SM3471AB Interpolation Encoder IC OVERVIEW The SM3471 is an interpolation IC for encoders. It accepts displacement detection, 2-phase analog signals (A and B phases) and a zero point detection analog signal (Z phase) from an encoder, interpolates the signals by a specified interpolation factor, and outputs corresponding 2-phase digital signals (A and B phases) and a zero point detection digital signal (Z phase). FEATURES ▪ Interpolation switching function: ×2, 4, 8, 16 (selectable) ▪ Input frequency: 300kHz (max) ▪ Output frequency: 2.5MHz (max) ▪ Supply voltage: 2.7 to 5.5V ▪ Operating temperature range: –40 to +125°C ▪ Package: QFN24 (size: 4mm × 4mm) ORDERING INFORMATION Device Package SM3471AB-G*1 24 pin QFN *1. “-G” option code lead-free package 0.2 S B PACKAGE DIMENSIONS 4.00±0.1 0.2 S A 0.75 0.75 A C0.11 0.50 2.40 ±0.1 0.45±0.1 0.65 MAX 0.05 MAX 0 MIN 0.22±0.05 // 0.2 S 3 .0 0.15 2.40 ±0.1 C0 4.00±0.1 B 0.50 0.22±0.05 0.05 M S AB S 0.08 S [unit:mm] SEIKO NPC CORPORATION - 1 SM3471AB PINOUT QFN24 package (Top view) 24 23 22 21 20 19 VSS 1 18 VREF NC 2 17 NC VDD 3 16 NC 25 25TP DA 4 DB 5 14 SEL0 DZ 6 13 ZSEL 7 8 9 10 15 SEL1 11 12 PIN DESCRIPTION Pin No. Name I/O*1 1 VSS - Ground 2 NC - No connection 3 VDD - Power supply 4 DA O Displacement detector signal output (A) 5 DB O Displacement detector signal output (B) 6 DZ O Zero point detector signal output (Z) 7 NC - No connection 8 NC - No connection 9 NC - No connection 10 VSS - Ground 11 VSS - Ground 12 NC - No connection 13 ZSEL I Z-phase output timing setting input with pull-down resistor 14 SEL0 I Interpolation setting input with pull-down resistor 15 SEL1 I Interpolation setting input with pull-down resistor 16 NC - No connection 17 NC - No connection 18 VREF O VDD/2 level voltage output 19 ZN I Zero point detector inverse-phase signal input 20 Z I Zero point detector signal input 21 AN I Displacement detector signal (–cos) input 22 A I Displacement detector signal (cos) input 23 BN I Displacement detector signal (–sin) input 24 B I Displacement detector signal (sin) input 25 TP - Thermal pad. Connect to VSS or leave OPEN. Description *1. I: Input pin O: Output pin I/O: Input/Output pin VSS terminals number 1, 10 and 11 must be connected to the ground on the mounting board. SEIKO NPC CORPORATION - 2 SM3471AB BLOCK DIAGRAM VDD A AN B AMP BN Interpolation Buffer DA Buffer DB Buffer DZ Z ZN SEL0 SEL1 ZSEL Vref VREF VSS SPECIFICATIONS Absolute Maximum Ratings VSS=0V Parameter *1 Supply voltage 1 *1,*4 Input voltage Symbol Condition Rating Unit VDD VDD pin –0.3 to +6.5 V VIN *1,*4 Output voltage *2 VOUT Output current IOUT Junction temperature*3 Tj *1 Power dissipation *5 Storage temperature PD Tstg1 *6 Input pins –0.3 to VDD+0.3 V *7 –0.3 to VDD+0.3 V *7 -1.8 to 1.8 mA +150 °C 1570 mW –40 to +125 °C Output pins Output pins *8 Ta=25°C *1. Parameters must not exceed the ratings, not even momentarily. If the rating is exceeded, there is a risk of IC failure, deterioration in characteristics, and decrease in reliability. *2. Parameter must not exceed the rating on average. If the rating is exceeded, there is a risk of IC failure, deterioration in characteristics and decrease in reliability. *3. Parameter should not exceed the rating. If the rating is exceeded, there is a risk of deterioration in characteristics and decrease in reliability. *4. VDD value is the recommended operating voltage rating. *5. Stored separately without packing material in Nitrogen or vacuum atmosphere. *6. SEL0, SEL1, ZSEL, A, AN, B, BN, Z, and ZN terminals. *7. DA, DB, and DZ terminals. *8. 