±80°/sec Yaw Rate Gyro with SPI® Interface ADIS16080 FEATURES GENERAL DESCRIPTION Complete angular rate gyroscope Z-axis (yaw rate) response SPI digital output interface High vibration rejection over wide frequency 2000 g powered shock survivability Externally controlled self test Internal temperature sensor output Dual auxiliary 12-bit ADC inputs Absolute rate output for precision applications 5 V single-supply operation 8.2 mm × 8.2 mm × 5.2 mm package RoHS-compliant The ADIS16080 is a complete angular rate sensor (gyroscope) that uses the Analog Devices, Inc. surface-micromachining process to make a functionally complete angular rate sensor with an integrated serial peripheral interface (SPI). The digital data available at the SPI port is proportional to the angular rate about the axis normal to the top surface of the package (see Figure 19). A single external resistor can be used to increase the measurement range. An external capacitor can be used to lower the bandwidth. Access to an internal temperature sensor measurement is provided, through the SPI, for compensation techniques. Two pins are available for the user to input analog signals for digitization. An additional output pin provides a precision voltage reference. Two digital self-test inputs electromechanically excite the sensor to test operation of the sensor and the signal conditioning circuits. APPLICATIONS Platform stabilization Image stabilization Guidance and control Inertial measurement units Robotics The ADIS16080 is available in an 8.2 mm × 8.2 mm × 5.2 mm 16-terminal, peripheral land grid array (LGA) package. FUNCTIONAL BLOCK DIAGRAM COUT FILT RATE ADIS16080 ±80°/s GYROSCOPE TEMPERATURE SENSOR SCLK 4-CHANNEL SPI MUX/ADC DIN CS DOUT AIN2 AIN1 REFERENCE ST1 ST2 VCC 5V COM VDRIVE 3V TO 5V 06045-001 VREF Figure 1. Rev. 0 Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781.329.4700 www.analog.com Fax: 781.461.3113 ©2006 Analog Devices, Inc. All rights reserved. ADIS16080 TABLE OF CONTENTS Features .............................................................................................. 1 Supply and Common Considerations ..................................... 11 Applications....................................................................................... 1 Increasing Measurement Range ............................................... 11 General Description ......................................................................... 1 Setting Bandwidth...................................................................... 11 Functional Block Diagram .............................................................. 1 Self-Test Function ...................................................................... 11 Revision History ............................................................................... 2 Continuous Self Test .................................................................. 11 Specifications..................................................................................... 3 Rate Sensitive Axis ..................................................................... 11 Timing Specifications .................................................................. 5 Control Register.............................................................................. 12 Absolute Maximum Ratings............................................................ 6 Serial Interface ............................................................................ 13 ESD Caution.................................................................................. 6 Second-Level Assembly ............................................................. 