SEMTECH SX9300EVK

SX9300
Ultra Low Power, Dual Channel
Smart Proximity SAR Compliant Solution
WIRELESS & SENSING PRODUCTS
Datasheet
GENERAL DESCRIPTION
KEY PRODUCT FEATURES
The SX9300 is the world’s first dual channel capacitive
Specific Absorption Rate (SAR) controller that accurately
discriminates between an inanimate object and human
body proximity. The resulting detection is used in portable
electronic devices to reduce and control radio-frequency
(RF) emission power in the presence of a human body,
enabling
significant
performance
advantages
for
manufacturers of electronic devices with EMF radiation
sources to meet stringent emission regulations' criteria and
Specific Absorption Rate (SAR) standards. Operating
directly from an input supply voltage of 2.7 to 5.5V, the
SX9300 outputs its data via a 1.65 – 5.5V host compatible
I2C serial bus.
The I2C serial communication bus port is compatible with
1.8V host control to report body detection/proximity and to
facilitate parameter settings adjustment. Upon proximity
detection, the NIRQ output asserts, enabling the user to
either determine the relative proximity distance, or simply
obtain an indication of detection. The serial bus can also
serve to overwrite detection thresholds and operational
settings in the event the user wants to change them from
their factory presets.
The SX9300 includes an on-chip auto-calibration controller
that regularly performs sensitivity adjustments to maintain
peak performance over a wide variation of temperature,
humidity and noise environments, providing simplified
product development and enhanced performance. A
dedicated transmit enable (TXEN) pin is available to
synchronize proximity measurements to RF transmission,
enabling very low supply current and high noise immunity
by only measuring proximity when requested.
2.7 – 5.5V Input Supply Voltage
Dual SAR Capacitive Sensor Inputs
On-Chip SAR Engine For Body versus Inanimate Object
Detection
Stable Proximity Sensing With Temperature
20mm detection distance
Capacitance Offset Compensation to 30pF
Active Sensor Guarding
Automatic Calibration
Ultra Low Power Consumption:
Active Mode:
Doze Mode:
Sleep Mode:
170 uA
18 uA
2.5 uA
400KHz I2C Serial Interface
Four programmable I2C Sub-Addresses
Input Levels Compatible with 1.8V Host Processors
Open Drain NIRQ Interrupt pin
Three (3) Reset Sources: POR, NRST pin, Soft
Reset
-40°C to +85°C Operation
Compact Size: 3 x 3mm Thin QFN package
Pb & Halogen Free, RoHS/WEEE compliant
APPLICATIONS
•
•
•
•
•
SAR Compliant Systems
Notebooks
Tablets
Mobile Phones
Mobile Hot Spots
ORDERING INFORMATION
Semtech P/N
SX9300IULTRT
Note1
SX9300EVK
Package
Marking
QFN-20
ZM5C
Eval. Kit
Note 1: Quantities are ordered in 3K units per Reel
TYPICAL APPLICATION CIRCUIT
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SX9300
Ultra Low Power, Dual Channel
Smart Proximity SAR Compliant Solution
WIRELESS & SENSING PRODUCTS
Datasheet
Table of Contents
GENERAL DESCRIPTION ........................................................................................................................ 1
KEY PRODUCT FEATURES..................................................................................................................... 1
APPLICATIONS....................................................................................................................................... 1
ORDERING INFORMATION...................................................................................................................... 1
TYPICAL APPLICATION CIRCUIT ............................................................................................................ 1
GENERAL DESCRIPTION............................................................................................................... 5
1
1.1
1.2
1.3
1.4
2
Pin Diagram
Marking information
Pin Identification
Acronyms
5
5
6
6
ELECTRICAL CHARACTERISTICS ................................................................................................. 7
2.1
2.2
2.3
3
Absolute Maximum Ratings
Recommended Operating Conditions
Thermal Characteristics
7
7
7
FUNCTIONAL DESCRIPTION ........................................................................................................ 11
3.1
Introduction
3.1.1
General
3.1.2
Parameters and Configuration
3.1.3
Sensor Proximity Adjustment
3.2
Scan Period
3.3
Operational Modes
3.4
I2C interface
3.5
Configuration
3.6
Reset
3.6.1
Power-up
3.6.2
NRST
3.6.3
Software Reset
3.7
Interrupt
3.7.1
Power-up
3.7.2
NIRQ Clearing
4
11
11
11
11
11
12
12
13
13
13
14
14
15
15
15
PIN DESCRIPTIONS ..................................................................................................................... 16
4.1
4.2
4.3
4.4
4.5
5
Introduction
VDD and SVDD
TXEN
Capacitor Sensing Interface (CS0A, CS0B, CS1A, CS1B, CSG)
Host Interface
4.5.1
NIRQ
4.5.2
SCL, NRST and TXEN
4.5.3
SDA
16
16
16
16
16
16
17
17
DIFFERENTIAL DETECTION AND SAR COMPLIANCE .................................................................. 18
5.1
5.2
Specific Absorption Rate (SAR) Basics
SAR Solution
5.2.1
Set CPS_DEB [5:4] (Debounce)
5.2.2
Set CPS_DELTATRS [3:0] (SAR Delta Detection Threshold)
5.2.3
Set CPS_RATIOTRS [7:0] (SAR Ratio Detection Threshold)
5.2.4
Setting Up The SX9300 To Discriminate Between A Human Body & Inanimate Object