114.3×76.2×1.6mm, 150% wiring ratio, FR-4 4-layer board (with thermal pad connections). Dissipation will vary due to differences in board specifications and footprint pattern. SEIKO NPC CORPORATION - 3 SM3471AB Power Dissipation 2000 Power dissipation Pd [mW] 1800 1600 1400 1200 1000 800 600 400 200 0 0 25 50 75 100 125 Operating temperature Ta [°C] Recommended Operating Conditions The recommended operating conditions are the conditions for which the electrical characteristics are guaranteed. VSS=0V Parameter Symbol Supply voltage Logic input voltage *1 Analog Input voltage range *1 Input signal amplitude Condition MIN TYP MAX Unit VDD VDD pin 2.7 - 5.5 V VIN1 SEL0, SEL1, ZSEL pins VSS - VDD V VIN2 A, AN, B, BN, Z, and ZN pins 1 - VDD–1 V A, AN, B, BN, Z, and ZN pins 0.6 - - Vpp A-AN center offset B-BN center offset VDD=5.0V, 25°C -25 - 25 mV VINPP Input offset voltage*2 VOFFSET Input signal frequency FIN Operating temperature range Ta A, AN, B, BN, Z, and ZN pins - - 300 kHz –40 - +125 °C Note. Operation outside the recommended operating conditions may adversely affect reliability. Use only within specified ratings. *1 Definition VIN2 and VINPP *2 Definition VOFFSET A, AN(B, BN) each ±12.5mV ⇒Absolute value:25mV VDD VIN2(max)=VDD-1V A(B) VIN2 VINPP VIN2(min)=1 AMP AN(BN) 0V * Higher accuracy is obtained by increasing signal amplitude VINPP, so largest value within the input voltage range is recommended. SEIKO NPC CORPORATION - 4 SM3471AB Electrical Characteristics VDD=2.7 to 5.5V, VSS=0V, Ta=–40 to +125°C unless otherwise noted Parameter Symbol *1 Current consumption Logic input voltage*2 Logic input current*2 Output voltage*3 Output frequency IDD Condition No load MIN TYP MAX Unit mA - 15 25 VIH 0.7VDD - VDD VIL VSS - 0.3VDD IIH VIN=VDD, Ta=25°C 20 - 200 IIL VIN=VSS, Ta=25°C –1 - - V μA VoutH Iout = +1.5mA VDD–0.4 - - VoutL Iout = –1.5mA - - 0.3 - - 2.5 MHz VDD=5.0V, 16x interpolation, Input ideal sin(cos) wave, 10kHz input frequency, 3.0Vppinput amplitude - - 6 Degrees 0.1VDD to 0.9VDD, CL=20pF - - 10 ns fout *4 Angular error (max – min) ARAL Rise/Fall time trf V *1. Typical conditions: VDD=5V, Ta=25°C, 8x interpolation, FIN=10kHz *2. SEL0, SEL1, and ZSEL terminals. *3. DA, DB, and DZ terminals. *4. The angular error expresses the variation from the ideal phase difference of interpolation outputs DA and DB as a phase difference of the input period. Converting 6° and expressing as a percentage of the output period gives 26.6% using equation (1) below. 6 deg× 16 x = 26.6% 360 deg (1) (where 16x is the interpolation factor) TPIN : input period A(cos) B(sin) TPOUT : output period DA 16x multiplier DB TPOUT : output period Conversion to output period reference TPOUT = TPIN / Multiplier = 360deg DA ARAL_OUT = 6deg × 16 = 96deg DB = ARAL_OUT 6deg × 16 360deg = 26.6% SEIKO NPC CORPORATION - 5 SM3471AB FUNCTIONAL DESCRIPTION Interpolation Circuit The interpolation circuit passes the input signals, through a resistance network divider, converts the signals to binary using comparators, and outputs 2-phase digital signals corresponding to the interpolation factor selected by register data using logical operation processing. The interpolation factor is set using input level of SEL0 and SEL1 terminals. SEL1 SEL0 Interpolation factor L L 2 L H 4 H L 8 H H 16 ANsig(-cos) Buffer DA Buffer DB Buffer DZ Asig(cos) BNsig(-sin) Resistor Ladder Comparator Logic Bsig(sin) Zsig Comparator SEL0, SEL1 Output Reference voltage VREF terminal outputs the VDD/2 voltage as a reference voltage to use in single-ended input. SEIKO NPC CORPORATION - 6 SM3471AB Timing Diagrams Interpolation Function and Z-phase Input/Output Timing DZ signal timing is settable by ZSEL terminal. interpolation x2 ＣＷ interpolation x2ＣＣＷ T B_INPUT (Sin) A_INPUT (Cos) Z_INPUT A_INPUT (Cos) Max Max Z_INPUT DA DA DB DB DZ ZSEL=1 DZ ZSEL=1 DZ ZSEL=0 DZ ZSEL=0 interpolation x4 ＣＷ A_INPUT (Cos) Max Max Z_INPUT DA DA DB DB DZ ZSEL=1 DZ ZSEL=1 DZ ZSEL=0 DZ ZSEL=0 interpolation x8 ＣＷ Max Max interpolation x8 ＣＣＷ T B_INPUT (Sin) T B_INPUT (Sin) A_INPUT (Cos) A_INPUT (Cos) Max Max Z_INPUT DA DA DB DB DZ ZSEL=1 DZ ZSEL=1 DZ ZSEL=0 DZ ZSEL=0 interpolation x16 ＣＷ Max Max interpolation x16 ＣＣＷ T B_INPUT (Sin) T B_INPUT (Sin) A_INPUT (Cos) Z_INPUT Max T B_INPUT (Sin) A_INPUT (Cos) Z_INPUT Max interpolation x4 ＣＣＷ T B_INPUT (Sin) Z_INPUT T B_INPUT (Sin) A_INPUT (Cos) Max Max Z_INPUT DA DA DB DB DZ ZSEL=1 DZ ZSEL=1 DZ ZSEL=0 DZ ZSEL=0 Max Max SEIKO NPC CORPORATION - 7 SM3471AB TYPICAL APPLICATION CIRCUITS Typical Application Circuit 1 A/B/Z-phase differential input 5V 1uF 0.01uF VDD DA A(cos) DB A AN(-cos) AN SM3471 B(sin) DZ B BN(-sin) BN Z SEL0 SEL1 Interpolation setting ZSEL DZ output timing setting Z ZN ZN VREF VSS VSS VSS Typical Application Circuit 2 A/B/Z-phase single-ended input (offset voltage=VDD/2) 5V 1uF 0.01uF VDD DA A(cos) DB A AN B(sin) SM3471 BN Z DZ B SEL0 SEL1 Interpolation setting ZSEL DZ output timing setting Z ZN VDD/2 =2.5V VREF VSS VSS VSS 0.01uF SEIKO NPC CORPORATION - 8 SM3471AB Please pay your attention to the following points at time of using the products shown in this document. 1. The products shown in this document (hereinafter ”Products”) are designed and manufactured to the generally accepted standards of reliability as expected for use in general electronic and electrical equipment, such as personal equipment, machine tools and measurement equipment. The Products are not designed and manufactured to be used in any other special equipment requiring extremely high level of reliability and safety, such as aerospace equipment, nuclear power control equipment, medical equipment, transportation equipment, disaster prevention equipment, security equipment. The Products are not designed and manufactured to be used for the apparatus that exerts harmful influence on the human lives due to the defects, failure or malfunction of the Products. If you wish to use the Products in that apparatus, please contact our sales section in advance. In the event that the Products are used in such apparatus without our prior approval, we assume no responsibility whatsoever for any damages resulting from the use of that apparatus. 2. NPC reserves the right to change the specifications of the Products in order to improve the characteristics or reliability thereof. 3. The information described in this document is presented only as a guide for using the Products. No responsibility is assumed by us for any infringements of patents or other rights of the third parties which may result from its use. No license is granted by implication or otherwise under any patents or other rights of the third parties. Then, we assume no responsibility whatsoever for any damages resulting from that infringements. 4. The constant of each circuit shown in this document is described as an example, and it is not guaranteed about its value of the mass production products. 5. In the case of that the Products in this document falls under the foreign exchange and foreign trade control law or other applicable laws and regulations, approval of the export to be based on those laws and regulations are necessary. Customers are requested appropriately take steps to obtain required permissions or approvals from appropriate government agencies. SEIKO NPC CORPORATION 1-9-9, Hatchobori, Chuo-ku, Tokyo 104-0032, Japan Telephone: +81-3-5541-6501 Facsimile: +81-3-5541-6510 http://www.npc.co.jp/ Email:[email protected] ND15011-E-00 2015.08 SEIKO NPC CORPORATION - 9