DEBOUNCE VDDIO GPIO (Rx/Cx) Dx_OUT Dx_DIR Figure 33. Typical GPIO Block Dx_IN INTERRUPT REG 0x1C CONDITION READ TWICE DECODE TO CLEAR Dx_IN_ISTAT AND Figure 34. GPIO Interrupt generation ADP5520 REG 0x00 WRITE 1 TO CLEAR nINT GPI_INT DRIVE ...
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... ADP5520 To configure the device for key scanning and decoding, the R0, R1, R2, and R3 pull-ups must be enabled in Register 0x1F. Key scanning and decoding is then enabled by programming the row and column bits in Register 0x17. The row pull-ups must be enabled before enabling key scanning. Figure 35 shows the row and column pins connected to a typical 4 × ...
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... The LEDx_CURRENT registers are six bits wide, allowing the user to set the LED sink current to one of 64 different levels between 0 mA and 14 mA. The ADP5520 can implement two distinct algorithms, to achieve a linear and a nonlinear relationship between input code and sink current. ...
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... Fade-in times represent the time it takes to fade from mA. Fade-out times represent the time it takes to fade from mA. Fading between intermediate settings is shorter. The fade timers should be programmed before asserting LEDx_EN. By default (LED_LAW = 0), the ADP5520 implements a fading scheme using the linear algorithm (see Equation 3 ...
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... KEY PRESS INTERRUPTS KEY RELEASE INTERRUPTS OVERVOLTAGE INTERRUPT RESET INPUT (nRST) The ADP5520 can be restored to a power-on reset state if the nRST pin is held low. nRST contains a debounce circuit, so the pin must be held low for greater than 75 μs (typical) before a FADE-OUT reset occurs. ...
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... The cycle continues with a repeat start, followed by the chip read address (0x65). 6. The ADP5520 acknowledges the chip read address byte by pulling the data line low. 7. The ADP5520 places the contents of the previously addressed register on the bus for readback. ...
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... Read-only register. Contains interrupt status information for key releases on Key A through Key H. 0x23 KR_INT_STAT_2 Read-only register. Contains interrupt status information for key releases on Key I through Key P. 0x24 KEY_STAT_1 Read-only register. Reflects the present state of Key A through Key H. 0x25 KEY_STAT_2 Read-only register. Reflects the present state of Key I through Key P. Rev Page ADP5520 ...
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... ADP5520 DETAILED REGISTER DESCRIPTIONS If one of the interrupt bits in Table 8 is cleared and there is a pending interrupt, nINT deasserts for 50 μs and reasserts, but the status of the pending interrupt stays set. Table 8. Register 0x00, Device Mode and Status (MODE_STATUS) Bit Mnemonic R/W 7 nSTNBY ...
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... Backlight dim timer (timer should be set before BL_EN is set). 0000 = timer disabled. 0001 = 10 sec. 0010 = 15 sec. 0011 = 20 sec. 0100 = 25 sec. 0101 = 30 sec. 0110 = 35 sec. 0111 = 40 sec. 1000 = 50 sec. 1001 = 60 sec. Rev Page ADP5520 ...
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... ADP5520 Bit Mnemonic R/W Table 12. Register 0x04, Backlight Fade-In and Fade-Out Timers (BL_FADE) Bit Mnemonic R BL_FO R BL_FI R/W Table 13. Register 0x05, Level 1 (Daylight) Maximum Current (DAYLIGHT_MAX) Bit Mnemonic R DAYLIGHT_MAX R/W Description 1010 = 70 sec. 1011 = 80 sec. 1100 = 90 sec. 1101 = 100 sec. ...
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... L3_CMPR comparator has detected a change in ambient light from Level 2 (office) to Level 3 (dark ambient light is greater than Level 2 (office L2_CMPR comparator has detected a change in ambient light from Level 1 (daylight) to Level 2 (office disable Comparator L3_CMPR enable Comparator L3_CMPR. If automatic backlight adjustment is required, BL_AUTO_ADJ must be set also. Rev Page ADP5520 ...
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... ADP5520 Bit Mnemonic R/W 0 L2_EN R/W Table 21. Register 0x0D, Level 2 (Office) Comparator Trip Point (L2_TRIP) Bit Mnemonic R L2_TRIP R/W Table 22. Register 0x0E, Level 2 (Office) Comparator Hysteresis (L2_HYS) Bit Mnemonic R L2_HYS R/W Table 23. Register 0x0F, Level 3 (Dark) Comparator Trip Point (L3_TRIP) Bit Mnemonic R ...
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... LED fade-in timer (timer should be set before LED x_EN is enabled). 0000 = timer disabled. 0001 = 0.3 sec. 0010 = 0.6 sec. 0011 = 0.9 sec. 0100 = 1.2 sec. 0101 = 1.5 sec. 0110 = 1.8 sec. 0111 = 2.1 sec. 1000 = 2.4 sec. 1001 = 2.7 sec. 1010 = 3.0 sec. 1011 = 3.5 sec. 1100 = 4.0 sec. 1101 = 4.5 sec. 1110 = 5.0 sec. 1111 = 5.5 sec. Rev Page ADP5520 ...