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18
18
18
19
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SX9300
Ultra Low Power, Dual Channel
Smart Proximity SAR Compliant Solution
WIRELESS & SENSING PRODUCTS
Datasheet
6
DETAILED CONFIGURATION DESCRIPTIONS .............................................................................. 20
6.1
6.2
Introduction
Capacitive Sensor (CS0A, CS0B, CS1A, CS1B) Parameters
6.2.1
Set CPS_Digital_GAIN [6:5] (Cap Sensor Gain)
6.2.2
Set CPS_CINR [1:0] (Input Capacitance Range and Resolution)
6.2.3
Set CPS_TRS [4:0] (Detection threshold)
6.2.4
Set CPS_HYST [5:4] (Detection Hysteresis)
6.2.5
Set CPS_AVGDEB[7:6] (Average Pos/Neg Debouncing)
6.2.6
Set CPS_AVGNEGFILT[5:3] & CPS_AVGPOSFILT[2:0] (Average Neg/Pos Filters)
6.2.7
Set CPS_FS[4:3] (Sampling Frequency)
6.2.8
Set CPS_RES[2:0] (Resolution Factor)
6.2.9
Set CPS_AVGTRS[7:0] (Averaging Threshold)
6.3
Additional Parameter Settings
6.3.1
Set CPS_PERIOD[6:4] (Scan Period)
6.3.2
Set CPS_EN [3:0] (Enable Capacitive Sensor Inputs)
6.3.3
Set IRQ_Enable [6:3] (Enable Interrupt Sources)
7
20
20
20
20
21
22
22
22
23
23
23
24
24
24
24
I2C INTERFACE ........................................................................................................................... 25
7.1
7.2
7.3
7.4
8
I2C Write
I2C Read
Register Overview
SAR Sensor Design
25
26
27
31
PACKAGING INFORMATION ........................................................................................................ 32
8.1
8.2
Package Outline Drawing
Land Pattern
32
33
LIST OF FIGURES
Figure 1: Pin Diagram .............................................................................................................................................5
Figure 2: QFN Marking Information .......................................................................................................................5
Figure 3: I2C Start and Stop timing .....................................................................................................................10
Figure 4: I2C Data timing ......................................................................................................................................10
Figure 5 Scan Period.............................................................................................................................................11
Figure 6: Power-up vs. NIRQ ................................................................................................................................13
Figure 7: Hardware Reset .....................................................................................................................................14
Figure 8: Software Reset ......................................................................................................................................14
Figure 9: NIRQ Output Simplified Diagram ........................................................................................................16
Figure 10: SCL/TXEN/NRST .................................................................................................................................17
Figure 11: SDA Simplified Diagram .....................................................................................................................17
Figure 12: I2C Write...............................................................................................................................................25
Figure 13: I2C Read ...............................................................................................................................................26
Figure 14: Typical SAR Capacitive Sensor .........................................................................................................31
Figure 15: Package Outline Drawing ...................................................................................................................32
Figure 16: Package Land Pattern ........................................................................................................................33
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SX9300
Ultra Low Power, Dual Channel
Smart Proximity SAR Compliant Solution
WIRELESS & SENSING PRODUCTS
Datasheet
LIST OF TABLES
Table 1: Pin Description .........................................................................................................................................6
Table 2: Absolute Maximum Ratings ....................................................................................................................7
Table 3: Recommended Operating Conditions ....................................................................................................7
Table 4: Thermal Characteristics...........................................................................................................................7
Table 5: Electrical Characteristics.........................................................................................................................9
Table 6: I2C Timing Specification ........................................................................................................................10
Table 7: I2C Sub-Address Selection....................................................................................................................12
