Agilent ADNS-2620 Optical Mouse Sensor Data Sheet Features • Precise optical navigation technology • Small form factor (10 mm x 12.5 mm footprint) • No mechanical moving parts • Complete 2D motion sensor • Common interface for general purpose controller Description The ADNS-2620 is a new entry level, small form factor optical mouse sensor. It is used to implement a non-mechanical tracking engine for computer mice. Unlike its predecessor, this new optical mouse sensor allows for more compact and affordable optical mice designs. It is based on optical navigation technology, which measures changes in position by optically acquiring sequential surface images (frames) and mathematically determining the direction and magnitude of movement. The sensor is housed in an 8-pin staggered dual inline package (DIP). It is designed for use with the HDNS-2100 Lens, HLMP-ED80-xx000, and the HDNS-2200 LED Clip, providing an optical mouse solution that is compact and affordable. There are no moving parts, so precision optical alignment is not required, thereby facilitating high volume assembly. The output format is a two wire serial port. The current X and Y information are available in registers accessed via the serial port. • Smooth surface navigation Resolution is 400 counts per inch (cpi) with rates of motion up to 12 inches per second (ips). • 400 cpi resolution Theory of Operation The ADNS-2620 is based on Optical Navigation Technology. It contains an Image Acquisition System (IAS), a Digital Signal Processor (DSP) and a two wire serial port. • Wave solderable The IAS acquires microscopic surface images via the lens and illumination system provided by the HDNS-2100, HDNS-2200, and HLMP-ED80-xx000. These images are processed by the DSP to determine the direction and distance of motion. • Serial port registers • Programmable frame speed up to 3000 frames per sec (fps) • Accurate motion up to 12 ips • High reliability • High speed motion detector • Single 5.0 volt power supply • Conforms to USB suspend mode specifications • Power conservation mode during times of no movement – Programming – Data transfer • 8-pin staggered dual inline package (DIP) Applications • Mice for desktop PC’s, workstations, and portable PC’s • Trackballs • Integrated input devices Pin Number Pin Description 1 OSC_IN Oscillator input 2 OSC_OUT 3 4 LED_CNTL 5 Oscillator output GND 6 SDIO Serial Port Data (input and output) VDD 7 SCK Serial Port Clock (Input) REFA 8 5 LED_CNTL Digital Shutter Signal Out 6 GND System Ground 7 VDD 5V DC Input 8 REFA Internal reference A2620 XYYWWZ Pinout of ADNS-2620 Optical Mouse Sensor SCK 3 SDIO 2 OSC_OUT 1 OSC_IN Figure 1. Mechanical drawing: top view. Figure 2. Package outline drawing. CAUTION: It is advisable that normal static precautions should be taken in the handling and assembly of this component to prevent damage and/or degradation which may be induced by ESD. 2 4 Overview of Optical Mouse Sensor Assembly NOTE: Pin 1 of optical mouse sensor should be inserted into the reference point of mechanical cutouts. Figures 3 and 4 are shown with HDNS-2100, HDNS-2200 and HLMP-ED80-xx000. 28.00 1.102 18.94 0.746 9.06 0.357 1.00 0.039 Clear Zone φ 3.50 0.138 12.60 0.496 11.10 0.437 0 7.45 1.35 4.91 0.293 0.053 0.193 1.25 0.049 Agilent Technologies provides an IGES file drawing describing the base plate molding features for lens and PCB alignment. The components shown in Figure 5 interlock as they are mounted onto defined features on the base plate. 29.15 1.148 0 ALL DIMENSIONS 8X φ 0.80 0.031 13.73 0.541 MM INCH Figure 3. Recommended PCB mechanical cutouts and spacing. 32.46 1.278 (Top view) +X The ADNS-2620 sensor is designed for mounting on a through hole PCB, looking down. There is an aperture stop and features on the package that align to the lens. The HDNS-2100 lens provides optics for the imaging of the surface as well as illumination of the surface at the optimum angle. Features on the lens align it to the sensor, base plate, and clip with the LED. The lens also has a large round flange to provide a long creepage path for any ESD events that occur at the opening of the base plate. 19.10 0.752 +Y BASE PLATE Dimensions in mm/in. ESD LENS RING (Side view) 14.58 0.574 10.58 0.417 PLASTIC SPRING 13.82 0.544 7.45 0.293 PCB SENSOR 3 BASE PLATE ALIGNMENT POST Figure 4. 2D assembly drawing of ADNS-2620 shown with the HLMP-ED80 (top and side view). The HDNS-2200 clip holds the LED in relation to the lens. The LED’s leads must be formed first before inserting into the clip. Then, both LED and clip is loaded on the PCB. The clip interlocks the sensor to the lens, and through the lens to the alignment features on the base plate. The HLMP-ED80-xx000 is recommended for illumination. If used with the bin table (as shown in Figure 8), sufficient illumination can be guaranteed. CLIP HDNS-2200 (Clip) HLMP-ED80-xx000 ADNS-2620 (Sensor) Customer supplied PCB HDNS-2100 (Lens) Customer supplied base plate with recommended alignment features per IGES drawing Figure 5. Exploded view drawing. SDIO OSCILLATOR RESONATOR OSC_OUT IMAGE PROCESSOR LED CONTROL 7. Insert PCB assembly over the lens onto the base plate aligning post to retain PCB assembly. The sensor aperture ring should self-align to the lens. OSC_IN SERIAL PORT VOLTAGE REGULATOR AND POWER CONTROL SCK SERIAL PORT REFA VDD GND LED CONTROL VOLTAGE REFERENCE 8. The optical position reference for the PCB is set by the base plate and lens. Note that the PCB motion due to button presses must be minimized to maintain optical alignment. 