14 Pin Configuration and Function Descriptions............................. 7 Outline Dimensions ....................................................................... 15 Typical Performance Characteristics ............................................. 8 Ordering Guide .......................................................................... 15 Theory of Operation ...................................................................... 11 REVISION HISTORY 7/06—Revision 0: Initial Version Rev. 0 | Page 2 of 16 ADIS16080 SPECIFICATIONS TA = 25°C, VCC = VDRIVE = 5 V, angular rate = 0°/sec, COUT = 0 μF, ±1 g, unless otherwise noted. Table 1. Parameter SENSITIVITY Dynamic Range2 Initial Change over Temperature3 Nonlinearity Voltage Sensitivity NULL Initial Change Over Temperature3 Turn-On Time Linear Acceleration Effect Voltage Sensitivity NOISE PERFORMANCE Total Noise Rate Noise Density FREQUENCY RESPONSE 3 dB Bandwidth (User-Selectable)4 Sensor Resonant Frequency SELF-TEST INPUTS ST1 RATEOUT Response5 ST2 RATEOUT Response5 Logic 1 Input Voltage Logic 0 Input Voltage Input Impedance TEMPERATURE SENSOR Reading at 298 K Scale Factor 2.5 V REFERENCE Voltage Value Load Drive to Ground Load Regulation Power Supply Rejection Temperature Drift LOGIC INPUTS Input High Voltage, VINH Input Low Voltage, VINL Input Current, IIN Input Capacitance, CIN ANALOG INPUTS6 Resolution Integral Nonlinearity6 Differential Nonlinearity Offset Error Gain Error Input Voltage Range Conditions Min1 Typ Max1 Unit Full-scale range over specifications range Clockwise rotation is positive output, TA = −40°C to +85°C VCC = VDRIVE = 4.75 V to 5.25 V Best fit straight line VCC = VDRIVE = 4.75 V to 5.25 V ±80 9.21 10.24 11.26 °/sec LSB/°/sec ±5 0.15 0.7 1629 VCC = VDRIVE = 4.75 V to 5.25 V Power on to ±½°/sec of final Any axis VCC = VDRIVE = 4.75 V to 5.25 V 0.1 Hz to 40 Hz; no averaging @ 25°C COUT = 0 μF ST1 pin from Logic 0 to Logic 1 ST2 pin from Logic 0 to Logic 1 Standard high logic level definition Standard low logic level definition To common −328 +328 3.3 2048 ±85 35 2.05 ±10.24 % % of FS % of FS 2466 0.42 43 0.05 0.51 °/sec rms LSB rms °/sec /√Hz LSB rms/√Hz 40 14 Hz kHz −540 +540 −819 +819 50 LSB LSB V V kΩ 2048 6.88 LSB LSB/K 1.7 Proportional to absolute temperature 2.45 Source 0 μA < IOUT < 100 μA VCC = VDRIVE = 4.75 V to 5.25 V Delta from 25°C 2.5 100 5.0 1.0 5.0 2.55 0.7 × VDRIVE 0.3 × VDRIVE Typically 10 nA −1 +1 10 12 −2 −2 −8 −2 0 Rev. 0 | Page 3 of 16 LSB LSB ms LSB/g LSB/V +2 +2 +8 +2 VREF × 2 V μA mV/mA mV/V mV V V μA pF Bits LSB LSB LSB LSB V ADIS16080 Parameter Leakage Current Input Capacitance Full Power Bandwidth DIGITAL OUTPUTS Output High Voltage (VOH) Output Low Voltage (VOL) CONVERSION RATE Conversion Time Throughput Rate POWER SUPPLY7 VCC VDRIVE VCC Quiescent Supply Current VDRIVE Quiescent Supply Current Power Dissipation TEMPERATURE RANGE Specified Performance Min1 −1 Conditions Typ Max1 +1 20 8 ISOURCE = 200 μA ISINK = 200 μA VDRIVE − 0.2 16 SCLK cycles with SCLK at 20 MHz 4.75 2.7 VCC @ 5 V, fSCLK = 50 kSPS VDRIVE @ 5 V, fSCLK = 50 kSPS VCC and VDRIVE @ 5 V, fSCLK = 50 kSPS Tested to max and min specifications 1 5 7.0 70 40 −40 Unit μA pF MHz 0.4 V V 800 1 ns MSPS 5.25 5.25 9.0 500 V V mA μA mW +85 °C All minimum and maximum specifications are guaranteed. Typical specifications are neither tested nor guaranteed. Dynamic range is the maximum full-scale measurement range possible, including output swing range, initial offset, sensitivity, offset drift, and sensitivity drift at 5 V supplies. 3 Defined as the output change from ambient to maximum temperature or ambient to minimum temperature. 