SM6661A Post-amplifier for Gyroscope OVERVIEW The SM6661A is a post-amplifier for use in combination with gyroscope ICs. The SM6661A has a built-in 2system post-amplifier, so that it can amplify two output signals of gyroscope IC with a single SM6661A. It features a simple method to change the different image stabilizing gain and frequency characteristics depending on the models. It also has a built-in sleep function making it easy to connect the output signal of gyroscope IC to A/D converter. ■ ■ ■ ■ ■ ■ ■ (Top view) VCC SLEEP VSIG_OUT1 GAIN1 APPLICATIONS DVC DSC Device Package SM6661AB 16-pin QFN PACKAGE DIMENSIONS (Unit: mm) Weight: 9mg Top view Bottom view 2.50 ± 0.05 1.30 ± 0.05 1.30 ± 0.05 ORDERING INFORMATION 16 0.60 max ■ 2.50 ± 0.05 ■ VSIG_IN2 VREF_IN2 VCC/2 GND 1 0.05 0.40 ■ Supply voltage range: 3.0 to 3.6V Operating ambient temperature range: −20 to +80°C 2-system input and output (reverse phase output) Corresponds to 2-axis of gyroscope output Adjustable output gain and frequency characteristics by external components Output gain: 30 to 50dB (variable amplification control) Zero-rate voltage compensation function for simple interface to A/D converter connected to subsequent stage Sleep function built-in Small package: 16-pin QFN VSIG_OUT2 GAIN2 HPF2 GND ■ PINOUT HPF1 VCC VREF_IN1 VSIG_IN1 FEATURES 0.40 ± 0.05 0.325 ± 0.05 16 1 C0.05 0.18 ± 0.05 0.08 ± 0.05 0.05 M 0.40 SEIKO NPC CORPORATION —1 SM6661A BLOCK DIAGRAM VCC HPF1 GAIN1 − VREF_IN1 + VSIG_IN1 − AMP 30dB AMP 0 to 20dB VSIG_OUT1 + GND SLEEP VCC/2 VCC REF − VREF_IN2 + VSIG_IN2 + AMP 30dB AMP 0 to 20dB VSIG_OUT2 − HPF2 GAIN2 GND PIN DESCRIPTION Number Name I/O*1 Type*2 1 HPF1 O A 30dB amplifier output pin 1 2 VCC – – Supply pin 3 VREF_IN1 I A Gyroscope IC reference voltage input pin 1 4 VSIG_IN1 I A Gyroscope IC signal input pin 1 5 GND – – Ground pin 6 VCC/2 O A Reference voltage pin Note. Connect smoothing capacitors. 7 VREF_IN2 I A Gyroscope IC reference voltage input pin 2 8 VSIG_IN2 I A Gyroscope IC signal input pin 2 9 GND – – Ground pin 10 HPF2 O A 30dB amplifier output pin 2 11 GAIN2 I A Variable gain amplifier input pin 2 12 VSIG_OUT2 O A Signal output pin 2 13 VCC – – Supply pin 14 SLEEP Ip D Sleep mode control pin with built-in pull-up resistor HIGH: sleep mode, LOW: normal operation 15 VSIG_OUT1 O A Signal output pin 1 16 GAIN1 I A Variable gain amplifier input pin 1 Description *1. I: input, Ip: input with built-in pull-up resistor, O: output *2. A: analog, D: digital SEIKO NPC CORPORATION —2 SM6661A PIN EQUIVALENT CIRCUITS Number Name I/O*1 Equivalent circuit 5.6kΩ VSIG_IN1 VSIG_IN2 3 4 7 8 VREF_IN1 VSIG_IN1 VREF_IN2 VSIG_IN2 1kΩ I VREF_IN1 VREF_IN2 1 10 HPF1 HPF2 O 12 15 VSIG_OUT2 VSIG_OUT1 O 11 16 GAIN2 GAIN1 I 1kΩ 5.6kΩ HPF1 HPF2 VSIG_OUT1 VSIG_OUT2 GAIN1 GAIN2 500Ω SEIKO NPC CORPORATION —3 SM6661A Number Name I/O*1 6 VCC/2 O Equivalent circuit VCC/2 100kΩ 14 SLEEP Ip SLEEP 200Ω *1. I: input, Ip: input with built-in pull-up resistor, O: output Note. Resistance values indicate design values. SEIKO NPC CORPORATION —4 SM6661A SPECIFICATIONS Absolute Maximum Ratings GND = 0V Parameter Pin Symbol Rating Unit Supply