DATASHEET SEARCH SITE | WWW.ALLDATASHEET.COM
Document overview
- Manufacturer or author: Provided By ALLDATASHEET.COM(FREE DATASHEET DOWNLOAD SITE)
- PDF pages: 8
Technical content
Features
- Minumum mechanical alignment during installation 2 Sine/Cosine true differential outputs with 1024 periods for unit alignment Integrated highly collimated illumination system 11 digital tracks plus 2 sin/cos tracks generate precise 16 bit Gray code Ultra fast, 1 µs cycle for serial data output word equals 16 MHz On-chip interpolation and code correction to compensate for mounting tolerance MSB can be inverted for changing the counting direction Internally built in monitor track for tracking the light level Watch dog with alarm output –25°C to +85°C operating temp.
Applications
Rotary application up to 16 bit/ 360° absolute position Rotary application up to 11 bit user defined code patterns Cost effective solution for direct integration into OEM systems 2. 11 analog (A1-A11) channels which are directly digitized by precison comparators with hysterisis tracking. The digitized signals are called D1-D11. An internal correction and synchronization module allows the composition of a true 16 bit gray code by merging the data bits of 1) and 2) by still keeping the code monotony. There is a Gray code correction feature for this encoder to counter any codewheel imperfection or misalignment. This Gray code correction can be disabled/enabled by the pin KORR. The gain and offset conditioning value of the sine and cosine wave has been on-chip preset by factory. This will compensate for mechanical sensor misalignment error.
The photocurrent of the photo diodes is fed into a trans- impedance amplifier. The analog output of the amplifier has a voltage swing of (dark/ light) about 1.3 V. Every output is transformed by precision comparators into digital signals (D1-D11). The threshold is at VDD/2 (=Analog-reference), regulated by the monitor channel. Monitor Channel with LED Control at Pins LEDR and LERR The analog output signal of the monitor channel is regulated by the LED current. An internal bipolar transistor sets this level to VDD/2 (control voltage at pin LEDR). Thus the signal swing of each output is symmetrical to VDD/2 (=Analog-reference) The error bit at pin LERR is triggered if the Ve of the internal bipolar transistor is larger than VDD/2. Signals Channels A0, A09 with Signal Conditioning and Self Calibration These two channels give out a sine and cosine wave which are 90 deg phase shifted. These signals have amplitudes which are almost constant due to the LED current monitoring. Due to amplifier mismatch the signals do have gain and offset errors. These errors are eliminated by an adaptive signal conditioning circuitry. The conditioning values are on-chip preprogrammed by factory. The analog output signals of A0 and A09 are supplied as true-differential voltage with a peak to peak value of 2.0 V at the pins A09P, A09N, A0P, A0N. Interpolator for Channels A0,A09 The interpolator generates the digital signals D0,D09 and D-1 to D-4. The interpolated signals D-1 to D-4 extend the 12 bit Gray code of the signals D11….D0 to form a 16 bit Gray code. D0 and D09 are digitized from A0 and A09. The channels A0- A11 and A09 have very high dynamic bandwidth, which allows a real time monotone 12 bit Gray code at 12000 RPM. The interpolated 16 bit Gray code can be used up to 1000 RPM only. At more than 1000 RPM, only the 12 bit Gray code from the MSB side can be used. LSB Gray Code Correction (Pin KORR) This function block synchronizes the switching points for the 11 bit gray code of the digital signals D1 to D11 with D0 and D09 (digitized signal of A0 and A09). This Gray code correction only works for the 12 bit MSB(4096 steps per revolution). It does not work for the 4 excess interpolated bits of the 16 bit Gray code. When some special applications require code patterns other than Gray code, the Gray code correction can be disabled by putting pin KORR = 0. When that happens just the 11 data bits (D1…D11) will be sent 1:1 to the DOUT serial output. Gray code correction can be switched on or off by putting the pin KORR =1 (on) or =0 (off). MSBINV and DOUT Pins The serial interface consists of a shift register. The most significant bit, MSB (D11) will always be sent first to DOUT. The MSB can be inverted (change code direction) by using pin MSBINV. DIN and NSL Pins The Serial input DIN allows the configuration as ring register for multiple transmissions or for cascading 2 or more encoders. DIN is the input of the shift register that shifts the data to DOUT. The NSL pin controls the shift register, to switch it between load (1) or shift (0) mode. Under load mode, DOUT will give the logic of the MSB, i.e., D11. Under shift mode (0), coupled with the SCL, the register will be clocked, and gives out the serial word output bit by bit. As the clock frequency can be up to 16 MHz, the transmission of the full 16 bit word can be done within 1µs. Valid data of DOUT should be read when the SCL clock is low. Please refer to timing diagram (Figure 2).