4 Frequency at which the response is 3 dB down from dc response. Bandwidth = 1/(2 × π × 180 kΩ × (22 nF + COUT)). For COUT = 0, bandwidth = 40 Hz. For COUT = 1 μF, bandwidth = 0.87 Hz. 5 Self-test response varies with temperature. 6 For VIN < VCC. 7 All at TA = −40°C to +85°C. 2 Rev. 0 | Page 4 of 16 ADIS16080 TIMING SPECIFICATIONS TA = 25°C, angular rate = 0°/sec, unless otherwise noted. 1 Table 2. Parameter fSCLK 2 VCC = VDRIVE = 5 10 20 16 × tSCLK 50 10 30 40 0.4 × tSCLK 0.4 × tSCLK 10 15/35 10 5 20 1 tCONVERT tQUIET t2 t3 3 t43 t5 t6 t7 t8 4 t9 t10 t11 t12 Unit kHz min MHz max Description ns min ns min ns max ns max ns min ns min ns min ns min/max ns min ns min ns min μs max Minimum quiet time required between CS rising edge and start of next conversion CS to SCLK setup time Delay from CS until DOUT three-state disabled Data access time after SCLK falling edge SCLK low pulse width SCLK high pulse width SCLK to DOUT valid hold time SCLK falling edge to DOUT high impedance DIN setup time prior to SCLK falling edge DIN hold time after SCLK falling edge 16th SCLK falling edge to CS high Power-up time from full power-down/auto shutdown modes 1 Guaranteed by design. All input signals are specified with tR and tF = 5 ns (10% to 90% of VCC) and timed from a voltage level of 1.6 V. The 5 V operating range spans from 4.75 V to 5.25 V. 2 Mark/space ratio for the SCLK input is 40/60 to 60/40. 3 Measured with the load circuit in Figure 3 and defined as the time required for the output to cross 0.4 V or 0.7 V × VDRIVE. 4 t8 is derived from the measured time taken by the data outputs to change 0.5 V when loaded with the circuit in Figure 3. The measured number is then extrapolated back to remove the effects of charging or discharging the 50 pF capacitor. This means that the time, t8, quoted in the timing characteristics is the true bus relinquish time of the part and is independent of the bus loading. CS t2 3 t3 5 9 WRITE LOW ADD1 ADD0 DB11 11 12 13 14 15 16 t5 t11 t8 DB10 DB4 DB3 DB2 DB1 tQUIET DB0 THREE-STATE 2 IDENTIFICATION BITS DONTC B 6 t7 t4 ZERO DOUT THREE-STATE ZERO t DIN 4 t10 DONTC ADD1 ADD0 CODING DONTC DONTC Figure 2. Gyroscope Serial Interface Timing Diagram 200µA TO OUTPUT PIN IOL 1.6V CL 50pF 200µA IOH Figure 3. Load Circuit for Digital Output Timing Specifications Rev. 0 | Page 5 of 16 DONTC DONTC 06045-002 2 06045-003 1 SCLK tCONVERT t6 ADIS16080 ABSOLUTE MAXIMUM RATINGS Table 3. Parameter Acceleration (Any Axis, Unpowered, 0.5 ms) Acceleration (Any Axis, Powered, 0.5 ms) VCC to COM VDRIVE to COM Analog Input Voltage to COM Digital Input Voltage to COM Digital Output Voltage to COM STx Input Voltage to COM Operating Temperature Range Storage Temperature Range Rating 2000 g 2000 g −0.3 V to +6.0 V −0.3 V to VCC + 0.3 V −0.3 V to VCC + 0.3 V −0.3 V to +7.0 V −0.3 V to VCC + 0.3 V −0.3 V to VCC + 0.3 V −55°C to +125°C −65°C to +150°C Stresses above those listed under the Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only; functional operation of the device at these or any other conditions above those indicated in the operational section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Drops onto hard surfaces can cause shocks of greater than 2000 g and exceed the absolute maximum rating of the device. Care should be exercised in handling to avoid damage. ESD CAUTION Rev. 0 | Page 6 of 16 ADIS16080 NC 4 DOUT 3 SCLK DIN RATE FILT VDRIVE AIN1 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS 5 6 7 8 9 AIN2 10 COM 2 11 VREF 1 12 ST2 BOTTOM VIEW (Not to Scale) 13 ST1 14 VCC 15 NC NC = NO CONNECT CS 16 06045-004 