CIRRUS CS3302_07

CS3302
High-Z, Programmable Gain, Differential Amplifier
Features & Description
Description
z Signal
The CS3302 is a high-input-impedance, differential input, differential output amplifier with programmable gain,
optimized for amplifying signals from high-impedance
sensors such as hydrophones. The gain settings are binary weighted (x1, x2, x4, x8, x16, x32, x64) and are
selected using simple pin settings. Two sets of external
inputs, INA and INB, simplify system design as inputs
from a sensor and test DAC. An internal 800Ω termination can also be selected for noise tests.
Bandwidth: DC to 2 kHz
z Selectable Gain: x1, x2, x4, x8, x16, x32, x64
z Differential Inputs, Differential Outputs
•
•
•
•
Multiplexed inputs: INA, INB, 800Ω termination
Rough / fine charge outputs for CS5371/72
Max signal amplitude: 5 Vpp differential
Ultra-low input bias: < 1 pA
z Excellent Noise Performance
• 1 µVp-p between 0.1 Hz and 10 Hz
• 8.5 nV/ √Hz from 200 Hz to 2 kHz
Amplifier input impedance is very high, requiring less
than 1 pA of input current. Noise performance is very
good at 1 µVp-p between 0.1 Hz and 10 Hz, and a noise
density of 8.5 nV/ √Hz over the 200 Hz to 2 kHz bandwidth. Distortion performance is also extremely good,
typically -118 dB THD. Low input current, low noise, and
low total harmonic distortion make this amplifier ideal for
high-impedance differential sensors requiring maximum
dynamic range.
z Low Total Harmonic Distortion
• -118 dB THD typical (0.000126%)
• -112 dB THD maximum (0.000251%)
z Low Power Consumption
• Normal / LPWR / PWDN: 5 mA, 3.3 mA, 10 µA
z Single or Dual Power Supply Configurations
• VA+ = +5 V; VA- = 0 V; VD = +3.3 V to +5 V
• VA+ = +2.5 V; VA- = -2.5 V; VD = +3.3 V
VA+
INA+
INB+
ORDERING INFORMATION
See page 15.
GUARD
VD
640 Ω
500
+
OUTR+
OUTF+
400 Ω
500
640 Ω
GAIN0
GAIN1
GAIN2
400 Ω
MUX0
MUX1
500
640 Ω
INAINB-
640 Ω
500
+
VA-
http://www.cirrus.com
OUTFOUTR-
-
LPWR
PWDN
Copyright © Cirrus Logic, Inc. 2007
(All Rights Reserved)
DGND
DEC ‘07
DS596F3
CS3302
TABLE OF CONTENTS
1. CHARACTERISTICS AND SPECIFICATIONS........................................................................ 4
SPECIFIED OPERATING CONDITIONS ................................................................................ 4
ABSOLUTE MAXIMUM RATINGS .......................................................................................... 4
THERMAL CHARACTERISTICS ............................................................................................. 5
ANALOG CHARACTERISTICS ............................................................................................... 5
DIGITAL CHARACTERISTICS ................................................................................................ 8
POWER SUPPLY CHARACTERISTICS ................................................................................. 9
2. GENERAL DESCRIPTION..................................................................................................... 10
2.1. Analog Signals .............................................................................................................. 10
2.2.1.Analog Inputs ....................................................................................................... 10
2.3.2.Analog Outputs..................................................................................................... 10
2.4.3.Differential Signals ............................................................................................... 11
2.5.4.Guard Output........................................................................................................ 11
2.6. Digital Signals................................................................................................................ 11
2.7.1.Gain Selection ...................................................................................................... 11
2.8.2.Mux Selection ....................................................................................................... 11
2.9.3.Low Power Selection ............................................................................................ 11
2.10.4.Power Down Selection ....................................................................................... 11
2.11. Power Supplies ............................................................................................................. 11
2.12.1.Analog Power Supplies ...................................................................................... 11
2.13.2.Digital Power Supplies ....................................................................................... 12
2.14. Connection Diagram...................................................................................................... 13
3. PIN DESCRIPTION ................................................................................................................ 14
4. ORDERING INFORMATION ................................................................................................. 15
5. ENVIRONMENTAL, MANUFACTURING, & HANDLING INFORMATION............................ 15
6. PACKAGE DIMENSIONS ...................................................................................................... 16
2
DS596F3
CS3302
LIST OF FIGURES
Figure 1. CS3302 Noise Performance ............................................................................................ 5
Figure 2. Digital Input Rise and Fall Times ..................................................................................... 8
Figure 3. System Architecture....................................................................................................... 10
Figure 4. CS3302 Amplifier Connections ...................................................................................... 13
Figure 5. CS3302 Pin Assignments .............................................................................................. 14
LIST OF TABLES
Table 1. Digital Selection for Gain and Input Mux Control ............................................................. 8
Table 2. Pin Descriptions ............................................................................................................. 14
REVISION HISTORY
Revision
Date
Changes
PP2
JUL 2003
Final preliminary release.