No. Pin Name Description Function Notes [1]
1 NC Internally connected to cathode of LED Do not use
2 KORR Digital-input 1 = Gray Code Correction Active CMOS, internal pu
3 PROBE_ON Digital-Input Do not use CMOS, internal pd
4 PCL Digital Input Do not use CMOS, internal pu
5 STCAL Digital Input To be ground CMOS, internal pd
6 MSBINV Digital-Input 1 = MSB inverted CMOS, internal pd
7 DIN Digital Input Shift Register input. Used for cascading only CMOS, internal pd
8 NSL Digital-Input Sh ift-register Shift (=0) / Load (=1) Control CMOS, internal pu
9 SCL Digital-Input Shift-register Shift Clock CMOS, internal pu
10 DOUT Digital Output Shift-Register Data Out (MSB first) CMOS, 2 mA
11 DO Digital Output DO signal CMOS, 2 mA
12 DPROBE Digital Output DO9 signal CMOS, 2 mA
13 VDD Supply Voltage +5 V Supply Digital
14 GND Gnd for supply voltage GND for 5 V supply analog/digital
15 A09P Analog output A09 positive (+True diff.) CMOS, analog out
16 GND Gnd for supply voltage GND for 5 V supply analog/digital
17 A0P Analog Output A0 positive (+True diff.) CMOS, analog out 18 A09N Analog output A09 negative (–True diff.) CMOS, analog out
19 VDDA Supply Voltage +5 V Supply Analog
20 A0N Analog Output A0 negative (–True diff.) CMOS, analog out
21 LERR Digital Output IR-LED Current Limit Signal CMOS, 2 mA
22 LEDR Analog Output Do not use CMOS, analog out
Note: 1. Internal pu/pd = internal pull-up (typ. 50 µA)/ pull-down (typ. 10 µA) CMOS-transistor-Rs. Pinout Configuration ESD WARNING: HANDLING PRECAUTIONS SHOULD BE TAKEN TO AVOID STATIC DISCHARGE
Figure 1. Schematic using AEAS-7000. VDD and VDDA pins as possible. D09, the digitized signal of A09. significant bit (D11) first.
Figure 2. Timing diagram.
3 Operating Temperature T A –25 +85 °C
4 Storage Temperature T S –40 +100 °C
2 Operating Temperature T A –25 25 +85 °C
1 FRAME = 16 BITS
Electrical Characteristics (VD = 4.5 to 5 V, TA = –40 to +85 °C) No. Parameters Symbol Conditions Min. Typ. Max. U nits Operating Currents
1 Total Current I total 25 mA
1 Pull Down Current Ipd –20 –5 µA
2 Pull Up Current Ipu 30 160 µA
1 Ouput-H-Level Voh Ioh = 2 mA VD - 0.5 V VD V 2 Output-L-Level Vol Iol = –2 mA 0 0.5 V Serial Interface
1 SCL Clock Frequency fclock 16 MHz
2 Duty Cycle Fclock T clock,LH Fclock = 16 MHz 0.4 0.6 ns
3 Accuracy (1) Fclock = 5MHz, ±2bits
RPM = 80 Analog-Signal-Conditioning – Signaltracks A0P, A0N,A09P,A09N 1. Signal Frequency A0, A09 Fsine,cos 0 250 KHz Note 1: Accuracy would be influenced by installation control and the bearing and shaft type being used. Test conditions to determine Accuracy 1) 80 RPM 2) 25 oC, room temperature 3) At nominal radial, tangential and gap position 4) On dual preloaded bearing with absolute assembly concentricity of not exceedding 10 microns 5) SCL frequency of 5MHz 6) Both VDD & VDDA filter capacitor placed not more than 20mm from header pins 7) Tested for one revolution
Note: Codewheel mounting tolerances for radial, tangential and Z gap are: Radial: ±50 um Tangential: ±40 um Z Gap: ±50 um UNLESS SPECIFIED OTHERWISE DIMENSIONS ARE IN MILLIMETRES THIRD ANGLE PROJECTION STRIKE OUT OR FILL IN AS NEEDED XX. XX.X XX.XX 0.3 0.1 0.03 21.2 Ø56 24.1 24.0 Ø8.02 H6 Ø42.118.85±0.2 22.6 1.5 3.65 0.35 +0.15 -0.10 (Z gap between code disc and reticle) 9.2 35.1 12.0 Ø3.2 (2x) Readhead Code Disc 2x11 -1.27mm pitch pin header Mounting Consideration
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/Interna- tional), 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 © 2004 Agilent Technologies, Inc. February 23, 2004 5988-9627EN Plug & Play Hub-Shaft design The following details the design of the hub-shaft of which the dimensions must be strictly followed for the plug & play feature of the AEAS-7000 to work. In order to secure the code disk to the hub, an adhesive must be utilised. Agilent recommends using DELO- DUOPOX, 1895 from DELO. Stainless steel is recommended as the hub-shaft material. AEA Legend 1 = 5V G = gray code S = serial output mode - 7000 - 1 G S S - Standard (-25°C to +85°C) D - 13 bits G - 16 bits
Ordering Information
A complete instruction for AEAS-7000 Plug & Play installation consideration can be found in AEAS-7000 application note. Ø12 0.8 depth as adhesive reservoir 58 Ø16 Ø15 Ø11 0.01 A 0.02 0.01 A 0.02 Ø0.01 4.2 0.01 A Ø18 Ø10h6 Ø8.02h6 +0.03 - 0.01 - 0.01 ( ) ( ) Motor end is user specified Straightness Flatness Perpendicularity Total Run-out