5 VOLT POWER Figure 6. Block diagram of ADNS-2620 optical mouse sensor. PCB Assembly Considerations 1. Insert the sensor and all other electrical components into PCB. Note: Pin 1 of the sensor should always be the reference point of mechanical cutouts. 2. Bend the LED leads 90° and then insert the LED into the assembly clip until the snap feature locks the LED base. 3. Insert the LED/clip assembly into PCB. 4. Wave solder the entire assembly in a no-wash solder process utilizing solder fixture. The solder fixture is needed to protect the sensor during the solder process. The fixture should be designed to expose the sensor leads to solder while shielding the optical aperture from direct solder contact. The solder fixture is also used to set the reference height of the sensor to the PCB top during wave soldering (Note: DO NOT remove the kapton tape during wave soldering). 5. Place the lens onto the base plate. 6. Remove the protective kapton tape from optical aperture of the sensor. Care must be taken to keep contaminants from entering the aperture. It is recommended not to place the PCB facing up during the entire mouse assembly process. The PCB should be held vertically for the kapton removal process. Sensor PCB 9. Install mouse top case. There MUST be a feature in the top case to press down onto the clip to ensure all components are interlocked to the correct vertical height. Design Considerations for Improving ESD Performance The flange on the lens has been designed to increase the creepage and clearance distance for electrostatic discharge. The table below shows typical values assuming base plate construction per the Agilent supplied IGES file and HDNS-2100 lens flange. Typical Distance Millimeters Creepage 16.0 Clearance 2.1 For improved ESD performance, the lens flange can be sealed (i.e. glued) to the base plate. Note that the lens material is polycarbonate and therefore, cyanoacrylate based adhesives or other adhesives that may damage the lens should NOT be used. Clip LED Lens/Light Pipe Base Plate Surface Figure 7. Sectional view of PCB assembly highlighting optical mouse components (optical mouse sensor, clip, lens, LED, PCB and base plate). 4 0.1 µF 4.7 µF 0.1 µF 11 VDD VDD 12 D1.3 KΩ 8 GND GND QA SHLD VDD VDD 5 QB 14 R1 100K ohms HLMP-ED80-xx000 SURFACE D+ 6 GND DVreg P1.0 P1.1 RΩ P0.5 P0.6 P0.7 P0.3 P0.2 1 Internal Image Sensor P0.0 P0.1 17 3 SDIO 16 15 4 ADNS-2620 13 D+ Vpp CYPRESS CY7C63723C-PC 7 VDD HDNS 2100 Lens 7 LED_CNTL OSC_IN 5 1K ohms 2N3906 1 SCK OSC_OUT 2 4 L REFA 3 8 M R Buttons XTALOUT 10 Murata CSALS24M0X53-B0 TDK FCR24.0M2G 2.2 µF 2 Z LED VSS Ceramic Resonaator 24 MHz HLMP-ED80 Bin K L M N P Q R S T 6 XTALIN 9 6 MHz (Optional) R1 VALUE (Ohms) 32.0 32.0 32.0 32.0 32.0 to 61.2 32.0 to 73.9 32.0 to 84.4 32.0 to 103 32.0 to 130 Figure 8. Circuit block diagram for a typical corded optical mouse using an Agilent ADNS-2620 optical mouse sensor. Notes on Bypass Capacitors • Caps for pins 6,7 and 8 to ground MUST have trace lengths LESS than 5 mm. • The 0.1 uF caps must be ceramic. • Caps should have less than 5 nH of self inductance • Caps should have less than 0.2 ohms ESR • Surface mount parts are recommended 5 Regulatory Requirements • Passes FCC B and worldwide analogous emission limits when assembled into a mouse with unshielded cable and following Agilent recommendations. • Provides sufficient ESD creepage/clearance distance to avoid discharge up to 15 kV when assembled into a mouse according to usage instructions above. • Passes EN61000-4-4/IEC801-4 EFTB tests when assembled into a mouse with shielded cable and following Agilent recommendations. • For eye safety consideration, please refer to the technical report available on the web site at www.agilent.com/ semiconductors. • UL flammability level UL94 V-0. Absolute Maximum Ratings Parameter Symbol Minimum Maximum Units Storage Temperature TS -40 85 °C Operating Temperature TA -15 55 °C 260 °C V Lead Solder Temp Supply Voltage Notes For 10 seconds, 1.6 mm below seating plane VDD -0.5 5.5 2 KV All pins, human body model MIL 883 Method 3015 Input Voltage VIN -0.5 VDD + 0.5 V SDIO, CLK, LED_CNTL Input Voltage VIN -0.5 3.6 V OSC_IN, OSC_OUT, REFA ESD Recommended Operating Conditions Parameter Symbol Minimum Operating Temperature TA 0 Power Supply Voltage VDD 4.1 Power Supply Rise Time Maximum Units 40 °C 5.5 Volts