F1
AUG 2005
Updated legal notice. Added MSL data.
F2
SEP 2005
Updated anti-alias resistor values, relative gain accuracy, input voltage noise,
and CS4373A part number.
F3
DEC 2007
Added watermark to indicate device is not recommended for new designs.
Contacting Cirrus Logic Support
For all product questions and inquiries contact a Cirrus Logic Sales Representative.
To find one nearest you go to www.cirrus.com
IMPORTANT NOTICE
Cirrus Logic, Inc. and its subsidiaries (“Cirrus”) believe that the information contained in this document is accurate and reliable. However, the information is subject
to change without notice and is provided “AS IS” without warranty of any kind (express or implied). Customers are advised to obtain the latest version of relevant
information to verify, before placing orders, that information being relied on is current and complete. All products are sold subject to the terms and conditions of sale
supplied at the time of order acknowledgment, including those pertaining to warranty, indemnification, and limitation of liability. No responsibility is assumed by Cirrus
for the use of this information, including use of this information as the basis for manufacture or sale of any items, or for infringement of patents or other rights of third
parties. This document is the property of Cirrus and by furnishing this information, Cirrus grants no license, express or implied under any patents, mask work rights,
copyrights, trademarks, trade secrets or other intellectual property rights. Cirrus owns the copyrights associated with the information contained herein and gives consent for copies to be made of the information only for use within your organization with respect to Cirrus integrated circuits or other products of Cirrus. This consent
does not extend to other copying such as copying for general distribution, advertising or promotional purposes, or for creating any work for resale.
CERTAIN APPLICATIONS USING SEMICONDUCTOR PRODUCTS MAY INVOLVE POTENTIAL RISKS OF DEATH, PERSONAL INJURY, OR SEVERE PROPERTY OR ENVIRONMENTAL DAMAGE (“CRITICAL APPLICATIONS”). CIRRUS PRODUCTS ARE NOT DESIGNED, AUTHORIZED OR WARRANTED FOR USE
IN PRODUCTS SURGICALLY IMPLANTED INTO THE BODY, AUTOMOTIVE SAFETY OR SECURITY DEVICES, LIFE SUPPORT PRODUCTS OR OTHER CRITICAL APPLICATIONS. INCLUSION OF CIRRUS PRODUCTS IN SUCH APPLICATIONS IS UNDERSTOOD TO BE FULLY AT THE CUSTOMER'S RISK AND CIRRUS DISCLAIMS AND MAKES NO WARRANTY, EXPRESS, STATUTORY OR IMPLIED, INCLUDING THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
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Cirrus Logic, Cirrus, and the Cirrus Logic logo designs are trademarks of Cirrus Logic, Inc. All other brand and product names in this document may be trademarks
or service marks of their respective owners.
DS596F3
3
CS3302
1.
CHARACTERISTICS AND SPECIFICATIONS
•
Min/Max characteristics and specifications are guaranteed over the Specified Operating Conditions.
•
Typical performance characteristics and specifications are derived from measurements taken at nominal supply voltages and TA = 25°C.
