6661_nc0801ae

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: sales@npc.co.jp
NC0801AE
2010.03
SEIKO NPC CORPORATION —14