VRT 100 ms Supply Noise VN 100 mV Peak to peak within 0-100 MHz bandwidth Clock Frequency fCLK 25.0 MHz Set by ceramic resonator Serial Port Clock Frequency SCLK fCLK/12 MHz Resonator Impedance XRES 55 Ω Distance from Lens Reference Plane to Surface Z 2.3 2.5 mm Results in ±0.2 mm DOF (See Figure 9) Speed S 0 12 in/sec @ frame rate = 1500 fps Acceleration A 0.25 g @ frame rate = 1500 fps Light Level onto IC IRRINC 80 100 25,000 30,000 mW/m2 λ = 639 nm λ = 875 nm SDIO Read Hold Time tHOLD 100 µs Hold time for valid data (Refer to Figure 22) SDIO Serial Write-write Time tSWW 100 µs Time between two write commands (Refer to Figure 25) SDIO Serial Write-read Time tSWR 100 µs Time between write and read operation (Refer to Figure 26) SDIO Serial Read-write Time tSRW 250 ns Time between read and write operation (Refer to Figure 27) SDIO Serial Read-read Time tSRR 250 ns Time between two read commands (Refer to Figure 27) Data Delay after PD deactivated tCOMPUTE 3.1 ms After tCOMPUTE, all registers contain data from first image after wakeup from Power-Down mode. Note that an additional 75 frames for AGC stabilization may be required if mouse movement occurred while Power Down. (Refer to Figure 10) SDIO Write Setup Time tSETUP 60 ns Data valid time before the rising of SCLK (Refer to Figure 20) Frame Rate FR frames/s See Frame_Period register section 6 23.0 Typical 5.0 24.0 2.4 1500 2300 Notes Register values retained for voltage transients below 4.10V but greater than 3.9V ADNS-2620 HDNS-2100 Z OBJECT SURFACE Figure 9. Distance from lens reference plane to surface. AC Electrical Specifications Electrical Characteristics over recommended operating conditions. Typical values at 25°C, VDD = 5 V, 24 MHz, 1500 fps. Parameter Symbol Min. Power Down (PD) tPD 1.33 Power Up after PD mode deactivated tPUPD Power Up from VDD ↑ tPU Typ. Max. Units Notes µs 32 clock cycle minimum after setting bit 6 in the Configuration register. (Refer to Figure 12) 50 ms From PD mode deactivation to accurate reports 610 µs + 75 frames (Refer to Figure 10) 40 ms From VDD to valid accurate reports 610 µs + 50 frames ns CL = 30 pF (the rise time is between 10% to 90%) Rise and Fall Times SDIO tr 30 tf 16 ns CL = 30 pF (the fall time is between 10% to 90%) Serial Port Transaction Timer tSPTT 90 ms Serial port will reset if current transaction is not complete within tSPTT (Refer to Figure 29) Transient Supply Current IDDT 20 mA Max supply current during a VDD ramp from 0 to 5.0V with > 500 µs rise time. Does not include charging current for bypass capacitors 7 37 DC Electrical Specifications Electrical Characteristics over recommended operating conditions. Typical values at 25°C, VDD = 5 V, 24 MHz, 1500 fps. Parameter Symbol Supply Current (mouse moving) Min. Typ. Max. Units IDD AVG 15 30 mA Supply Current (mouse not moving) IDD 12 Power Down Mode Current IDDPD 170 Notes mA 230 µA 0.8 V SCK pin Input Low Voltage VIL Input High Voltage VIH Input Capacitance CIN Input Resistance RIN 2.0 V 10 1 pF MΩ SDIO pin VDD=4 V, Load = 50 pF, 80n s rise & fall Input Low Voltage VIL 0.8 Input High Voltage VIH Output Low Voltage VOL Output High Voltage VOH 0.8 * VDD V Drive Low Current IL 2.0 mA Drive High Current IH 2.0 mA Input Capacitance CIN Input Resistance RIN 2.0 V V 0.5 10 1 V pF MΩ LED_CNTL pin Output Low Voltage VOL 0.1 V Output High Voltage VOH 0.8 * VDD V Drive Low Current IL 250 µA Drive High Current IH 250 µA OSC_IN 8 Input Resistance RIN 500 kΩ Input Capacitance CIN 15 pF Input High Voltage VIH Input Low Voltage VIL 2.2 0.8 V External clock source V External clock source PD Pin Timing Note: All timing circuits shown, from Figure 10 onwards, are based on the 24 MHz resonator frequency. Power Down deactivated Power Down Deactivation IDD 75 frames (610) µs t pupd tCOMPUTE (See Figure 11) Figure 10. Power up timing mode. Power Down deactivated Power Down Deactivation Oscillator Start Reset Count Initialization New Acquisition 2410 µs 250 µs 360 µs LED CURRENT SCLK 610 µs Optional SPI transactions with old image data tcompute SPI transactions with new image data At default frame rate Figure 11. Details of wake-up timing after PD. 9 Power-down Mode (PD) and Timing ADNS-2620 can be placed in a power-down mode by setting bit 6 in the configuration register via a serial I/O port write operation. Note that while writing a “1” to bit 6 of the configuration register, all other bits must be written with their original value in order to keep the current configuration. After setting the configuration register, wait at least 32 system clock cycles. To get the chip out of the power-down mode, clear bit 6 in the configuration register via a serial I/O port write operation. (CAUTION! In power-down mode, the SPI timeout (t SPTT ) will not function. Therefore, no partial SPI command should be sent. Otherwise, the sensor may go into a hang-up state). While the sensor is in power-down mode, only the bit 6 data will be written to the