•
DGND = 0 V, all voltages with respect to 0 V.
SPECIFIED OPERATING CONDITIONS
Parameter
Symbol
Min
Nom
Max
Unit
Unipolar Power Supplies
Positive Analog
VA+
4.75
5.0
5.25
V
Negative Analog
(Note 1)
VA-
-0.25
0
0.25
V
Positive Digital
(Note 2)
VD
3.135
3.3
5.25
V
Bipolar Power Supplies
Positive Analog
VA+
2.375
2.5
2.625
V
Negative Analog
(Note 1)
VA-
-2.625
-2.5
-2.375
V
Positive Digital
(Note 2)
VD
3.135
3.3
3.465
V
Industrial (-IS, -ISZ)
TA
-40
-
85
°C
Thermal
Ambient Operating Temperature
Notes: 1. VA- must be the most negative voltage to avoid potential SCR latch-up conditions.
2. VD must conform to Digital Supply Differential under Absolute Maximum Ratings.
ABSOLUTE MAXIMUM RATINGS
CS3302
Parameter
DC Power Supplies
Positive Analog
Negative Analog
Digital
Symbol
Min
Max
Unit
VA+
VAVD
-0.3
-6.8
-0.3
6.8
0.3
6.8
V
V
V
Analog Supply Differential
[(VA+) - (VA-)]
VADIFF
-
6.8
V
Digital Supply Differential
[(VD) - (VA-)]
VDDIFF
-
6.8
V
Input Current, Any Pin Except Supplies
(Note 3)
IIN
-
+10
mA
Input Current, Power Supplies
(Note 3)
IIN
-
+50
mA
Output Current
(Note 3)
IOUT
-
+25
mA
PDN
-
500
mW
Analog Input Voltages
VINA
(VA-)-0.5
(VA+)+0.5
V
Digital Input Voltages
VIND
-0.5
(VD)+0.5
V
TA
-40
85
ºC
TSTG
-65
150
ºC
Power Dissipation
Ambient Operating Temperature (Power Applied)
Storage Temperature Range
WARNING: Operation at or beyond these limits may result in permanent damage to the device.
Normal operation is not guaranteed at these extremes.
Notes: 3. Transient currents up to 100mA will not cause SCR latch-up.
4
DS596F3
CS3302
THERMAL CHARACTERISTICS
CS3302
Parameter
Symbol
Allowable Junction Temperature
Min
Typ
Max
Unit
-
-
135
ºC
65
-
ºC / W
-
+85
ºC
Junction to Ambient Thermal Impedance
ΘJA
-
Ambient Operating Temperature (Power Applied)
TA
-40
ANALOG CHARACTERISTICS
CS3302
Parameter
Symbol
Min
Typ
Max
Unit
Noise Performance, Normal Power
Input Voltage Noise
f0 = 0.1 Hz to 10 Hz
VNPP
-
1
3
µVpp
Input Voltage Noise Density
f0 = 200 Hz to 2 kHz
VND
-
8.5
12
nV/ Hz
Input Current Noise Density
(Note 4)
IND
-
20
-
fA/ Hz
Noise Performance, Low Power (LPWR=1)
Input Voltage Noise
f0 = 0.1 Hz to 10 Hz
VNPP
-
1
3
µVpp
Input Voltage Noise Density
f0 = 200 Hz to 2 kHz
VND
-
10
15
nV/ Hz
Input Current Noise Density
(Note 4)
IND
-
1
-
fA/ Hz
Total Harmonic Distortion
(Note 5, 6)
THD
-
-118
-112
dB
Linearity
(Note 5, 6)
LIN
-
0.000126
0.000251
%
Distortion Performance, Normal Power
Distortion Performance, Low Power (LPWR=1)
Total Harmonic Distortion
(Note 5, 6)
THD
-
-118
-110
dB
Linearity
(Note 5, 6)
LIN
-
0.000126
0.000316
%
Notes: 4. Guaranteed by design and/or characterization.