Table 8: Detection Debounce Control .................................................................................................................18
Table 9: Delta Threshold Selection .....................................................................................................................18
Table 10: CPS_Digital_GAIN ................................................................................................................................20
Table 11: CINPUT Range and Resolution Register ...............................................................................................20
Table 12: Cap Sensor Threshold .........................................................................................................................21
Table 13: CPS_HYST .............................................................................................................................................22
Table 14: CPS_AVGDEB .......................................................................................................................................22
Table 15: Sampling Frequency Control ..............................................................................................................23
Table 16: CPS Resolution Factor.........................................................................................................................23
Table 17: Scan Period ...........................................................................................................................................24
Table 18: Register Overview ................................................................................................................................30
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SX9300
Ultra Low Power, Dual Channel
Smart Proximity SAR Compliant Solution
WIRELESS & SENSING PRODUCTS
Datasheet
1 GENERAL DESCRIPTION
1.1
Pin Diagram
Figure 1: Pin Diagram
1.2
Marking information
ZM5C
yyww
xxxx
yyww= Date Code
xxxx = Lot Number
Figure 2: QFN Marking Information
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SX9300
Ultra Low Power, Dual Channel
Smart Proximity SAR Compliant Solution
WIRELESS & SENSING PRODUCTS
Datasheet
1.3
Pin Identification
Pin
Number
Name
Type
Description
1
CSG
Analog
Capacitive Sensor Guard
2
CS1B
Analog
Capacitive Sensor, 1B
3
CS1A
Analog
Capacitive Sensor, 1A
4
CS0B
Analog
Capacitive Sensor, 0B
5
CS0A
Analog
Capacitive Sensor, 0A
6
GND
Ground
Ground
7
NC
Not Used
Do Not Connect
8
NC
Not Used
Do Not Connect
9
NC
Not Used
Do Not Connect
10
NC
Not Used
Do Not Connect
11
VDD
Power
SX9300 Core Power
12
SVDD
Power
Host serial port supply voltage. Must be less than or equal to VDD. NOTE:
During power-up or power-down, SVDD must be less than or equal to VDD
13
NIRQ
Digital Output
14
SCL
Digital Input
I2C Clock, requires pull up resistor to SVDD
15
SDA
Digital I/O
I2C Data, requires pull up resistor to SVDD
16
TXEN
Input
Transmit Enable, active HIGH (Tie to SVDD if not used).
17
NRST
Input
External reset, active LOW, requires pull up resistor to SVDD
18
A1
Digital Input
I2C Sub-Address, connect to GND or VDD
19
A0
Digital Input
I2C Sub-Address, connect to GND or VDD
20
GND
Ground
Ground
DAP
GND
Ground
Exposed Pad. Connect to Ground
Interrupt request, active LOW, requires pull-up resistor to SVDD
Table 1: Pin Description
1.4
Acronyms
DAP
SAR
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Die Attach Paddle
Specific Absorption Rate
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SX9300
Ultra Low Power, Dual Channel
Smart Proximity SAR Compliant Solution
WIRELESS & SENSING PRODUCTS
Datasheet
2 ELECTRICAL CHARACTERISTICS
2.1
Absolute Maximum Ratings
Stresses above the values listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only
and functional operation of the device at these, or any other conditions beyond the “Recommended Operating Conditions”, is not implied.
Exposure to Absolute Maximum Rating conditions for extended periods may affect device reliability and proper functionality.
Parameter
Symbol
MIN
MAX
VDD
-0.5
6.0
SVDD
-0.5
6.0
Input voltage (non-supply pins)
VIN
-0.5
VDD+0.3
Input current (non-supply pins)
IIN
-10
10
Operating Junction Temperature
TJCT
-40
125
Reflow temperature
TRE
Storage temperature
TSTOR
-50
ESDHBM
8
UNIT
Supply Voltage
ESD HBM (Human Body model, to JESD22-A114)
260
V
mA
°C
150
kV
Table 2: Absolute Maximum Ratings
2.2
Recommended Operating Conditions
Parameter
Symbol
Supply Voltage
Ambient Temperature Range
MIN
MAX
VDD
2.7
5.5
SVDD
1.65
VDD
TA
-40
85
UNIT
V
°C
Table 3: Recommended Operating Conditions
NOTE: During power-up or power-down, SVDD must be less than or equal to VDD
2.3
Thermal Characteristics
Parameter
Symbol
Thermal Resistance – Junction to Air (Static Airflow)
MIN
θJA
Typical
MAX
34
UNIT
°C/W
Table 4: Thermal Characteristics
Note: Theta JA is calculated from a package in still air, mounted to 3" x 4.5", 4 layer FR4 PCB with
thermal vias under exposed pad per JESD51 standards.
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SX9300
Ultra Low Power, Dual Channel
Smart Proximity SAR Compliant Solution
WIRELESS & SENSING PRODUCTS
Datasheet
Electrical Specifications
All values are valid within the operating conditions unless otherwise specified.
Parameter
Symbol
Conditions
MIN
TYP
ISLEEP
Power down, all analog circuits
shut down.