ADIS16080 Figure 4. Pin Configuration Table 4. Pin Function Descriptions Pin No. 1 Mnemonic DIN Type 1 I 2 SCLK I 3 DOUT O 4 5 6 7 NC RATE FILT VDRIVE O I S 8 AIN1 I 9 AIN2 I 10 11 12 13 14 15 16 COM VREF ST2 ST1 VCC NC CS S O I I S 1 I Description Data In. Data to be written to the control register is provided on this input and is clocked in on the falling edge of the SCLK. Serial Clock. SCLK provides the serial clock for accessing data from the part and writing serial data to the control registers. Also used as a clock source for the ADIS16080 conversion process. Data Out. The data on this pin represents data being read from the control registers and is clocked on the falling edge of the SCLK. No Connect. Buffered Analog Output. Represents the angular rate signal. External Capacitor Connection to Control Bandwidth. Power to SPI. The voltage supplied to this pin determines the voltage at which the serial interface operates. External Analog Input Channel 1. Single-ended analog input multiplexed into the on-chip trackand-hold, according to the setting of the ADD0 and ADD1 address bits (see Table 5). External Analog Input Channel 2. Single-ended analog input multiplexed into the on-chip trackand-hold, according to the setting of the ADD0 and ADD1 address bits (see Table 5). Common. Reference point for all circuitry in the ADIS16080. Precision 2.5 V Reference. Self-Test Input 2. Self-Test Input 1. Analog Power. No Connect. Chip Select. Active low. This input frames the serial data transfer and initiates the conversion process. I = input; O = output; S = power supply. Rev. 0 | Page 7 of 16 ADIS16080 TYPICAL PERFORMANCE CHARACTERISTICS 25 70 AVERAGE = 6.4mA STD. DEVIATION = 0.2mA AVERAGE = 2014.38 STD. DEVIATION = 99.3236 PERCENT OF POPULATION (%) PERCENT OF POPULATION (%) 60 20 15 10 5 50 40 30 20 8.75 9.00 –450 600 06045-008 8.50 –460 590 8.25 –470 580 8.00 –480 7.75 7.50 7.25 7.00 6.75 6.50 6.25 AVERAGE = –519.6 LSB 18 STD. DEVIATION = 21.892 LSB –40°C PERCENT OF POPULATION (%) 2070 2060 2050 2040 +25°C 2030 2020 +85°C 2010 16 14 12 10 8 6 4 ST1 (LSB) 06045-009 –490 –500 –510 –520 –530 –540 –550 5.3 –560 5.2 –570 5.1 –580 5.0 –590 4.9 06045-006 0 4.8 –600 2 VCC (V) Figure 9. Self Test 1 Histogram Figure 6. Null Level vs. Supply Voltage 25 2080 30 PART AVERAGE, VCC = 4.75V 30 PART AVERAGE, VCC = 5.00V 30 PART AVERAGE, VCC = 5.25V AVERAGE = 522.47 LSB STD. DEVIATION = 19.9086 LSB PERCENT OF POPULATION (%) 2070 2060 2050 2040 2030 2020 20 15 10 5 Figure 7. Null Level vs. Temperature 560 550 540 530 110 ST2 (LSB) Figure 10. Self Test 2 Histogram Rev. 0 | Page 8 of 16 06045-010 TEMPERATURE (°C) 90 520 70 510 50 500 30 490 10 480 –10 470 0 –30 460 2000 –50 450 2010 06045-007 NULL LEVEL (LSB) 6.00 5.75 20 2080 NULL LEVEL (LSB) 5.50 SUPPLY CURRENT (mA) Figure 8. Supply Current Histogram Figure 5. Initial Null Histogram 2000 4.7 570 NULL (LSB) 5.25 1600 1700 1800 1900 2000 2100 2200 2300 2400 2500 06045-005 0 0 5.00 10 ADIS16080 –400 600 –420 30 PART AVERAGE, TA = –40°C 580 560 SELF TEST LEVEL (LSB) –460 –480 –500 30 PART AVERAGE, TA = +25°C –520 –540 30 PART AVERAGE, TA = +85°C –560 520 500 480 460 440 –580 4.9 5.0 5.1 5.2 5.3 VCC (V) 400 –50 –30 –10 10 30 50 70 90 110 90 110 06045-015 4.8 110 TEMPERATURE (°C) Figure 11. Self Test 1 vs. Supply Voltage 06045-014 420 06045-011 –600 4.7 540 06045-016 SELF TEST LEVEL (LSB) –440 30 PART AVERAGE, VCC = 4.75V 30 PART AVERAGE, VCC = 5.00V 30 PART AVERAGE, VCC = 5.25V Figure 14. Self Test 2 vs. Temperature 600 0 30 PART AVERAGE, TA = +85°C 30 PART AVERAGE, 30 PART AVERAGE, 30 PART AVERAGE, VCC = 4.75V VCC = 5.00V VCC = 5.25V OFFSET LEVEL (LSB) SELF TEST LEVEL (LSB) –0.5 550 30 PART AVERAGE, TA = +25°C 500 –1.5 450 30 PART AVERAGE, TA = –40°C 4.8 4.9 5.0 –2.0 5.1 5.2 5.3 VCC (V) –2.5 –50 06045-012 400 4.7 –400 30 PART AVERAGE, 30 PART AVERAGE, 30 PART AVERAGE, –420 –30 –10 10 30 50 70 TEMPERATURE (°C) Figure 12. Self Test 2 vs. Supply Voltage Figure 15. ADC Offset vs. Temperature and Supply Voltage 1.0 VCC = 4.75V VCC = 5.00V VCC = 5.25V 0.9 30 PART AVERAGE, VCC = 4.75V 30 PART AVERAGE, VCC = 5.00V 30 PART AVERAGE, VCC = 5.25V 0.8 GAIN ERROR (LSB) –440 –460 –480 –500 –520 –540 0.7 0.6 0.5 0.4 0.3 0.2 –560 0.1 –580 –50 –40 –30 –20 –10 0 10 20 30 40 50 60 70 80 90 100 TEMPERATURE (°C) 06045-013 SELF TEST LEVEL (LSB) –1.0 Figure 13. Self Test 1 vs. Temperature 0 –50 –30 –10 10 30 50 70 90 TEMPERATURE (°C) Figure 16. ADC Gain Error vs. Temperature (Excluding VREF) Rev. 0 | Page 9 of 16 ADIS16080 2.486 1825 30 PART AVERAGE, TA = +25°C 2.485 1820 30 PART AVERAGE, TA = –40°C 1815 2.483 1810 2.482 30 PART AVERAGE, TA = +85°C 2.481 1805 2.480 4.8 4.9 5.0 5.1 VCC (V) 5.2 5.3 Figure 17. VREF vs. Supply Voltage 0 1000 2000 3000 4000 5000 6000 7000 000001110000010X 000001110000011X 000001110000100X 000001110000101X 000001110000110X 000001110000111X 000001110001000X 000001110001001X 000001110001010X 000001110001011X 000001110001100X 000001110001101X 000001110001110X 000001110001111X 000001110010000X 000001110010010X SAMPLES = 8192, MAX CODE = 1827, MIN CODE = 1796, SPREAD = 32, STD DEV = 4.057, MEAN = 1811.803 Figure 18. Noise Histogram Rev. 0 | Page 10 of 16 8000 3 19 39 87 249 844 1136 1303 1702 1229 924 447 150 43 13 4 06045-018 2.479 4.7 1800 06045-017 VREF LEVEL (V) 2.484 ADIS16080 THEORY OF OPERATION The ADIS16080 operates on the principle of a resonator gyro. Two polysilicon sensing structures each contain a dither frame, which is electrostatically driven to resonance. This produces the necessary velocity element to produce a Coriolis force during angular rate. At two of the outer extremes of each frame, orthogonal to the dither motion, are movable fingers that are placed between fixed pickoff fingers to form a capacitive pickoff structure that senses Coriolis motion. The resulting signal is fed to a series of gain and demodulation stages that produce the electrical rate signal output. The rate signal is then converted to a digital representation of the output on the SPI pins. The dualsensor design rejects external g forces and vibration. Fabricating the sensor with the signal conditioning electronics preserves signal integrity in noisy environments. SETTING BANDWIDTH An external capacitor can be used in combination with an onchip resistor to create a low-pass filter to limit the bandwidth of the ADIS16080 rate response. The −3 dB frequency is defined as f OUT = 1/ (2 × π × ROUT × (COUT + 0.022 μF )) where ROUT represents an internal impedance that was trimmed during manufacturing to 180 kΩ ± 1%. Any external resistor applied between the RATE pin and the FILT pin results in ROUT = (180 kΩ × R EXT ) / (180 kΩ + R EXT ) The electrostatic resonator requires 14 V to 16 V for operation. Because only 5 V is typically available in most applications, a charge pump is included on-chip. With COUT = 0 μF, a default −3 dB frequency response of 40 Hz is obtained based upon an internal 0.022 μF capacitor implemented on-chip. After the demodulation stage, there is a single-pole, low-pass filter included on-chip that is used to limit high frequency artifacts before final amplification. The frequency response is dominated by the second low-pass filter, which is set at 40 Hz. For additional bandwidth reduction options, see the