5. Tested with a full scale input signal of 31.25 Hz.
6. Noise in the harmonic bins dominates THD and linearity measurements for x16, x32, and x64 gains.
CS3302 In-Band Noise
CS3302 Wide Band Noise
300
Noise Density (nV/rtHz)
Noise Density (nV/rtHz)
20
15
10
5
250
200
150
100
50
0
0
0
200 400
600
800 1000 1200 1400 1600 1800 2000
0.1
1
10
100
1000
10000 100000 1E+06
Frequency (Hz)
Frequency (Hz)
Figure 1. CS3302 Noise Performance
DS596F3
5
CS3302
ANALOG CHARACTERISTICS (CONT.)
CS3302
Parameter
Symbol
Min
Typ
Max
GAIN
x1
-
x64
Unit
Gain
Gain, Differential
Gain, Common Mode
(Note 7)
GAINCM
-
x1
-
Gain Accuracy, Absolute
(Note 8)
GAINABS
-
+1
+2
(Note 9)
GAINREL
-
+0.2
+0.5
%
(Note 4, 10)
GAINTC
-
5
-
ppm / ºC
OFST
-
+250
+750
µV
Gain Accuracy, Relative
Gain Drift
%
Offset
Offset Voltage, Input Referred
(Note 11)
Offset After Calibration, Absolute
(Note 12) OFSTCAL
-
+1
-
µV
(Note 13) OFSTRNG
(Note 4, 10) OFSTTC
-
100
-
% F.S.
-
1
-
µV / ºC
Offset Calibration Range
Offset Voltage Drift
Notes: 7. Common mode signals pass through the differential amplifier architecture.
8. Absolute gain accuracy tests the matching of x1 gain across multiple CS3302 devices.
9. Relative gain accuracy tests the tracking of x1,x2, x4,x16,x32,x64 gain relative to x8 gain on a single
CS3302 device.
10. Specification is for the parameter over the specified temperature range and is for the CS3302 device
only. It does not include the effects of external components.
11. Offset voltage is tested with the amplifier inputs connected to the internal 800Ω termination.
12. The absolute offset after calibration specification applies to the effective offset voltage of the CS3302
output when used with the CS5371/72 modulator and CS5376A digital filter, and is measured from the
digitally calibrated output codes of the CS5376A.
13. The CS3302 offset calibration is performed digitally with the CS5371/72 modulator and CS5376A digital
filter and includes the full scale signal range. Calibration offsets of greater than + 5% of full scale will
begin to subtract from system dynamic range.
6
DS596F3
CS3302
ANALOG CHARACTERISTIC (Cont.)
CS3302
Parameter
Symbol
Min
Typ
Max
Unit
BW
DC
VIN
(VA-)+0.7
(VA-)+0.7
-
2000
Hz
-
(VA+)-1.25
(VA+)-1.75
V
VINFS
-
-
5
2.5
1.25
625
312.5
156.25
78.125
Vp-p
Vp-p
Vp-p
mVp-p
mVp-p
mVp-p
mVp-p
Input Impedance, Differential
ZINDIFF
-
1, 20
-
TΩ, pF
Input Impedance, Common Mode
ZINCM
-
0.5, 40
-
TΩ, pF
Analog Input Characteristics
Input Signal Frequencies
Input Voltage Range (Signal + Vcm)
(Note 14)
Full Scale Input, Differential
x1
x2 - x64
x1
x2
x4
x8
x16
x32
x64
Input Bias Current
Crosstalk, Multiplexed Inputs
Common to Differential Mode Rejection
(Note 4)
(Note 4, 15)
IIN
-
1
40
pA
XT
-
-130
-
dB
CDMR
90
100
-
dB
Analog Output Characteristics
Full Scale Output, Differential
VOUT
-
-
5
Vpp
Output Voltage Range (Signal + Vcm)
VRNG
(VA-)+0.5
-
(VA+)-0.5
V
Output Impedance
(Note 16)
ZOUT
-
640
-
Ω
Output Impedance Drift
(Note 16)
ZTC
-
0.38
-
Ω/°C
IOUT
-
-
3.33
mA
CL
-
-
100
nF
Guard Output Voltage
VGUARD
-
Vcm
-
V
Guard Output Impedance
ZGOUT
-
500
-
Ω
Guard Output Current
IGOUT
-
40
-
µA
CGL
-
-
100
pF
Output Current
Load Capacitance
Guard Output Characteristics
Guard Load Capacitance
Notes: 14. No signal sources operating from external supplies should be applied to pins of the device prior to its
own supplies being established. Connecting any terminal to voltages greater than VA+ or less than VAmay cause destructive latch-up.