(I2C listening)
2.5
Doze
IDOZE
CPS_PERIOD = 200mS
DozePeriod = 2xCps_Period
CPS_FS = 167KHz
CPS_RES = Medium
VDD = 5 volt
18
Active (See Note i)
IACTIVE
CPS_PERIOD = 30mS
CPS_FS = 167kHz
CPS_RES = Medium.
VDD = 5 volt
MAX
UNIT
Current consumption
Sleep Mode
uA
170
Outputs: SDA, NIRQ
Output Current at Output Low
Voltage
IOL
Maximum Output LOW Voltage
VOL(Max)
VOL = 0.4V
6
mA
SVDD > 2V
0.4
SVDD ≤ 2V
0.2 x SVDD
V
Inputs: SCL, SDA, TXEN
Input logic high
VIH
0.8 x SVDD
SVDD + 0.3
Input logic low
VIL
-0.3
0.25 x SVDD
Input leakage current
IL
-1
1
V
CMOS input
VHYS
SVDD> 2V
0.05x
SVDD
SVDD≤ 2V
0.1x
SVDD
Hysteresis
TXEN measurements
TXENACTDLY
Delay to when the SX9300
actually begins
measurements from when
TXEN becomes active
uA
V
µS
100
Input: A0, A1
Input logic high
VIH
0.7 x VDD
VDD + 0.3
Input logic low
VIL
-0.3
0.3 x VDD
V
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Ultra Low Power, Dual Channel
Smart Proximity SAR Compliant Solution
WIRELESS & SENSING PRODUCTS
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Input: NRST
Input logic high
SVDD> 2V
0.7 x
SVDD
SVDD ≤ 2V
0.75 x
SVDD
VIH
Input logic low
SVDD + 0.3
V
SVDD> 2V
0.6
SVDD ≤ 2V
0.3 x SVDD
VIL
Start-up
Power-up time
TPOR
1
mS
TRESETPW
20
nS
NRST
NRST minimum pulse width
Table 5: Electrical Characteristics
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SX9300
Ultra Low Power, Dual Channel
Smart Proximity SAR Compliant Solution
WIRELESS & SENSING PRODUCTS
Datasheet
Parameter
Symbol
Conditions
MIN
TYP
MAX
UNIT
400
kHz
I2C Timing Specifications
SCL clock frequency
fSCL
SCL low period
tLOW
1.3
SCL high period
tHIGH
0.6
Data setup time
tSU;DAT
100
Data hold time
tHD;DAT
0
Repeated start setup time
tSU;STA
0.6
Start condition hold time
tHD;STA
0.6
Stop condition setup time
tSU;STO
0.6
Bus free time between stop and start
tBUF
1.3
Input glitch suppression
tSP
uS
Note (1)
50
nS
Note (1) -- Minimum glitch amplitude is 0.7VDD at High level and Maximum 0.3VDD at Low level.
Table 6: I2C Timing Specification
Note: All timing specifications, refer to Figure 3, Figure 4, and Table 6
Figure 3: I2C Start and Stop timing
Figure 4: I2C Data timing
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SX9300
Ultra Low Power, Dual Channel
Smart Proximity SAR Compliant Solution
WIRELESS & SENSING PRODUCTS
Datasheet
3 FUNCTIONAL DESCRIPTION
3.1
3.1.1
Introduction
General
The SX9300 is the world’s first SAR controller that is designed to detect proximity, differentiating between a
human body and an inanimate object. The resulting detection is used in portable electronic devices to reduce
and control radio-frequency (RF) emission power in the presence of a human body, enabling significant
performance advantages for manufacturers of electronic devices with EMF radiation sources to meet stringent
emission regulations' criteria and Specific Absorption Rate (SAR) standards.
3.1.2
Parameters and Configuration
The SX9300 allows the user full parameter customization for Sensor sensitivity, hysteresis, and detection
thresholds. If custom parameters are used by the customer, these parameters must be uploaded by the host
immediately following boot-up or after a reset.
3.1.3 Sensor Proximity Adjustment
Capacitive proximity detection is directly proportional to the SX9300 internal gain and threshold settings, and
external sensor area to optimize proximity detection distance. A longer Proximity detection range can be
accomplished without changing the capacitive sensor size, by using a high sensitivity setting and/or lower signal
threshold setting for proximity detection.
3.2
Scan Period
The Scan period determines the minimum SAR detection reaction time of the SX9300 and can be varied by the
host from 30ms to approximately 400ms. SAR detection reaction time is proportional to the Scan period and
inversely proportional to power consumption, so longer Scan periods corresponds to lower power, but also to
longer detection reaction times.