Setting Bandwidth section. SELF-TEST FUNCTION Power supply noise and transient behaviors can influence the accuracy and stability of any sensor-based measurement system. When considering the power supply for the ADIS16080, it is important to understand that the ADIS16080 provides 0.2 μF of decoupling capacitance on the VCC pin. Depending on the level of noise present in the system power supply, the ADIS16080 may not require any additional decoupling capacitance for this supply. The analog supply, VCC, and the digital drive supply, VDRIVE, are segmented to allow multiple logic levels to be used in receiving the digital output data. VDRIVE is intended for the down-stream logic power supply and supports standard 3.3 V and 5 V logic families. The VDRIVE supply does not have internal decoupling capacitors. INCREASING MEASUREMENT RANGE The full-scale measurement range of the ADIS16080 is increased by placing an external resistor between the RATE pin and FILT pin, which results in a parallel connection with the internal 180 kΩ, 1% resistor. For example, a 330 kΩ external resistor gives ~50% increase in the full-scale range. This is effective for up to a 4× increase in the full-scale range (minimum value of the parallel resistor allowed is 45 kΩ). The internal circuitry headroom requirements prevent further increase in the linear full-scale output range. The trade-offs associated with increasing the full-scale range are potential increase in output null drift (as much as 2°/sec over temperature) and introducing initial null bias errors that must be calibrated. Activating both ST1 and ST2 simultaneously is not damaging. Because ST1 and ST2 are not necessarily closely matched, actuating both simultaneously can result in an apparent null bias shift. CONTINUOUS SELF TEST As an additional failure detection measure, power-on self test can be performed. However, some applications can warrant continuous self test while sensing rate. RATE SENSITIVE AXIS This is a z-axis rate-sensing device that is also called a yaw rate sensor. It produces a positive going output voltage for clockwise rotation about the axis normal to the package top, that is, clockwise when looking down at the package lid. RATE RATE AXIS LONGITUDINAL AXIS VCC = 5V 4.75V 2.5V RATE IN A1 0.25V LATERAL AXIS GND Figure 19. Rate Signal Increases with Clockwise Rotation Rev. 0 | Page 11 of 16 06045-019 SUPPLY AND COMMON CONSIDERATIONS The ADIS16080 includes a self-test feature that actuates each of the sensing structures and associated electronics in the same manner as if subjected to angular rate. It provides a simple method for exercising the mechanical structure of the sensor, along with the entire signal processing circuit. It is activated by standard logic high levels applied to inputs ST1, ST2, or both. ST1 causes a change in the digital output equivalent to typically −540 LSB, and ST2 causes an opposite +540 LSB change. The selftest response follows the viscosity temperature dependence of the package atmosphere, approximately 0.25%/°C. ADIS16080 CONTROL REGISTER The control register on the ADIS16080 is a 12-bit, write-only register. Data is loaded from the DIN pin on the falling edge of SCLK. The data is transferred on the DIN line at the same time that the conversion result is read from the part. The data transferred on the DIN line dictates the configuration for the next conversion. This requires 16 serial clocks for every data transfer. Only the information provided on the first 12 falling clock edges (after CS falling edge) is loaded to the control register. MSB denotes the first bit in the data stream. The DIN