15. Ratio of common mode input amplitude vs. differential mode output amplitude for a perfectly matched
common mode input signal. Characterized with a 50 Hz, 500 mVpeak common mode sine wave applied
to the analog inputs.
16. Output impedance characteristics are primarily determined by the integrated anti-alias resistors. Values
are approximate and can vary +/- 10% depending on process parameters.
DS596F3
7
CS3302
DIGITAL CHARACTERISTICS
CS3302
Parameter
Symbol
Min
Typ
Max
Unit
Digital Characteristics
High-level Input Drive Voltage
(Note 17)
VIH
0.6*VD
-
VD
V
Low-level Input Drive Voltage
(Note 17)
VIL
0.0
-
0.8
V
IIN
-
+1
+10
µA
Input Leakage Current
Digital Input Capacitance
CIN
-
9
-
pF
Rise Times
tRISE
-
-
100
ns
Fall Times
tFALL
-
-
100
ns
Notes: 17. Device is intended to be driven with CMOS logic levels.
t rise
t fall
0.9 * VD
0.1 * VD
Figure 2. Digital Input Rise and Fall Times
Input Selection
MUX1
MUX0
Gain Selection
GAIN2
GAIN1
GAIN0
800 Ω termination
0
0
x1
0
0
0
INA only
1
0
x2
0
0
1
INB only
0
1
x4
0
1
0
INA + INB
1
1
x8
0
1
1
x16
1
0
0
x32
1
0
1
x64
1
1
0
Reserved
1
1
1
Table 1. Digital Selection for Gain and Input Mux Control
8
DS596F3
CS3302
POWER SUPPLY CHARACTERISTICS
CS3302
Parameter
Symbol
Min
Typ
Max
Unit
Power Supply Current, Normal Mode
Analog Power Supply Current
(Note 18)
IA
-
5.0
5.75
mA
Digital Power Supply Current
(Note 18)
ID
-
0.1
0.2
mA
Power Supply Current, Low Power Mode
Analog Power Supply Current, LPWR = 1
(Note 18)
IA
-
3.4
4.0
mA
Digital Power Supply Current, LPWR = 1
(Note 18)
ID
-
0.1
0.2
mA
Analog Power Supply Current, PWDN = 1
(Note 18)
IA
-
9
11
µA
Digital Power Supply Current, PWDN = 1
(Note 18)
ID
-
2
8
µA
PSRR
95
120
-
dB
Power Supply Current, Power Down Mode
Power Supply Rejection
Power Supply Rejection Ratio
(Note 4, 19)
Notes: 18. All outputs unloaded. Analog inputs connected to the internal 800 Ω termination. Digital inputs forced to
VD or DGND respectively.
19. Power supply rejection characterized with a 50 Hz, 400 mVpp sine wave applied separately to each
supply.
DS596F3
9
CS3302
2.
GENERAL DESCRIPTION
The CS3302 is a high-impedance, low-noise
CMOS differential input, differential output amplifier for precision analog signals between DC and
2 kHz. It has multiplexed inputs, rough/fine charge
outputs, and programmable gains of x1, x2, x4, x8,
x16, x32, and x64.
The amplifier’s performance makes it ideal for
low-frequency, high-dynamic-range applications
requiring low distortion and minimal power consumption. It’s optimized for use in acquisition systems designed around the CS5371/72 single/dual
∆Σ modulators and the CS5376A quad digital filter. Figure 3 shows the system-level architecture
of a 4-channel acquisition system using four
CS3302, two CS5372, one CS4373A, and one
CS5376A.