voltage VCC VCC 5.0 V Input voltage VREF_IN1, VREF_IN2, VSIG_IN1, VSIG_IN2, HPF1, HPF2, GAIN1, GAIN2, SLEEP VIN VCC + 0.3 to GND – 0.3 V TSTG − 40 to +125 °C PD 0.7 W TJMAX +125 °C Storage temperature range Power dissipation*1 Junction temperature *1. When mounted on a NPC’s standard board (76.2mm × 114.3mm, 1.6mm thickness, FR-4 glass-epoxy board). Thermal resistance θja = 64°C/W Recommended Operating Conditions GND = 0V Rating Parameter Pin Supply voltage VCC SLEEP pin applied voltage SLEEP Operating ambient temperature Reference input voltage VREF_IN1, VREF_IN2, VSIG_IN1, VSIG_IN2 Signal input amplitude*1 VSIG_IN1, VSIG_IN2 Output gain variable range VSIG_OUT1, VSIG_OUT2 Variable gain amplifier feedback resistance Output load resistance VSIG_OUT1, VSIG_OUT2 Symbol Unit min typ max VCC 3.0 3.3 3.6 V VSLEEP 0 – VCC V Ta –20 25 80 °C VREF_IN 1.25 1.35 2.10 V VSIG_IN_AC – – 47 mVpp GRANGE 30 – 50 dB R2 27 – 330 kΩ RL 50 – – kΩ *1. When VCC = 3.0V, 30dB output gain setting SEIKO NPC CORPORATION —5 SM6661A Electrical Characteristics DC Characteristics VCC = 3.3V, GND = 0V, Ta = 25°C, circuit constant is same as “TYPICAL APPLICATION CIRCUIT”, unless otherwise noted. Rating Parameter Symbol Current consumption 1 ICC1 Condition Unit min typ max SLEEP = LOW, VCC = 3.3V − 5.5 7.5 mA SLEEP = LOW, VCC = 3.6V – 7.0 9.0 mA Current consumption 2 ICC2 SLEEP = HIGH (sleep mode) − – 1.0 µA High-level input voltage VIH 2.0 – – V Low-level input voltage VIL SLEEP pin, VCC = 3.0 to 3.6V, Ta = –20 to +80°C – – 0.8 V High-level input leakage current*1 ILH SLEEP pin, 3.3V input voltage – – ± 1.0 µA Low-level input current*1 ILL SLEEP pin, 0.0V input voltage −38 −33 −28 µA Input current (SLEEP = HIGH)*1 ILEAK VSIG_IN1, VSIG_IN2, VREF_IN1, VREF_IN2 pins – – ± 0.1 mA Input current (SLEEP = LOW)*1 IIN VSIG_IN1, VSIG_IN2, VREF_IN1, VREF_IN2 pins, 1.35V input voltage –0.2 –0.045 +0 mA VCC–0.3 VCC–0.1 – V – 0.1 0.3 V – ±5 ± 20 mV VCC/2–0.1 VCC/2 VCC/2+0.1 V High-level output voltage VOH Low-level output voltage VOL Offset voltage*2 VOFFSET VCC/2 pin voltage VVCC/2 VSIG_OUT1, VSIG_OUT2 pins, RL = 100kΩ VSIG_OUT1, VSIG_OUT2 pins, potential difference from VCC/2 pin, R1 = 150kΩ, R2 = 330kΩ VCC/2 pin *1. Sink current is defined as positive value. *2. R1 and R2 indicate the values of input resistor and feedback resistor for variable gain amplifier respectively. Refer to “TYPICAL APPLICATION CIRCUIT”. AC Characteristics VCC = 3.3V, GND = 0V, Ta = 25°C, circuit constant is same as “TYPICAL APPLICATION CIRCUIT”, unless otherwise noted. Rating Parameter Symbol Condition Unit min typ max 29 30 31 dB 35.7 36.8 37.9 dB 30dB amplifier output gain Gain1 HPF1, HPF2 pins *1 Gain2 VSIG_OUT1, VSIG_OUT2 pins, VNOISE At 1Hz – 0.05 – µVrms/√Hz Output gain Input referred voltage noise*2 Lower cutoff frequency *1*3 fCL R1 = 150kΩ, C1 = 22µF – 0.05 – Hz *1*4 fCH R2 = 330kΩ, C2 = 2200pF – 219 – Hz Upper cutoff frequency *1. As for these parameters, the characteristics are determined by external components, and the specifications are guaranteed by design and characteristics evaluation. The rating values are shown without considering variability