CS0B
CS0A
CS1B
CS1A
CS0B
CS0A
The Scan period of the SX9300 is defined by two periods: Sensing and Idle. During the Sensing period, all
enabled CS inputs, from CS0A to CS1B are sampled and any detection reported via the I2C bus (via I2C register
polling or NIRQ). The Sensing period is variable and is proportional to the Scan Frequency and Resolution
settings in the Cap Sensing Control Registers. During the Idle period, the SX9300 the analog circuits are placed
in standby and the idle timer is initiated. Upon expiry of the idle timer, a new Scan period cycle begins.
Figure 5 Scan Period
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Ultra Low Power, Dual Channel
Smart Proximity SAR Compliant Solution
WIRELESS & SENSING PRODUCTS
Datasheet
3.3
Operational Modes
The SX9300 has four (4) operational modes: Active, Doze, Sleep, and Commanded. These modes enable
tradeoffs between SAR detection reaction time and power consumption.
Active: Active mode has the shortest scan periods, with a typical SAR detection reaction time of 30ms. In this
mode, all enabled sensors are scanned and information data is processed within this interval. The Active scan
period is user configurable and can be extended to a maximum period of 400ms. See CPS_PERIOD register in
Section 7.3, (I2C Register Overview) below.
Doze: Doze mode is by default, enabled in the SX9300. The Doze mode period is user configurable (see
Section 7.3, I2C Register Overview) and can be used to extend the scan period out to 6.4 seconds for very low
power consumption applications at the expense of very long SAR detection reaction times (6.4 seconds).
In some applications, the SAR detection reaction time needs to be fast, when a human body is present, but can
be slow when SAR detection has not been active for a while. When the SX9300 has not detected an object for a
specific time, it will automatically change modes from Active to Doze reducing power. This time-out period is
determined by the CPS_DOZEPERIOD which can be configured by the user or turned OFF (CPS_DOZEEN) if
not required.
Proximity detection on any sensor will cause the SX9300 to leave Doze mode and re-enter Active mode.
Sleep: Sleep mode places the SX9300 in its lowest power mode, disabling all sensor scanning and setting the
idle period to continuous. In this mode, only the I2C serial bus is active.
Commanded: The commanded mode is perhaps the SX9300’s most useful feature. The TXEN input enables
the measurement of the SAR channels when HIGH, likewise when the TXEN input is LOW, the SX9300 is in the
Sleep mode. Specifically, on the rising edge of TXEN the SX9300 will begin measuring the SAR channels
beginning with the lowest enabled channel repeating the measurement cycle at programmed rates
(CPS_PERIOD) so long as TXEN remains HIGH. When TXEN goes LOW the current measurement sequence
will complete and then measurement will cease until the next rising edge of TXEN.
3.4
I2C interface
The I2C serial interface is configured as a slave device, operates at speeds up to 400 kHz and serves as the
Host interface to the SX9300.
The SX9300 has two I/O pins (A0 and A1) that provides for four possible, user selectable I2C addresses:
A1
0
0
1
1
A0
0
1
0
1
Address
0x28
0x29
0x2A
0x2B
Table 7: I2C Sub-Address Selection
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SX9300
Ultra Low Power, Dual Channel
Smart Proximity SAR Compliant Solution
WIRELESS & SENSING PRODUCTS
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3.5
Configuration
If the application requires customization, the SX9300 configuration registers can be changed over the I2C bus.
Some I2C addressable registers are used to read sensor status and information, while other (configuration)
registers allow the host to take control of the SX9300. Via the configuration registers, the host can command an
operational mode change or modify the active sensors. These user programmable configuration registers are
volatile, therefore during a power-down or reset event, they lose all user programmed content, requiring the host
to re-write the I2C registers after the event.
3.6
Reset
A Reset to the SX9300 is performed by any one of the following methods:
- Power-up
- NRST pin
- Software reset
3.6.1
Power-up
During a power-up condition, the NIRQ output is HIGH until VDD has met the minimum input voltage requirements
and a TPOR time has expired upon which, NIRQ asserts to a LOW condition indicating the SX9300 is initialized.
The Host is required to perform an I2C read to clear this NIRQ status. The SX9300 is then ready for normal I2C
communication and is operational.
Figure 6: Power-up vs. NIRQ
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SX9300
Ultra Low Power, Dual Channel
Smart Proximity SAR Compliant Solution
WIRELESS & SENSING PRODUCTS
Datasheet
3.6.2
NRST
When NRST is asserted LOW and then HIGH, the SX9300 will reset its internal registers and will become active
after period, TPOR. If a hardware reset control output is not available to drive NRST, then this pin must be pulled
high to SVDD.
Figure 7: Hardware Reset
3.6.3
Software Reset
The host can perform software resets by writing to the I2CSoftReset register (see Section 7.3 for additional
information). The NIRQ output will be asserted LOW and the Host is required to perform an I2C read to clear this
NIRQ status.