Geophone
or
Hydrophone
Sensor
Geophone
or
Hydrophone
Sensor
M
U
X
CS3301
CS3302
AMP
2.1
Analog Signals
2.1.1
Analog Inputs
The amplifier analog inputs are designed for highimpedance differential sensors. Input multiplexing
simplifies system connections by providing separate inputs for a sensor and test DAC (INA, INB) as
well as an internal termination for noise tests. The
MUX0, MUX1 digital pins determine which multiplexed input is connected to the amplifier.
2.1.2
Analog Outputs
The amplifier analog outputs are separated into
rough charge / fine charge signals to easily connect
to the CS5371/72 inputs. Each output also includes
a series resistor, requiring only two differential capacitors to create the CS5371/72 input anti-alias
filter.
CS5371
CS5372
System Telemetry
∆Σ
M odulator
M
U
X
CS3301
CS3302
AMP
CS5376A
µController
or
Configuration
EEPROM
Digital Filter
Geophone
or
Hydrophone
Sensor
Geophone
or
Hydrophone
Sensor
M
U
X
M
U
X
CS3301
CS3302
CS5371
CS5372
AMP
CS3301
CS3302
Communication
Interface
∆Σ
M odulator
AMP
CS4373A
Switch
Switch
MUX
MUX
Test
DAC
Figure 3. System Architecture
10
DS596F3
CS3302
2.1.3
Differential Signals
Analog signals into and out of the CS3302 are differential, consisting of two halves with equal but
opposite magnitude varying about a common mode
voltage.
A full scale 5 Vpp differential signal centered on a
-0.15 V common mode can have:
the signal common mode varies. The GUARD output will not drive a significant load, it only provides
a shielding voltage.
2.2
Digital Signals
2.2.1
Gain Selection
SIG- = -0.15 V - 1.25 V = -1.4 V
The CS3302 supports gain ranges of x1, x2, x4, x8,
x16, x32, and x64. They are selected using the
GAIN0, GAIN1, and GAIN2 pins as shown in
Table 1 on page 8.
SIG+ is +2.5 V relative to SIG-
2.2.2
SIG+ = -0.15 V + 1.25 V = 1.1 V
For the reverse case:
SIG+ = -0.15 V - 1.25 V = -1.4 V
SIG- = -0.15 V + 1.25 V = 1.1 V
SIG+ is -2.5 V relative to SIGThe total swing for SIG+ relative to SIG- is
(+2.5 V) - (-2.5 V) = 5 Vpp. A similar calculation
can be done for SIG- relative to SIG+. Note that a
5 Vpp differential signal centered on a -0.15 V
common mode voltage never exceeds 1.1 V and
never drops below -1.4 V on either half of the signal.
By definition, differential voltages are to be measured with respect to the opposite half, not relative
to ground. A multimeter differentially measuring
between SIG+ and SIG- in the above example
would properly read 1.767 Vrms, or 5 Vpp.
2.1.4
Guard Output
The GUARD pin outputs the common mode voltage of the currently selected analog signal input. It
can be used to drive the cable shield between a
high-impedance sensor and the amplifier inputs.
Driving the cable shield with the analog signal
common mode voltage minimizes leakage and improves signal integrity from high-impedance sensors.
The GUARD output is defined as the midpoint
voltage between the + and - halves of the currently
selected differential input signal, and will vary as
DS596F3
Mux Selection
The analog inputs to the amplifier are multiplexed,
with external signals applied to the INA+, INA- or
INB+, INB- pins. An internal termination is also
available for noise tests. Input mux selection is
made using the MUX0 and MUX1 pins as shown in
Table 1 on page 8.
Although a mux selection is provided to enable the
INA and INB switches simultaneously, significant
current should not be driven through them in this
mode. The CS3302 mux switches will maintain
good linearity only with minimal signal current.