of external components. *2. Input referred voltage noise is a design value when short-circuiting between VSIG_IN1 and VREF_IN1 pins, VSIG_IN2 and VREF_IN2 pins, without inputting external signal. *3. R1 and C1 indicate the values of input resistor and input capacitor for variable gain amplifier respectively. Refer to “TYPICAL APPLICATION CIRCUIT”. *4. R2 and C2 indicate the values of feedback resistor and feedback capacitor for variable gain amplifier respectively. Refer to “TYPICAL APPLICATION CIRCUIT”. SEIKO NPC CORPORATION —6 SM6661A FUNCTIONAL DESCRIPTION Sensor Signal Input and Output The signal output of gyroscope IC is connected to VSIG_IN1 pin. The first stage amplifier of SM6661A is differential input, so that VREF_IN1 pin is input zero-rate voltage of gyroscope IC. (Normally, the reference voltage output pin of gyroscope IC should be connected to VREF_IN1 pin.) The amplified signal is output from VSIG_OUT1 pin. Note that the output signal is reverse phase of input signal from VSIG_IN1 pin. The zero-rate voltage of output signal is VCC/2V. The description of VSIG_IN2, VREF_IN2 and VSIG_OUT2 pins are the same as above VSIG_IN1, VREF_IN1 and VSIG_OUT1 pins. VCC/2 Pin The VCC/2 pin is a reference voltage pin. Smoothing capacitors should be connected between VCC/2 pin and GND. The recommended values of smoothing capacitors are parallel-connected 10µF electrolytic capacitor and 0.1µF ceramic capacitor. Output Gain and Frequency Characteristics Setting The output gain and frequency characteristics of SM6661A are adjustable with connecting external resistors and capacitors as shown below. C2 C1 R1 R2 HPF1 HPF2 − + GAIN1 GAIN2 AMP 30dB VSIG_OUT1 VSIG_OUT2 − AMP 0 to 20dB + Output gain setting The output gain of SM6661A is adjustable by changing the value of external resistors R1 and R2. The SM6661A has a built-in 30dB amplifier, so that the output gain “Gain2” is determined by the formula below; Gain2 = 20 × log ( R2 ) + 30 [dB] R1 SEIKO NPC CORPORATION —7 SM6661A Frequency characteristics setting The frequency characteristics of SM6661A is adjustable by changing the value of external capacitors C1 and C2. The lower cutoff frequency “fCL” and upper cutoff frequency “fCH” are determined by the formula below; (These values should be set to meet the condition “fCL < fCH”, in order to construct the band-pass filter.) fCL = 1 [Hz] (2π × R1 × C1) fCH = 1 [Hz] (2π × R2 × C2) External components setting The values of R1 and C1 should be set considering the time constant (τ) that is determined by the formula below; τ = R1 × C1 [s] The R2 resistor value is determined by R1 resistor value and output gain setting. Note that the offset voltage increases as the R2 value increases. The R2 recommended value is 27kΩ to 330kΩ. Sleep Mode Function The SM6661A has the sleep mode function. When SLEEP pin set to “High”, the SM6661A operation becomes sleep mode. In sleep mode operation, the current consumption becomes up to 1.0µA and VSIG_OUT1 and VSIG_OUT2 pins are setting high-impedance. Control pin SM6661A operation SLEEP LOW Normal operation HIGH Sleep mode SEIKO NPC CORPORATION —8 SM6661A TYPICAL APPLICATION