configuration register. Writing the other configuration register values will not have any effect. For an accurate report after power-up, wait for a total period of 50 ms before the microcontroller is able to issue any write/read operation to the ADNS-2620. The sensor register settings, prior to power-down mode, will remain during powerdown mode. CLK 32 clock cycles min SCK 1 SDIO A6 A5 A4 A3 D5 D4 D3 D2 D1 D0 IDD tPD Figure 12. Power-down timing. The address of the configuration register is 1000000. Assume that the original content of the configuration register is 0x00. SCK Write Operation 1 Configuration Register Data (0x40) Configuration Register Address 1 0 0 0 0 0 0 SDIO Figure 13. Power-down configuration register writing operation. Setting the power down bit simply sets the analog circuitry into a no current state. Note: LED_CNTL, and SDIO will be tri-stated during power down mode. 10 0 1 0 0 0 0 0 0 Typical Performance Characteristics Performance characteristics over recommended operating conditions. Typical values at 25°C, VDD = 5 V, 24 MHz, 1500 fps. Parameter Symbol Path Error (Deviation) PError Min. Typ. Max. 0.5 Units Notes % Path Error (Deviation) is the error from the ideal cursor path. It is expressed as a percentage of total travel and is measured over standard surfaces. The following graphs (Figures 14-18) are the typical performance of the ADNS-2620 sensor, assembled as shown in the 2D assembly drawing with the HDNS-2100 Lens/Prism, the HDNS-2200 clip, and the HLMPED80-xx000 (See Figure 4). 1.0 400 400 0.8 300 300 DPI RELATIVE RESPONSIVITY 500 DPI 500 200 200 Burl Formica White Paper Manila Black Copy Black Walnut 100 White Paper Manila Black Copy 100 0 1 3 z (mm) 5 7 9 11 13 15 Figure 15. Typical Resolution vs. Velocity @ 1500 fps. 600 500 100% 75% 50% 500 400 400 DPI DPI 300 300 200 200 100% 75% 50% 100 100 0 0 -1 -0.6 -0.2 0.2 0.6 1 z (mm) Figure 17. Typical Resolution vs. Height at different LED currents on manila. 11 -1 -0.6 -0.2 0.2 0 400 500 600 700 800 900 1000 WAVELENGTH (nm) VELOCITY (ips) Figure 14. Typical Resolution vs. Z (comparative surfaces) 0.4 0.2 0 -1 -0.8 -0.6 -0.4 -0.2 -0 0.2 0.4 0.6 0.8 1 0.6 0.6 1 z (mm) Figure 18. Typical Resolution vs. Height at different LED currents on black. Figure 16. Wavelength Responsivity[1]. Notes: 1. The ADNS-2620 is designed for optimal performance when used with the HLMP-ED80-xx000 (red LED 639 nm). For use with other LED colors (i.e., blue, green), please consult factory. When using alternate LEDs, there may also be performance degradation and additional eye safety considerations. 2. Z = Distance from Lens Reference plane to Surface. 3. DOF = Depth of Field. Synchronous Serial Port The synchronous serial port is used to set and read parameters in the ADNS-2620, and also to read out the motion information. SCK: The serial port clock. It is always generated by the master (the microcontroller). The port is a two wire, half duplex port. The host microcontroller always initiates communication; the ADNS-2620 never initiates data transfers. Write Operation Write operations, where data is going from the microcontroller to the ADNS-2620, is always initiated by the microcontroller and SCK Cycle # SDIO: The data line. consists of two bytes. The first byte contains the address (seven bits) and has a “1” as its MSB to indicate data direction. The second byte contains the data. The transfer is synchronized by SCK. The microcontroller changes SDIO on falling edges of SCK. The ADNS-2620 reads SDIO on rising edges of SCK. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 1 A6 A5 A4 A3 A2 A1 A0 D7 D6 D5 D4 D3 D2 D1 D0 SCK SDIO SDIO Driven by Microcontroller Figure 19. Write operation. 250 ns 250 ns SCK SDIO 250 ns, min tsetup = 60 ns, min Figure 20. SDIO setup and hold times SCK pulse width. 12 DON'T CARE Read Operation A read operation, meaning data that is going from the ADNS-2620 to the microcontroller, is always initiated by the microcontroller and consists of two bytes. The first byte that contains the address is written by the microcontroller and has a “0” as its MSB to indicate data direc- SCK Cycle # 1 tion. The second byte contains the data and is driven by the ADNS-2620. The transfer is synchronized by SCK. SDIO is changed on falling edges of SCK and read on every rising edge of SCK. The microcontroller must go to a High-Z state after the last address data bit. The ADNS-2620 will go to the High-Z state after 2 3 4 5 6 7 A6 A5 A4 A3 A2 A1 8 the last data bit. Another thing to note during a read operation is that SCK needs to be delayed after the last address data bit to ensure that the ADNS-2620 has at least 100 µs to prepare the requested data. This is shown in the timing diagrams below (See Figures 21 to 23). 