2.2.3
Low Power Selection
For applications where power is critical, a lowpower mode can be selected. This mode reduces
amplifier power consumption at the expense of
slightly degraded performance. Low power mode
is selected using the LPWR pin, which is active
high.
2.2.4
Power Down Selection
A power-down mode is available to shut down the
amplifier when not in use. When enabled, all internal circuitry is disabled, the analog inputs and outputs go high-impedance, and the device enters a
micro-power state. Power down mode is selected
using the PWDN pin, which is active high.
2.3
2.3.1
Power Supplies
Analog Power Supplies
The analog power pins of the CS3302 are to be supplied with a total of 5 V between VA+ and VA-.
11
CS3302
This voltage is typically from a bipolar ±2.5 V supply. When using bipolar supplies the analog signal
common mode voltage should be biased to 0 V.
The analog power supplies are recommended to be
bypassed to system ground using 0.1 µF X7R type
capacitors.
the VA- supply before analog signals are applied to
the device. It is recommended to clamp the VAsupply to system ground using a reverse biased
Schottky diode to prevent possible latch-up conditions related to mismatched supply rail initialization.
The VA- supply is connected to the CMOS substrate and as such must remain the most negative
applied voltage to prevent potential latch-up conditions. Care should be taken to ensure analog input
voltages do not drop more than -0.3 V below the
VA- supply. Care should also be taken to establish
2.3.2
12
Digital Power Supplies
The digital power supply across the VD and DGND
pins is flexible and can be set to interface with
3.3 V or 5 V logic. The digital power supply should
be bypassed to system ground using a 0.01 µF X7R
type capacitor.
DS596F3
CS3302
2.4
Connection Diagram
Figure 4 shows a connection diagram for the
CS3302 amplifier when used with the CS5372 dual
∆Σ modulator, the CS4373A test DAC and the
CS5376A digital filter. The diagram shows differ-
ential sensors, a test DAC, and analog outputs with
anti-alias capacitors; power supply connections including recommended bypassing; and digital control connections back to the CS5376A GPIO pins.
G PIO (x3)
G PIO (x2)
G PIO
G PIO
3
2
G AIN
M UX
P W DN
To CS 5376 A
D igital C ontrol
LPW R
VA+
VD
VA+
V A+
VD
0.1µF
0.01µF
VD
CS3302
D ifferential
A m plifier
0.1µF
0.01µF
VA+
VA-
VA0.1µF
IN A +
VD
DG ND
IN A-
G UARD
IN B-
IN B+ O U TR -
O U TF-
O UTF+
M D A TA1
M FLAG 1
PW DN1
O U TR+
IN R+
IN F+
0.02µF
C 0G
0.02µF
C 0G
IN FIN R-
D ifferential
S ensor
M CLK
M S YNC
VRE F+
CS4373A
Test
D AC
CS 5372
∆Σ M odulator
2.5 V
R eference
VRE FD ifferential
S ensor
LP W R
O FST
IN RIN F0.02µF
C 0G
0.02µF
C 0G
IN F+
IN R+
IN A +
IN A-
G UARD
IN B-
IN B+ O U TR -
O U TF-
O UTF+
M D A TA2
M FLAG 2
PW DN2
O U TR+
VA+
VD
V A+
VD
VACS3302
D ifferential
A m plifier
0.1µF
0.01µF
VA-
VA0.1µF
0.1µF
DGND
G AIN
M UX
PW DN
2
3
D G ND
V A-
LPW R
G PIO
G PIO
G PIO (x2)
G PIO (x3)
To CS 5376 A
D igital C ontrol
Figure 4. CS3302 Amplifier Connections
DS596F3
13
CS3302
3.