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... ADP5520 Table 28. Register 0x14, LED 1 Sink Current (LED1_CURRENT) Bit Mnemonic R LED1_CURRENT R/W Table 29. Register 0x15, LED 2 Sink Current (LED2_CURRENT) Bit Mnemonic R LED2_CURRENT R/W Table 30. Register 0x16, LED 3 Sink Current (LED3_CURRENT) Bit Mnemonic R LED3_CURRENT R/W Table 31. Register 0x17, GPIO Configuration 1 (Pin Configuration) (GPIO_CFG_1) ...
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... D5 input to generate interrupts on nINT prevents D4 input from generating interrupts on nINT allows D4 input to generate interrupts on nINT prevents D3 input from generating interrupts on nINT allows D3 input to generate interrupts on nINT prevents D2 input from generating interrupts on nINT allows D2 input to generate interrupts on nINT. Rev Page ADP5520 ...
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... ADP5520 Bit Mnemonic R/W 1 D1_IN_IEN R/W 0 D0_IN_IEN R/W Table 36. Register 0x1C, GPIO Interrupt Status (GPIO_INT_STAT) Bit Mnemonic R/W 7 D7_IN_ISTAT R 6 D6_IN_ISTAT R 5 D5_IN_ISTAT R 4 D4_IN_ISTAT R 3 D3_IN_ISTAT R 2 D2_IN_ISTAT R 1 D1_IN_ISTAT R 0 D0_IN_ISTAT R Table 37. Register 0x1D, GPIO Interrupt Level Configuration (GPIO_INT_LVL) Bit Mnemonic R/W 7 D7_ILVL R/W 6 D6_ILVL ...
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... Key B press. Bit cleared on read interrupt detected interrupt due to Key C press. Bit cleared on read interrupt detected interrupt due to Key D press. Bit cleared on read interrupt detected interrupt due to Key E press. Bit cleared on read. Rev Page ADP5520 ...
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... ADP5520 Bit Mnemonic R/W 2 KP_F_ISTAT R 1 KP_G_ISTAT R 0 KP_H_ISTAT R Table 41. Register 0x21, Key Press Interrupt Status 2 (KP_INT_STAT_2) Bit Mnemonic R/W 7 KP_I_ISTAT R 6 KP_J_ISTAT R 5 KP_K_ISTAT R 4 KP_L_ISTAT R 3 KP_M_ISTAT R 2 KP_N_ISTAT R 1 KP_O_ISTAT R 0 KP_P_ISTAT R Table 42. Register 0x22, Key Release Interrupt Status 1 (KR_INT_STAT_1) ...
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... Key L is currently released Key L is currently pressed Key M is currently released Key M is currently pressed Key N is currently released Key N is currently pressed Key O is currently released Key O is currently pressed Key P is currently released Key P is currently pressed. Rev Page ADP5520 ...
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... ADP5520, damage to the device can occur. The ADP5520 boost converter has an OVP limit (typical). The ADP5520 also has a feature that ramps down the backlight code when an OVP condition is detected. This may be useful in conditions where LEDs with marginally high forward voltages are used in low ambient conditions ...
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... Component Selection The ADP5520 boost converter is designed for use with a 4.7 μH inductor. Choose an inductor with a sufficient current rating to prevent it from going into saturation. The peak current limit of the ADP5520 is 750 mA (maximum), so choose an inductor with a greater saturation rating. To maximize efficiency, choose an inductor with a low series resistance (DCR). ...
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... Figure 55. I/O Configuration Example 3 1µF VBAT 4.7µH 1µ BST 1 PGND 21 VBAT 16 VDDIO ADP5520 5 SCL 4 SDA 3 nINT 15 nRST Figure 56. I/O Configuration Example 4 ...
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... ILED VBAT Figure 59. I/O Configuration Example 7 1µF 4.7µH 1µ BST BL_SNK 1 PGND CAP_OUT 21 VBAT 16 VDDIO GND GND ADP5520 5 SCL GND 4 SDA 3 nINT CMP_IN 15 nRST ILED I/O PORT UNUSED Figure 60 ...
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... ADP5520 OUTLINE DIMENSIONS PIN 1 INDICATOR 1.00 12° MAX 0.85 0.80 SEATING PLANE ORDERING GUIDE 1 Model Temperature Range ADP5520ACPZ-RL −40°C to +85°C ADP5520-EVALZ RoHS Compliant Part. 0.60 MAX 4.00 BSC SQ 0.60 MAX 19 18 0.50 BSC TOP 3.75 EXPOSED VIEW BSC SQ (BO TT OMVIEW) 0.50 13 0.40 12 0.30 0.80 MAX 2.50 REF 0.65 TYP 0.05 MAX 0.02 NOM ...
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... NOTES Rev Page ADP5520 ...
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... ADP5520 NOTES ©2008–2010 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D07445-0-1/10(A) Rev Page ...