CIRCUIT C1 R1 22µF 150kΩ + 22µF 0.1µF VCC HPF1 GAIN1 C2 2200pF R2 330kΩ Sensor 1 A/D converter 1 Reference voltage VREF_IN1 − VREF_IN Sensor signal VSIG_IN1 + VREF_IN Amplified signal − AMP 30dB VCC/2 AMP VSIG_OUT1 + GND SLEEP VCC/2 0.1µF VCC REF Sensor 2 Reference voltage 0.1µF VREF_IN2 − VREF_IN Sensor signal VSIG_IN2 + VREF_IN + AMP 30dB GND − HPF2 Amplified signal C1 R1 22µF 150kΩ 36.8dB fCL 0.05Hz fCH 219Hz VSIG_OUT2 AMP GAIN2 Total gain 22µF A/D converter 2 + + 10µF VCC/2 R2 330kΩ C2 2200pF SEIKO NPC CORPORATION —9 SM6661A TYPICAL PERFORMANCES 8 8 6 6 ICC1 [mA] ICC1 [mA] VCC = 3.3V, GND = 0V, Ta = 25°C, circuit constant is same as “TYPICAL APPLICATION CIRCUIT”, unless otherwise noted. 4 2 4 2 0 2.7 3.0 3.3 3.6 3.9 VCC [V] 0 −40 −20 0 20 40 60 80 100 Ta [°C] Figure 1. Current consumption 1 vs. Supply voltage Figure 2. Current consumption 1 vs. Ambient temperature 0 IIN [µA] −20 −40 −60 −80 −100 2.7 VSIG_IN1/ VSIG_IN2 VREF_IN1/ VREF_IN2 3.0 3.3 3.6 3.9 VCC [V] Figure 3. Input current vs. Supply voltage SEIKO NPC CORPORATION —10 SM6661A 40 39.0 Gain2 [dB] Gain2 [dB] 38.0 35 30 37.0 36.0 25 0.01 0.1 1 10 100 1000 35.0 −40 −20 0 20 40 60 80 100 Ta [°C] Frequency [Hz] Figure 4. Output gain vs. Frequency Figure 5. Output gain vs. Ambient temperature (at 10Hz input frequency) 60 [A] Gain2 [dB] 50 40 [B] [C] 30 20 0.01 0.1 1 10 100 Frequency [Hz] Figure 6. Output gain vs. Frequency (when changing output gain setting*1) *1. Each setting is measured without connecting feedback capacitor C2 for variable gain amplifier, high-frequency bandwidth is not limited. Output gain setting of each characteristics are shown below; [A]: 50.0 dB setting (R1 = 33kΩ, R2 = 330kΩ) [B]: 36.8 dB setting (R1 = 150kΩ, R2 = 330kΩ) [C]: 30.0 dB setting (R1 = 330kΩ, R2 = 330kΩ) SEIKO NPC CORPORATION —11 SM6661A 1000 VOUT [µVrms/√Hz] VOUT [V] 1.655 ∆VOUT 1.650 ∆IS 100 10 1 Output impedance ∆VOUT/∆IS = 3Ω 1.645 0 100 200 300 400 500 IS [µA] 0.1 0.01 0.1 1 10 100 1000 Frequency [Hz] Figure 7. Output current vs. Output voltage*1 (VSIG_OUT1, VSIG_OUT2 pins) Figure 8. Output noise vs. Frequency*2 −60 Crosstalk [dB] −70 −80 −90 −100 −110 −120 1 10 100 1000 Frequency [Hz] Figure 9. Crosstalk vs. Frequency*3 *1. IS indicates the source current of VSIG_OUT1 or VSIG_OUT2 pins. *2. When short-circuiting between VSIG_IN1 and VREF_IN1 pins, VSIG_IN2 and VREF_IN2 pins, without inputting external signal. Measurement equipment: Agilent 35670A FFT Dynamic Signal Analyzer, in “FFT ANALYSIS” mode Input referred voltage noise at 1Hz frequency: 0.05µVrms/√Hz (calculated based on 35µVrms/√Hz output noise at 1Hz frequency and 36.8 dB output gain “Gain2”) *3. When measured without connecting feedback capacitor C2 for variable gain amplifier, high-frequency bandwidth is not limited. SEIKO NPC CORPORATION —12 SM6661A RECOMMENDED FOOTPRINT PATTERN (Unit: mm) 2.90 0.60 0.18 1.30 2.90 0.40 1.30 0.60 SEIKO NPC CORPORATION —13 SM6661A 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 massproduction 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 form 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] NC0801AE 2010.03 SEIKO NPC CORPORATION —14