PIN DESCRIPTION
Positive Analog Power Supply
VA+
1
24
MUX0
Input Mux Select
Negative Analog Rough Output
OUTR-
2
23
MUX1
Input Mux Select
Negative Analog Fine Output
OUTF-
3
22
GAIN0
Gain Range Select
Negative Analog Power Supply
VA-
4
21
GAIN1
Gain Range Select
Non-Inverting Input A
INA+
5
20
GAIN2
Gain Range Select
Inverting Input A
INA-
6
19
PWDN
Power Down Mode Enable
Inverting Input B
INB-
7
18
LPWR
Low Power Mode Enable
Non-Inverting Input B
INB+
8
17
TEST1
Test Mode Select
Test Mode Output
TESTOUT
9
16
VD
Positive Digital Power Supply
Positive Analog Fine Output
OUTF+
10
15
DGND
Digital Ground
Positive Analog Rough Output
OUTR+
11
14
TEST2
Test Mode Select
Test Mode Select
TEST0
12
13
GUARD
Guard Voltage Output
Figure 5. CS3302 Pin Assignments
Pin Name
VA+
Pin #
I/O
1
I
Pin Description
Positive analog supply voltage.
VA-
4
I
Negative analog supply voltage.
VD
16
I
Positive digital supply voltage.
DGND
15
I
Digital ground.
INA+, INA-
5, 6
I
Channel A differential analog inputs. Selected via MUX pins.
INB+, INB-
8, 7
I
Channel B differential analog inputs. Selected via MUX pins.
13
O
Guard voltage output.
OUTR+, OUTR-
11, 2
O
Rough charge differential analog outputs.
OUTF+, OUTF-
10, 3
O
Fine charge differential analog outputs.
GAIN0, GAIN1,
GAIN2
22, 21,
20
I
Gain range select. See Gain Selection table in Digital Characteristics section.
LPWR
18
I
Low power mode enable. Active high.
PWDN
19
I
Power down mode enable. Active high.
24, 23
I
Analog input select. See Input Selection table in Digital Characteristics section.
GUARD
MUX0, MUX1
TEST0
TEST1, TEST2
TESTOUT
12
I
17, 14
I
Test mode select, factory use only. Connect to VA- during normal operation.
Test mode select, factory use only. Connect to DGND during normal operation.
9
O
Test mode output, factory use only. Connect to VA- during normal operation.
Table 2. Pin Descriptions
14
DS596F3
CS3302
4.
ORDERING INFORMATION
Model
CS3302-IS
CS3302-ISZ (lead free)
5.
Temperature
Package
-40 to +85 °C
24-pin SSOP
ENVIRONMENTAL, MANUFACTURING, & HANDLING INFORMATION
Model Number
Peak Reflow Temp
MSL Rating*
Max Floor Life
CS3302-IS
240 °C
2
365 Days
CS3302-ISZ (lead free)
260 °C
3
7 Days
* MSL (Moisture Sensitivity Level) as specified by IPC/JEDEC J-STD-020.
DS596F3
15
CS3302
6.
PACKAGE DIMENSIONS
24 PIN SSOP PACKAGE DRAWING
N
D
E11
A2
E
b2
e
SIDE VIEW
A
A1
L
END VIEW
SEATING
PLANE
1 2 3
TOP VIEW
INCHES
DIM
A
A1
A2
b
D
E
E1
e
L
∝
MIN
-0.002
0.064
0.009
0.311
0.291
0.197
0.024
0.025
0°
MAX
0.084
0.010
0.074
0.015
0.335
0.323
0.220
0.027
0.040
8°
MILLIMETERS
MIN
MAX
-2.13
0.05
0.25
1.62
1.88
0.22
0.38
7.90
8.50
7.40
8.20
5.00
5.60
0.61
0.69
0.63
1.03
0°
8°
NOTE
2,3
1
1
Notes: 1. “D” and “E1” are reference datums and do not included mold flash or protrusions, but do include mold
mismatch and are measured at the parting line, mold flash or protrusions shall not exceed 0.20 mm per
side.
2. Dimension “b” does not include dambar protrusion/intrusion. Allowable dambar protrusion shall be
0.13 mm total in excess of “b” dimension at maximum material condition. Dambar intrusion shall not
reduce dimension “b” by more than 0.07 mm at least material condition.
3. These dimensions apply to the flat section of the lead between 0.10 and 0.25 mm from lead tips.
16
DS596F3