Bit Stream bit map shows the analog input channel selection options. Table 5. Channel Selection Analog Input Channel Gyroscope Temperature Sensor AIN1 Input AIN2 Input ADD1 0 0 1 1 ADD0 0 1 0 1 DIN Bit Stream MSB (11) WRITE LOW DONTC DONTC ADD1 ADD0 HIGH HIGH DONTC DONTC LOW LSB (0) CODING Table 6. Analog Input Channel Selection Options Bit 11 Mnemonic WRITE 10 9, 8 7, 6 LOW DONTC ADD1, ADD0 5, 4 3, 2 1 0 HIGH DONTC LOW CODING Comments The value written to this bit of the control register determines whether the following 11 bits are loaded to the control register or not. If this bit is a 1, the following 11 bits are written to the control register. If it is a 0, the remaining 11 bits are not loaded to the control register, and it remains unchanged. This bit should be low. Don’t care. These two address bits are loaded at the end of the present conversion sequence and select which analog input channel is to be converted in the next serial transfer. The selected input channel is decoded as shown in Table 5. The address bits corresponding to the conversion result are output on DOUT prior to the 12 bits of data. The next channel to be converted is selected by the mux on the 14th SCLK falling edge. These bits should be high. Don’t care. This bit should be low. This bit selects the type of output coding used for the conversion result. If this bit is set to 0, the output coding for the part is twos complement. If this bit is set to 1, the output coding from the part is straight binary (for the next conversion). Rev. 0 | Page 12 of 16 ADIS16080 SERIAL INTERFACE CS going low clocks out the first leading zero to be read in by the system microcontroller or DSP on the first falling edge of SCLK. The first falling edge of SCLK will also clock out the second leading zero to be read in by the microcontroller or DSP on the second SCLK falling edge, and so on. Figure 2 shows the detailed timing diagram for the serial interface to the ADIS16080. The chip select signal, CS, frames the entire data transfer, because it must be kept in a Logic 0 state to communicate with the ADIS16080. The serial clock, SCLK, provides the conversion clock and controls the transfer of information to and from the ADIS16080 during each conversion cycle. The data input, DIN, provides access to critical control parameters in the control register; and the output signal, DOUT, provides access to the ADIS16080 output data. The remaining two address bits and 12 bits are then clocked out by subsequent SCLK falling edges, beginning with the first address bit, ADD1; thus, the second falling clock edge on the serial clock has the second leading 0 provided and also clocks out Address Bit ADD1. The final bit in the data transfer is valid on the 16th falling edge, having been clocked out on the previous (15th) falling edge. The ADIS16080 offers an efficient data transfer function by supporting simultaneous READ and WRITE cycles. A data transfer cycle is started when the CS transitions to a Logic 0 state. If DIN is in a Logic 1 state during the first falling edge of the SCLK, then the next 11 SCLK cycles fill the control register with the contents on the DIN pin. The appropriate bit definitions for DIN can be found in the DIN Bit Stream bit map and Table 6. If DIN is in a Logic 0 state during the first falling edge of the SCLK, then the contents of the control register remain unchanged. Because the control register is only 12 bits wide, the contents on the DIN pin during the last four SCLK cycles are ignored. After the 16th falling edge of SCLK, the DOUT line goes back into a three-state mode. If the rising edge of CS occurs