Figure 8: Software Reset
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SX9300
Ultra Low Power, Dual Channel
Smart Proximity SAR Compliant Solution
WIRELESS & SENSING PRODUCTS
Datasheet
3.7
Interrupt
Interrupt sources are disabled by default upon power-up and resets, and thus must be enabled by the host (apart
from RESET IRQ). Any or all of the following interrupts can be enabled by writing a “1” into the appropriate
locations within the IRQ_Enable register (see Section 7.3 for details):
• Body detected
• Completed Compensation
• Completed Conversion
The interrupt status can be read from register IRQStat for each of these interrupt sources (see Section 7.3 for
details).
3.7.1
Power-up
During initial power-up, the NIRQ output is HIGH. Once the SX9300 internal power-up sequence has completed,
NIRQ is asserted LOW, signaling that the SX9300 is ready. The host must perform a read to IRQStat to
acknowledge that the status is read and the SX9300 will clear the interrupt and release the NIRQ line.
3.7.2
NIRQ Clearing
The NIRQ can be asserted in either the Active or Doze mode during a scan period.
automatically cleared after the Host performs a read of the IRQStat I2C register.
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The NIRQ will be
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SX9300
Ultra Low Power, Dual Channel
Smart Proximity SAR Compliant Solution
WIRELESS & SENSING PRODUCTS
Datasheet
4 PIN DESCRIPTIONS
4.1
Introduction
This section describes the SX9300 pin functionality, pin protection, whether or not the pins are analog or digital,
and if they require pull-up resistors. There is ESD protection on all SX9300 I/O.
4.2
VDD and SVDD
These are the device supply voltages. VDD is the supply voltage for the internal core and I/O. SVDD is the
supply voltage for the I2C serial interface. NOTE: SVDD MUST be equal or lower than VDD.
4.3
TXEN
This signal can be used in many applications if a conversion trigger/enable is needed. This input pin
synchronizes the Capacitance Sensing inputs in systems that need to (for example) transmit RF signals. When
this signal is active, SX9300 immediately performs capacitive measurements. If this input becomes inactive
during the middle of a measurement, the SX9300 will complete all remaining measurements and will enter sleep
mode until TXEN goes active again.
4.4
Capacitor Sensing Interface (CS0A, CS0B, CS1A, CS1B, CSG)
The Capacitance Sensor input pins CS0A, CS0B, CS1A and CS1B are connected directly to the Capacitor
Sensing Interface circuitry which converts the sensed capacitance into digital values. The Capacitive Sensor
Guard (CSG) output provides a guard reference to minimize the parasitic sensor pin capacitances to ground.
Capacitance sensor pins which are not used must be left open-circuited. Additionally, CS pins must be
connected directly to the capacitive sensors using a minimum length circuit trace to minimize external “noise”
pick-up.
The capacitance sensor and capacitive sensor guard pins are protected from ESD events to VDD and GROUND.
4.5
Host Interface
The Host Interface consists of: NIRQ, NRST, SCL, SDA, and TXEN. These signals are discussed below.
4.5.1
NIRQ
The NIRQ pin is an open drain output that requires an external pull-up resistor (1..10 KOhm). The NIRQ pin is
protected from ESD events to SVDD and GROUND.
SVDD
SVDD
R_INT
NIRQ
NIRQ to Host
INT
SX9300
Figure 9: NIRQ Output Simplified Diagram
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4.5.2
SCL, NRST and TXEN
The SCL, NRST and TXEN pins are high impedance input pins that require an external pull-up resistor (1..10
kOhm). It is possible to connect NRST and TXEN Host output drivers directly without the requirement for a pullup resistor if driven from a push-pull host output. These pins are protected from ESD events to SVDD and
GROUND.
SVDD
SVDD
R
SCL_IN/TXEN_IN/NRST_IN
From Host
SCL/TXEN/NRST
Figure 10: SCL/TXEN/NRST
4.5.3
SDA
SDA is an I/O pin that requires an external pull-up resistor (1..10 KOhm). The SDA I/O pin is protected to SVDD
and GROUND.
SVDD
SVDD
R_SDA
SDA
To/From Host
SDA_IN
SDA_OUT
Figure 11: SDA Simplified Diagram
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5 DIFFERENTIAL DETECTION AND SAR COMPLIANCE
5.1
Specific Absorption Rate (SAR) Basics
SAR is a measure of the rate at which energy is absorbed by the body when exposed to a radio frequency (RF)
electromagnetic field; although, it can also refer to absorption of other forms of energy by tissue, including
ultrasound. It is defined as the power absorbed per mass of tissue and has units of watts per kilogram (W/kg).