9 10 11 12 13 14 15 16 D7 D6 D5 D4 D3 D2 D1 D0 SCK SDIO 0 A0 SDIO Driven by ADNS-2620 SDIO Driven by Microcontroller Detail "A" Detail "B" Figure 21. Read operation. t HOLD 250 ns, max 100 µs, min Detail "A" SCK Microcontroller to ADNS-2620 SDIO handoff 0 ns, min 60 ns, min 250 ns, max Hi-Z SDIO A0 A1 250 ns, min Figure 22. Microcontroller to ADNS-2620 SDIO handoff. Detail "B" 250 ns, min ADNS-2620 to Microcontroller SDIO handoff SCK 160 ns, max SDIO D0 R/W bit of next address Released by ADNS-2620 Figure 23. ADNS-2620 to microcontroller SDIO handoff. NOTE: The 250 ns high state of SCK is the minimum data hold time of the ADNS-2620. Since the falling edge of SCK is actually the start of the next read or write command, the ADNS-2620 will hold the state of D0 on the SDIO line until the falling edge of SCK. In both write and read operations, SCK is driven by the microcontroller. 13 Driven by microcontroller D7 160 ns, min D6 Forcing the SDIO Line to the Hi-Z State There are times when the SDIO line from the ADNS-2620 should be in the Hi-Z state. For example, if the microprocessor has completed a write to the ADNS-2620, the SDIO line will go into a Hi-Z state, because the SDIO pin was configured as an input. However, if the last operation from the microprocessor was a read, the ADNS-2620 will hold the D0 state on SDIO until a falling edge of SCK. To place the SDIO pin into a Hi-Z state, activate the power-down mode by writing to the configuration register. Then, the powerdown mode can stay activated, with the ADNS-2620 in the shutdown state, or the powerdown mode can be deactivated, returning the ADNS-2620 to normal operation. In both conditions, the SDIO line will go into the Hi-Z state. 14 PD Timing SDIO PD Activated 32 clock cycles 10 ns, max Hi-Z Figure 24. SDIO Hi-z state and timing. Another method to put the SDIO line into the Hi-Z state, while maintaining the ADNS-2620 at normal mode, is to write any data to an invalid address such as 0x00 to address 0x77. The SDIO line will go into the Hi-Z state after the write operations. Required Timing between Read and Write Commands (tsxx) There are minimum timing requirements between read and write commands on the serial port. t SWW ≥100 µs SCLK Address Data Address Write Operation Data Write Operation Figure 25. Timing between two write commands. If the rising edge of the SCK for the last data bit of the second write command occurs before the 100 µs required delay, then the first write command may not complete correctly. t SWR ≥100 µs SCK Address Data Address Write Operation Next Read Operation Figure 26. Timing between write and read commands. If the rising edge of SCK for the last address bit of the read command occurs before the 100 µs required delay, then the write command may not complete correctly. tSRW and tSRR >250 ns t1 ≥100 µs SCK Address Data Read Operation Figure 27. Timing between read and either write or subsequent read commands. The falling edge of SCK for the first address bit of either the read or write command must be 15 at least 250 ns after the last SCK rising edge of the last data bit of the previous read operation. Address Next Read or Write Operation Error Detection and Recovery 1. The ADNS-2620 and the microcontroller might get out of synchronization due to ESD events, power supply droops or microcontroller firmware flaws. 2. The ADNS-2620 has a transaction timer for the serial port. If the sixteenth SCK rising edge is spaced more than approximately 90 milliseconds from the first SCK edge of the current transaction, the serial port will reset. 3. Invalid addresses: – Writing to an invalid address will have no effect. Reading from an invalid address will return all zeros. 4. Collision detection on SDIO – The only time that the ADNS-2620 drives the SDIO line is during a READ operation. To avoid data collisions, the microcontroller should relinquish SDIO before the falling edge of SCK after the last address bit. Then the ADNS-2620 begins to drive SDIO after the next rising edge of SCK. Next, the ADNS-2620 relinquishes SDIO within 160 ns of the falling SCK edge after the last data bit. The microcontroller can begin driving SDIO any time after that. In order to maintain low power consumption in normal operation or when VDD the PD bit is set high, the microcontroller should not leave SDIO floating until the next transmission (although that will not cause any communication difficulties). 5. In case of synchronization failure, both the ADNS-2620 and the microcontroller may drive SDIO. The ADNS-2620 can withstand 30 mA of short circuit current and will withstand infinite duration short circuit conditions. 