iC-OV 5-Bit Optical Encoder
9Pages

5..25V +5V iC-OV THERMAL SHUTDOWN LOW VOLTAGE BIAS ERROR TRACK1 TRACK2 2 2 1 1 TRACK3 TRACK4 TRACK5 LED-CURRENT CONTROL DREF DDC MONITOR (see TRACK2) (see TRACK2) (see TRACK2) 1 c2 TEST 1 c2 100nF CB RSET 14k LED RNER 10k RLED 47 VCC GND LED C5 C4 C3 C2 C1 NER NINV TREF AGND ISET 8 1 7 6 5 4 3 13 10 2 9 14 11 12 TNRF BLCC OVC3 IS Vref 1.0 0.5 iC-OV 5-BIT OPTO ENCODER FEATURES APPLICATIONS ° High synchronism and technical reliability due to monolithic construction plus integrated photodiodes ° Short track pitch (600 ìm) ° Scanning with constant-light evaluation ° Photoelectric amplifier with high cut-off frequency ° Current comparators with hysteresis ° Current-limited TTL-compatible push-pull outputs ° Adjustable LED current control for constant receive power ° Integrated 40mA driver for the LED ° Integrated test aid ° Output of track 1 can be inverted to change the counting direction during Gray Code scanning ° Overtemperature circuit-breaker with hysteresis ° Detection and fault message when the safe operating range is exceeded, as the result of undervoltage, over-temperature or an LED current outside the control range ° Low power consumption ° Scanning with constant-light evaluation in absolute and multiturn rotary encoders CHIP 3.6mm × 2.9mm BLOCK DIAGRAM © 2000 Rev C0 iC-Haus GmbH Tel +49-6135-9292-0 Integrated Circuits Fax +49-6135-9292-192 Am Kuemmerling 18, D-55294 Bodenheim http://www.ichaus.com

iC-OV 5-BIT OPTO ENCODER Rev C0, 2/9 DESCRIPTION The device iC-OV is an optoelectronic encoder IC for absolute linear or angle measuring systems, e.g. glass scales or rotary encoders. Photodiodes, amplifiers, comparators and TTL-compatible push-pull output drivers for 5 tracks are monolithically integrated, as well as a reference photodiode to control the LED current. The track pitch is 600 ìm. The outputs switch to high when the amplified photoelectric currents exceed a preset threshold (constant-light evaluation). The operating point is determined by an external resistor at RSET. This...

iC-OV 5-BIT OPTO ENCODER Rev C0, Page 3/9 CHIP LAYOUT dimensions in ìm; chip size 3.6mm x 2.9mm PAD DESCRIPTION Name Function LED LED Current Control Output GND Ground C1 Track 1 Push-Pull Output C2 Track 2 Push-Pull Output C3 Track 3 Push-Pull Output C4 Track 4 Push-Pull Output C5 Track 5 Push-Pull Output VCC +5V Supply Voltage TREF Test Aid for photodiode DREF TNRF Test Aid for tracks 1 to 5 and compensation DDC ISET LED Current Control Setup AGND Reference Ground for ISET circuitry NER Error Message Output, low active NINV Track 1 Invert Mode Input, low active

iC-OV 5-BIT OPTO ENCODER Rev C0, Page 4/9 All voltages are referenced to ground unless otherwise noted. All currents into the device pins are positive; all currents out of the device pins are negative. ABSOLUTE MAXIMUM RATINGS Values beyond which damage may occur; device operation is not guaranteed. Item Symbol Parameter Conditions Fig. Unit Min. Max. G001 VCC Supply Voltage 0 7 V G002 V(C) Voltage at Outputs C1..5 0 VCC V G003 I(C) Current in Outputs C1..5 V(C)< 0V or V(C)> VCC -3 3 mA G004 I(TNRF) Current in TNRF -2 1 mA G005 I(TREF) Current in TREF -2 1 mA G006 I(ISET) Current in ISET -2...

iC-OV 5-BIT OPTO ENCODER Rev C0, Page 5/9 ELECTRICAL CHARACTERISTICS Operating Conditions: VCC= 5V ±10%, Tj= -25..125EC, unless otherwise noted Item Symbol Parameter Conditions Tj Fig. Unit EC Min. Typ. Max. Total Device 001 VCC Permissible Supply Voltage Range 4.5 5.5 V 002 I(VCC) Supply Current in VCC, Outputs C1..5 hi closed LED Control: R(ISET/AGND)= 14kS, I(LED). 10mA, NER= hi; I(C1..5)= 0, I(D1..5)= 80nA 7 13 mA 003 I(VCC) Supply Current in VCC, Outputs C1..5 lo closed LED Control: R(ISET/AGND)= 14kS, I(LED). 10mA, NER= hi; I(C1..5)= 0, I(D1..5)# 8nA 8 15 mA 004 fo Cut-off Frequency,...

iC-OV 5-BIT OPTO ENCODER Rev C0, Page 6/9 ELECTRICAL CHARACTERISTICS Operating Conditions: VCC= 5V ±10%, Tj= -25..125EC, unless otherwise noted Item Symbol Parameter Conditions Tj Fig. Unit EC Min. Typ. Max. Test Aid TNRF, TREF (continued) 403 It() Pull-Down Current (Test Aid Turn-on Threshold) V()= 0.5V -25 27 85 125 2 14 17 21 23 150 ìA ìA ìA ìA ìA 404 V()on Turn-on Voltage test aid active; I(TNRF)= 2..200ìA and I(TREF)= 100ìA, or I(TNRF)= 100ìA and I(TREF)= 2..200ìA -25 27 85 125 1.9 1.6 1.3 1.1 2.4 2.1 1.8 1.6 2.7 2.4 2.1 1.9 V V V V LED Current Control with Reference Photodiode DREF...

iC-OV 5-BIT OPTO ENCODER Rev C0, Page 7/9 Fig. 1: LED Current Control and Monitor DESCRIPTION OF FUNCTIONS LED Current Control The integrated LED current control with driver stage keeps the photoelectric current of the reference photodiode DREF constant. This compensates for ageing, dirt and the decline in LED efficiency as the temperature rises. The photoelectric current of the reference DREF and the dark current of compensation diode DDC are amplified in the current control. The amplified currents are subtracted from one another, yielding the actual value for the driver’s negative input...

iC-OV 5-BIT OPTO ENCODER Rev C0, Page 8/9 Fig. 2: Wiring the testing aid Tracks 1..5 The threshold IS of the current comparators for tracks C1 to C5 is determined by the resistor RSET and is about 0.5 x ISET. The threshold is supplemented by the amplified current of compensation diode DDC to compensate for the dark currents of photodiodes D1 to D5 and the amplifier input currents. The hysteresis of the current comparators enhances the interference immunity. Track 1 can be inverted by connecting pin NINV to ground (GND). If the pin remains open, the internal pull-up current source generates...

iC-OV 5-BIT OPTO ENCODER Rev C0, Page 9/9 This specification is for a newly developed product. iC-Haus therefore reserves the right to modify data without further notice. Please contact us to ascertain the current data. The data specified is intended solely for the purpose of product description and is not to be deemed guaranteed in a legal sense. Any claims for damage against us - regardless of the legal basis - are excluded unless we are guilty of premeditation or gross negligence. We do not assume any guarantee that the specified circuits or procedures are free of copyrights of third...