SAR is usually averaged either over the whole body, or over a small sample volume (typically 1g or 10g of
tissue). The value cited is then the maximum level measured in the body part studied over the stated volume or
mass.
The FCC requires that cell phone manufacturers conduct their SAR testing to include the most severe, worstcase (and highest power) operating conditions for all the frequency bands used in the USA for that cell phone.
The SAR values recorded on the FCC’s authorization and in the cell phone manual to demonstrate compliance
with Commission rules indicate only the highest single measurement taken for each frequency range that the
particular model uses. FCC approval means that the device will never exceed the maximum levels of consumer
RF exposure permitted by federal guidelines, but it does not indicate the amount of RF exposure consumers
experience during normal use of the device. While only the maximum SAR values are used for FCC approval, all
test reports submitted by the manufacturer are available in full for public inspection on the Commission’s website.
5.2
SAR Solution
A SAR measurement consists of taking two sets of capacitive sensor data. In this case, each sensor must have
recognized proximity detection. The two sets of data are then combined within the SX9300 as both a “ratio” of
the data and a difference or “delta” of the data. The measured capacitance data can represent a very low level
of capacitance. Therefore insuring that the signal is detected for a number of samples will minimize false
triggers. The SX9300 includes the ability to “debounce” the detected data for up to 8 samples.
5.2.1 Set CPS_DEB [5:4] (Debounce)
The register for the SAR debounce control: Bits [5:4] set the number of debounce samples.
BITS
5
4
DEBOUNCE
SAMPLES
0
0
1
1
0
1
0
1
None
2
4
8
Table 8: Detection Debounce Control
5.2.2 Set CPS_DELTATRS [3:0] (SAR Delta Detection Threshold)
The register for the SAR Delta Threshold Control is at: Bits [3:0] and is used to set Delta Detection Threshold.
The Delta measurement is the capacitive difference measurement between the two SAR Sensing Capacitors
(Sensor B – Sensor A).
Reg
value
0000
0001
0010
0011
0100
0101
0110
0111
Threshold
Value
0
1
3
5
10
15
20
25
Reg
value
1000
1001
1010
1011
1100
1101
1110
1111
Threshold
Value
30
35
40
45
50
55
60
70
Table 9: Delta Threshold Selection
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5.2.3 Set CPS_RATIOTRS [7:0] (SAR Ratio Detection Threshold)
The register for the SAR Ratio Threshold Control is at: 0x10. Bits [7:0] are used to set the SAR RATIO
Threshold for the SX9300. The determination of the SAR Ratio Detection Threshold must be determined
experimentally, but will be stable for a given design
5.2.4
Setting Up The SX9300 To Discriminate Between A Human Body & Inanimate Object
An accurate discrimination between a human body and inanimate object can be obtained using the SX9300. It is
important that the sensor pair areas are identical (in area, not necessarily in shape, see Section 7.4 for
information as to how to design a successful SAR capacitive sensor). This involves a careful set-up between the
following two registers: Delta and Ratio Thresholds. The set-up of these two registers is as follows:
With the customer’s system set onto a table, bring a hand to the desired detection distance from the sensor.
Set the Delta threshold limit until a “detection” is reported by the SX9300
Set the Ratio threshold limit until a “detection” is reported by the SX9300
Remove the hand and test with a number of inanimate objects to determine if the SX9300 successfully rejects
them from reporting. If the SX9300 reports any of them as a “detection”, then raise the Delta threshold limit until
it stops being reported and confirm that the human body is still reported (note: you will lose a bit of detection
range when you raise threshold limits).
If you cannot determine a successful setting that simultaneously rejects inanimate objects and detects a human
body, then you must raise the Ratio threshold limit. Repeat 4) until a solution is determined.
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6 DETAILED CONFIGURATION DESCRIPTIONS
6.1
Introduction
The SX9300 is the first Smart Proximity SAR Compliant sensor that solves the human body versus inanimate
object problem that designers of mobile appliances face every day. It requires only small external sensors plus
some minor set-up commands to provide a robust SAR solution. The SX9300 comes with factory default settings
that are appropriate for most general applications, however a full complement of registers are accessible to the
user to enable application customization and optimization.