6. The microcontroller can verify a successful write operation by issuing a read command to the same address and comparing the written data to the read data. 7. The microcontroller can verify the synchronization of the serial port by periodically reading the product ID from status register (Address: 0x41). Notes on Power-up and the Serial Port The sequence in which VDD, SCK and SDIO are set during powerup can affect the operation of the serial port. The diagram below shows what can happen shortly after powerup when the microprocessor tries to read data from the serial port. This diagram shows the VDD rising to valid levels, at some point the microcontroller starts The problem occurs if the ADNS-2620 powers up before the microprocessor sets the SCK and SDIO lines to be outputs and high. The ADNS-2620 sees the raising of the SCK as a valid rising edge, and clocks in the state of the SDIO as the first bit of the address (sets either a read or a write depending upon the state). In the case of a SDIO low, a read operation will start. When the microprocessor actually begins to send the address, the ADNS-2620 already has the first bit of an address. When the seventh bit is sent by the microprocessor, the ADNS-2620 has a valid address, and drives the SDIO line high within 250 ns (see detail “A” in Figure 19 and Figure 20). This results in a bus fight for SDIO. Since the address is wrong, the data sent back will be incorrect. In the case of a SDIO high, a write operation will start. The address and data will be out of synchronization, causing the wrong data written to the wrong address. >t SPTT SCK Address = 0x41 Data = 0x0b010XXXXX SDIO Don't Care State Figure 28. Power-up serial port sequence. 16 its program, sets the SCK and SDIO lines to be outputs, and sets them high. Then, the microcontroller waits to ensure the ADNS-2620 has powered up and is ready to communicate. The microprocessor then tries to read from location 0x41, Status register, and is expecting a value of 0x0b010XXXXX. If it receives this value, then it knows that the communication to the ADNS2620 is operational. Solution One way to solve the problem is by waiting for the serial port timer to time out. Serial Port Timer Timeout VDD >t SPTT SCK Address = 0x41 Data = 0x0b010XXXXX SDIO Don't Care State Figure 29. Power-up serial port timer sequence. Power-up ADNS-2620 has an on-chip internal power-up reset (POR) circuit, which will reset the chip when VDD reaches the valid value for the chip to function. If the microprocessor waits at least tSPTT from VDD valid, it will ensure that the ADNS-2620 has powered up and the timer has timed out. This assumes that the microprocessor and the ADNS-2620 share the same power supply. If not, then the microprocessor must wait for tSPTT from ADNS-2620 VDD valid. Then when the SCK toggles for the address, the ADNS-2620 will be in sync with the microprocessor. register and the data value of 0x80. Since the reset bit is set, ADNS-2620 will reset and any other bits written into the configuration register at this time is properly written into the Configuration Register. After the chip has been reset, very quickly, ADNS-2620 will clear the reset bit so there is no need for the microcontroller to rewrite the Configuration Register to reset it. Soft Reset ADNS-2620 may also be given the reset command at any time via the serial I/O port. The timing and transactions are the same as those just specified for the power-up mode in the previous section. Resync Note If the microprocessor and the ADNS-2620 get out of sync, then the data either written or read from the registers will be incorrect. An easy way to solve this is to use watchdog timer timeout sequence to resync the parts after an incorrect read. 2. The digital section is now ready to go. It takes 3 frames for the analog section to settle. The proper way to perform soft reset on ADNS-2620 is: 1. The microcontroller starts the transaction by sending a write operation containing the address of the configuration CLK Reset Occurs here SCK 1 SDIO A6 A4 A5 A3 D5 D4 D3 D2 D1 D0 Figure 30. ADNS-2620 soft reset sequence timing. Soft reset will occur when writing 0x80 to the configuration register. SCK Write Operation 1 Configuration Register Address 1 0 0 0 0 Configuration Register Data 0 SDIO Figure 31. Soft reset configuration register writing operation. 17 0 1 0 0 0 0 0 0 0 Programming Guide Registers The ADNS-2620 can be programmed through registers, via the serial port, and configuration and motion data can be read from these registers. Register Address Notes Configuration 0x40 Reset, Power Down, Forced Awake, etc Status 0x41 Product ID, Mouse state of Asleep or Awake Delta_Y 0x42 Y Movement Delta_X 0x43 X Movement SQUAL 0x44 Measure of the number of features visible by the sensor Maximum_Pixel 0x45 Minimum_Pixel 0x46 Pixel_Sum 0x47 Pixel Data 0x48 Shutter_Upper 0x49 Shutter_Lower 0x4A Frame Period 0x4B 18 Actual picture of surface Configuration Access: Read/Write Address: 0x40 Reset Value: 0x00 Bit 7 6 5 4 3 2 1 0 Field C7 C6 C5 C4 C3 C2 C1 C0 Data Type: Bit field USAGE: The Configuration register allows the user to change the configuration of the sensor. Shown below are the bits, their default values, and optional values. Field Name Description C7 Reset 0 = No effect 1 = Reset the part C6 Power down 0 = Normal operation 1 = power down all analog circuitry C5 LED Shutter Mode 0= Shutter mode off (LED always on even if no motion up to 1 