before 16 SCLKs have elapsed, the DOUT line goes back into threestate mode and the control register is not updated. Otherwise, DOUT returns to a three-state mode on the 16th SCLK falling edge, as shown in Figure 2. For the analog inputs, the CS signal initiates the data transfer and conversion process. The falling edge of CS put the track and hold into hold mode and takes the bus out of the three-state. The analog input is sampled at this point. The conversion is also initiated at this point and requires 16 SCLK cycles to complete. During this same cycle, the digital output data is clocked out on the DOUT pin. The 12 bits of data are preceded by two leading 0s and two channel address bits, ADD1 and ADD0, identifying to which channel the result corresponds (see the Reading DOUT Bit Stream bit map and Table 7). Reading DOUT Bit Stream SCLK1 LOW LOW ADD1 ADD0 DB11 DB10 DB9 DB8 DB7 DB6 DB5 DB4 DB3 DB2 DB1 Table 7. DOUT Bit Functions SCLK 1, 2 3, 4 Mnemonic LOW ADD1, ADD0 5 6 to 15 16 DB11 DB10 to DB1 DB0 Comments The outputs are low for SCLK1 and SCLK2. The address bits corresponding to the conversion result are output on DOUT prior to the 12 bits of data. See Table 5 for the coding of these address bits. Data Bit 11 (MSB). Data Bit 10 to Data Bit 1. Data Bit 0 (LSB). Rev. 0 | Page 13 of 16 SCLK16 DB0 ADIS16080 SECOND-LEVEL ASSEMBLY 6.873 2× RAMP-UP TL tL TSMAX TSMIN tS t25°C TO PEAK TIME Figure 21. Recommended Solder Reflow Profiles Table 8. Profile Feature Average Ramp Rate (TL to TP) Preheat Minimum Temperature (TSMIN) Maximum Temperature (TSMAX) Time (TSMIN to TSMAX) (tS) 0.5 BSC 16× 0.67 BSC 12× 1 BSC 16× TSMAX to TL Ramp-Up Rate Time Maintained Above Liquidous (TL) Liquidous Temperature (TL) Time (tL) 0.9315 4× Figure 20. Second Level Assembly Pad Layout 06045-020 0.9315 4× RAMP-DOWN PREHEAT 06045-021 TEMPERATURE The ADIS16080 can be attached to the second-level assembly board using Sn63 (or equivalent) or an RoHS-compliant solder. Figure 21 and Table 8 provide acceptable solder reflow profiles for each solder type. Note that these profiles may not be the optimum profile for the user’s application. In no case shall the 260°C limit be exceeded. It is recommended that the user develop a reflow profile based upon the specific application. In general, keep in mind the lowest peak temperature and shortest dwell time above the melt temperature of the solder results in less shock and stress to the product. In addition, evaluating the cooling rate and peak temperature can result in a more reliable assembly. CRITICAL ZONE TL TO TP tP TP Peak Temperature (TP) Time Within 5°C of Actual Peak Temperature (tP) Ramp-Down Rate Time 25°C to Peak Temperature Rev. 0 | Page 14 of 16 Condition Sn63/Pb37 Pb-Free 3°C/sec max 3°C/sec max 100°C 150°C 60 sec to 120 sec 150°C 200°C 60 sec to 150 sec 3°C/sec 3°C/sec 183°C 60 sec to 150 sec 240°C + 0°C/–5°C 10 sec to 30 sec 6°C/sec max 6 min max 217°C 60 sec to 150 sec 260°C + 0°C/–5°C 20 sec to 40 sec 6°C/sec max 8 min max ADIS16080 OUTLINE DIMENSIONS 8.33 8.20 SQ 8.07 1.1585 BSC PIN 1 INDICATOR 13 PIN 1 INDICATOR 16 12 1 9 4 0.797 BSC 0.873 BSC 5 8 TOP VIEW 0.227 BSC BOTTOM VIEW 0.373 BSC 7.00 TYP 030906-A 5.20 MAX SIDE VIEW Figure 22. 16-Terminal Land Grid Array [LGA] (CC-16-1) Dimensions shown in millimeters ORDERING GUIDE Model ADIS16080ACCZ 1 ADIS16080/PCBZ1 1 Temperature Range −40°C to +85°C Package Description 16-Terminal Land Grid Array (LGA) Evaluation Board Z = Pb-free part. Rev. 0 | Page 15 of 16 Package Option CC-16-1 ADIS16080 NOTES ©2006 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D06045-0-7/06(0) Rev. 0 | Page 16 of 16