sec) 1= Shutter mode on (LED only on when electronic shutter is open) C4 – C1 Reserved C0 Forced Awake Mode 0 = Normal, fall asleep after one second of no movement (1500 frames/s) 1 = Always awake Status Access: Read Bit Field Address: 0x41 Reset Value: 0x41 7 6 5 4 3 2 1 0 ID2 ID1 ID0 Reserved Reserved Reserved Reserved Awake Data Type: Bit Field USAGE: Status information and type of mouse sensor, current state of the mouse. Field Name Description ID2 - ID0 Product ID (010 for ADNS-2620) Reserved Reserved for future Awake Mouse State 0 = Asleep 1 = Awake 19 Delta_Y Access: Read Address: 0x42 Reset Value: 0x00 Bit 7 6 5 4 3 2 1 0 Field Y7 Y6 Y5 Y4 Y3 Y2 Y1 Y0 Data Type: Eight bit 2’s complement number. USAGE: Y movement is counted since last report. Absolute value is determined by resolution. Reading clears the register. Motion -128 -127 -2 -1 0 +1 +2 +126 +127 Delta_Y 80 81 FE FF 00 01 02 7E 7F Delta_X Access: Read Address: 0x43 Reset Value: 0x00 Bit 7 6 5 4 3 2 1 0 Field X7 X6 X5 X4 X3 X2 X1 X0 Data Type: Eight bit 2’s complement number. USAGE: X movement is counted since last report. Absolute value is determined by resolution. Reading clears the register Motion -128 -127 -2 -1 0 +1 +2 +126 +127 Delta_X 80 81 FE FF 00 01 02 7E 7F 20 SQUAL Access: Read Address: 0x44 Reset Value: 0x00 Bit Field 7 6 5 4 3 2 1 0 SQ7 SQ6 SQ5 SQ4 SQ3 SQ2 SQ1 SQ0 Data Type: Upper 8 bits of a 9-bit integer. USAGE: SQUAL (Surface QUALity) is a measure of the number of features visible by the sensor in the current frame. Number of Features = SQUAL Register Value x 2. The maximum value is 255. Since small changes in the current frame can result in changes in SQUAL, variations in SQUAL when looking at a surface are expected. The graph below shows 250 sequentially acquired SQUAL values, while a sensor was moved slowly over white paper. SQUAL is nearly equal to zero when there is no surface below the sensor. SQUAL Values (White Paper) SQUAL VALUE 256 192 128 64 0 1 26 51 76 NORMALIZED SQUAL VALUE 1.50 X + 3σ X X – 3σ 1.25 1.00 0.75 0.50 0.25 0 -1.0 -0.6 -0.2 0.2 0.6 DELTA FROM NOMINAL FOCUS (mm) Figure 32. Typical Mean SQUAL vs. z (white paper). 21 1.0 101 126 151 The focus point is important and could affect the SQUAL value. Figure 32 shows another setup with various z-heights. This graph clearly shows that the SQUAL value is dependent on focus distance. Note: The data is obtained by getting multiple readings over different heights. 176 201 226 251 Maximum_Pixel Access: Read Address: 0x45 Reset Value: 0x00 Bit 7 6 5 4 3 2 1 0 Field 0 0 MP5 MP4 MP3 MP2 MP1 MP0 Data Type: Six bit number. USAGE: Maximum Pixel value in current frame. Minimum value = 0, maximum value = 63. The maximum pixel value may vary from frame to frame. Shown below is a graph of 250 sequentially acquired maximum pixel values, while the sensor was moved slowly over white paper. Max Pixel on White Paper Max pixel 64 48 32 16 0 1 16 31 46 61 76 91 106 Minimum_Pixel Access: Read 121 136 151 166 181 196 211 226 241 256 Address: 0x46 Reset Value: 0x3f Bit 7 6 5 4 3 2 1 0 Field 0 0 MP5 MP4 MP3 MP2 MP1 MP0 Data Type: Six bit number. USAGE: Minimum Pixel value in current frame. Minimum value = 0, maximum value = 63. The minimum pixel value may vary from frame to frame. Min Pixel on White Paper Min pixel 64 48 32 16 0 1 22 16 31 46 61 76 91 106 121 136 151 166 181 196 211 226 241 256 Pixel_Sum Access: Read Address: 0x47 Reset Value: 0x00 Bit Field 7 6 5 4 3 2 1 0 PS7 PS6 PS5 PS4 PS3 PS2 PS1 PS0 Data Type: Upper 8 bits of a 15-bit unsigned integer. USAGE: This register is used to find the average pixel value. It reports the upper 8 bits of a 15-bit unsigned integer, which sums all 324 pixels in the current frame. It may be described as the full sum divided by 128. The formula to calculate the average pixel value is as below: Average Pixel = Register Value x 128 / 324 = Pixel_Sum x 0.395 The maximum register value is 159 (63 x 324 / 128 truncated to an integer). The minimum is 0. The pixel sum value may vary from frame to frame. Pixel Data Access: Read/Write Bit Field Address: 0x48 Reset Value: 0x00 7 6 5 4 3 2 1 0 SOF Data_Valid PD5 PD4 PD3 PD2 PD1 PD0 Data Type: Two status bits, six bit pixel data. USAGE: Digital Pixel data. Minimum value = 0, maximum value = 63. Any writes to this register resets the pixel hardware so that the next read from the Pixel Data register will read pixel #1 and the StartOfFrame bit will be set. Subsequent reads will auto increment the pixel number. To dump a complete image, set the LED to forced awake mode, write anything to this register, then read 324 times where the DataValid bit is set. On the 325th read, the StartOfFrame bit will be set indicating that we have completed one frame of pixels and are starting back at pixel 1. It takes at least 324 frames to complete an image as we can only read 1 pixel per frame. The pixel hardware is armed with any read or write to the Pixel Data register and will output pixel data from the next available frame. So, if you were to write the Pixel Data register, wait 5 seconds then read the Pixel Data register; the reported pixel data was from 5 seconds ago. Field Name Description SOF Start of Frame 0 = Not start of frame 1 = Current pixel is number 1, start of frame Data_Valid There is valid data in the frame grabber PD5 – PD0 Six bit pixel data 23 Pixel Map (sensor is facing down, looking through the sensor at the surface) Last Pixel 18 36 54 72 90 108 126 144 162 180 198 216 234 252 270 288 306 324 17 35 53 71 89 107 125 143 161 179 197 215 233 251 269 287 305 323 16 34 52 70 88 106 124 142 160 178 196 214 232 250 268 286 304 322 15 33 51 69 87 105 123 141 159 177 195 213 231 249 267 285 303 321 14 32 50 68 86 104 122 140 158 176 194 212 230 248 266 284 302 320 13 31 49 67 85 103 121 139 157 175 193 211 229 247 265 283 301 319 12 30 48 66 84 102 120 138 156 174 192 210 228 246 264 282 300 318 11 29 47 65 83 101 119 137 155 173 191 209 227 245 263 281 299 317 10 28 46 64 82 100 118 136 154 172 190 208 226 244 262 280 298 316 9 27 45 63 81 99 117 135 153 171 189 207 225 243 261 279 297 315 8 26 44 62 80 98 116 134 152 170 188 206 224 242 260 278 296 314 7 25 43 61 79 97 115 133 151 169 187 205 223 241 259 277 295 313 6 24 42 60 78 96 114 132 150 168 186 204 222 240 258 276 294 312 5 23 41 59 77 95 113 131 149 167 185 203 221 239 257 275 293 311 4 22 40 58 76 94 112 130 148 166 184 202 220 238 256 274 292 310 3 21 39 57 75 93 111 129 147 165 183 201 219 237 255 273 291 309 2 20 38 56 74 92 110 128 146 164 182 200 218 236 254 272 290 308 1 19 37 55 73 91 109 127 145 163 181 199 217 235 253 271 289 307 First Pixel 24 Pixel Dump Pictures The following images are the output of the Pixel Data command. The data ranges from 0 for complete black, to 63 for complete white. An internal AGC circuit adjusts the shutter value to keep the brightest feature (max pixel) in the mid 50’s. (a) White Paper (b) Manila Folder (c) Burl Formica (d) USAF Test Chart 25 Shutter_Upper Access: Read Address: 0x49 Reset Value: 0x01 Bit Field 7 6 5 4 3 2 1 0 S15 S14 S13 S12 S11 S10 S9 S8 Shutter_Lower Access: Read Address: 0x4A Reset Value: 0x00 Bit 7 6 5 4 3 2 1 0 Field S7 S6 S5 S4 S3 S2 S1 S0 Data Type: Sixteen bit word. USAGE: Units are clock cycles; default value is 0x0100HEX. Read Shutter_Upper first, then Shutter_Lower. They should be read consecutively. The sensor adjusts the shutter to keep the average and maximum pixel values within normal operating ranges. The shutter value may vary with every frame. Each time the shutter changes, it changes by ±1/16 of the current value. NORMALIZED SHUTTER VALUE (Counts) 1.50 X + 3σ X X – 3σ 1.25 1.00 0.75 0.50 0.25 0 -1.0 -0.6 -0.2 0.2 0.6 1.0 DISTANCE FROM NOMINAL FOCUS (mm) Figure 33. Typical Mean Shutter vs. z (white paper). Note: This graph is obtained by getting multiple readings over different heights. 26 The maximum value of the shutter is dependent upon the clock frequency. The formula for Max shutter value = clock freq – 3476 Frame Rate For a clock frequency of 24 MHz, the following table shows the maximum shutter value. 1 clock cycle is 41.67 nsec. Max Shutter Decimal Hex Upper Lower 3000 4524 0x11AC 11 AC 1512 12397 0x306D 30 6D 369 61564 0xF07C F0 7C Frame_Period Access: Read/Write Bit Field Shutter ➜ Frames/second the maximum shutter value is: Default Max Shutter Address: 0x4b Reset Value: 0xc2 7 6 5 4 3 2 1 0 FP7 FP6 FP5 FP4 FP3 FP2 FP1 FP0 Data Type: Eight bit 2’s complement number that represents the upper 8 bits of a 16 bit counter. USAGE: The frame period counter counts up until it overflows. Units are clock cycles. The formula is: Clock Rate = Counts (decimal) → Counts (hex) → Counts (2’s complement hex) Frame Rate Frame Rate (frames/sec) Clocks/Frame Decimal Clocks/Frame (2’s complement hex) 369 65024 O2 ➜ Maximum Frame Time 1512 15872 C2 ➜ Nominal Frame Time 3000 8000 E0 Note: To optimize tracking performance on dark surfaces, it is recommended that an adaptive frame rate based on shutter value be implemented for frame rates greater than 1500. Changing the frame rate results in changes in the maximum speed, acceleration limits, and dark surface performance. Ordering Information Specify part number as follows: ADNS-2620 = 8-pin staggered dual inline package (DIP), 40 per tube. www.agilent.com/semiconductors For product information and a complete list of distributors, please go to our web site. For technical assistance call: Americas/Canada: +1 (800) 235-0312 or (916) 788-6763 Europe: +49 (0) 6441 92460 China: 10800 650 0017 Hong Kong: (+65) 6756 2394 India, Australia, New Zealand: (+65) 6755 1939 Japan: (+81 3) 3335-8152(Domestic/International), or 0120-61-1280(Domestic Only) Korea: (+65) 6755 1989 Singapore, Malaysia, Vietnam, Thailand, Philippines, Indonesia: (+65) 6755 2044 Taiwan: (+65) 6755 1843 Data subject to change. Copyright © 2005 Agilent Technologies, Inc. Obsoletes 5988-9773EN May 13, 2005 5989-3098EN