6.2
Capacitive Sensor (CS0A, CS0B, CS1A, CS1B) Parameters
The SX9300 sensor has default parameters for the Capacitive Sensors that provides a quick and initial starting
point to achieve SAR compliance. However, because of unique sensor sizes and sensor locations, it is possible
to achieve higher and more robust performance with minor changes to these default parameters. In general only
a few registers require changes to their default parameters to achieve improved performance. These registers
are:
6.2.1
Set CPS_Digital_GAIN [6:5] (Cap Sensor Gain)
The address for the (capacitive) sensor gain is: Bits [6:5] provide for four (4) gain settings as shown below:
Bits
6
0
0
1
1
5
0
1
0
1
Gain
x1
x2
x4
x8
Table 10: CPS_Digital_GAIN
6.2.2
Set CPS_CINR [1:0] (Input Capacitance Range and Resolution)
The register for the input capacitance full scale range and resolution is: Bits [1:0] provide set ability over the
expected maximum sensed capacitance. A setting of 00 on these bits provides for the largest capacitance
measurement range, but is not as sensitive for the longest proximity distance, while the setting of 11 provides for
the smallest capacitive measurement range, and provides the longest proximity distance. The table for this
register is shown below:
Bits
1
0
0
1
1
0
0
1
0
1
CINPUT Range and Resolution
Large
Medium-Large
Medium-Small
Small
Table 11: CINPUT Range and Resolution Register
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6.2.3
Set CPS_TRS [4:0] (Detection threshold)
This register defines the detection threshold for all sensors and the details are shown below. Lower thresholds
provide longer proximity detection distances but are more susceptible to noise, while higher threshold values
provide immunity to noise, but results in shorter proximity detection range. The default value for this register is
[00000].
BITS
4
3
2
1
0
THRESHOLD VALUE
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
20
40
60
80
100
120
140
160
180
200
220
240
260
280
300
350
400
450
500
600
700
800
900
1000
1100
1200
1300
1400
1500
1600
1700
Table 12: Cap Sensor Threshold
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6.2.4
Set CPS_HYST [5:4] (Detection Hysteresis)
This register defines the detection hysteresis for all sensors. Hysteresis for the SAR sensors provides an
important function in that it keeps the SX9300 from providing “oscillating” results when detection levels are close
to threshold. The register details are shown below.
Bits
5
0
0
1
1
4
0
1
0
1
DETECTION HYSTERESIS
32
64
128
256
Table 13: CPS_HYST
6.2.5 Set CPS_AVGDEB[7:6] (Average Pos/Neg Debouncing)
Use of debounce in the SX9300 is recommended as it will reduce the effects of extraneous noise for reported
detection. The SX9300 includes several conditions for debounce: Close, Far, and Data Detection.
Bits
7
0
0
1
1
6
0
1
0
1
AVERAGE POS/NEG DEBOUNCING
OFF
2 Samples
4 Samples
8 Samples
Table 14: CPS_AVGDEB
6.2.6
Set CPS_AVGNEGFILT[5:3] & CPS_AVGPOSFILT[2:0] (Average Neg/Pos Filters)
The SX9300 includes circuitry to average out the detected signals. These detected signals can be both positive
and negative, and so there are registers to control both the positive and negative averaging filter coefficients.
There are eight (8) settings possible in each of these filters ranging from OFF up to highest filtering. Use of
these filters is recommended for noisy environment and represents a tradeoff detection response versus false
triggering. See CPS_AVGNEGFILT and CPS_AVGPOSFILT for register and bit locations.
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6.2.7 Set CPS_FS[4:3] (Sampling Frequency)
The capacitance sampling frequency can be changed in CPS_CTRL2 if the environment is particularly noisy.
Changing this frequency affects the Capacitance Sensing period. It is recommended to use the 167 kHz
sampling frequency.
Bits
4
0
0
1
1
3
0
1
0
1
SAMPLING FREQUENCY
83 kHz
125 kHz
167 kHz
Reserved, do not use
Table 15: Sampling Frequency Control
6.2.8 Set CPS_RES[2:0] (Resolution Factor)
The CPS Resolution factor has 8 possible settings that range from coarsest to very fine that controls the total
number of measurements per sensor in a Scan Period. Along with the CPS Sampling Frequency, changing this
register affects the SX9300 Sensing Period. This register is located in CPS_CTRL2.
Bits
1
0
RESOLUTION
1
0
0
1
1
0
0
1
0
1
0
Coarsest
Very Coarse
Coarse
Medium Coarse
Medium
1
0
1
Fine
1
1
0
Very Fine
1
1
1
Finest
2
0
0
0
0
Table 16: CPS Resolution Factor
6.2.9
Set CPS_AVGTRS[7:0] (Averaging Threshold)
The SX9300 performs averaging on all capacitive measurements to determine when to perform a calibration
cycle. The CPS_AVGTRS register is used to set an 8-bit positive and negative threshold that determines when a
calibration is internally requested. Typically the user would set this register to be between 10000000 [7:0] to
11000000 [7:0] which corresponds to ½ to ¾ of the system dynamic range.
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6.3
Additional Parameter Settings
Further application customization is possible to control scan period, enabled sensors and individual sensor
interrupts are also possible. Scan period affects both power dissipation and detection reaction time.
6.3.1
Set CPS_PERIOD[6:4] (Scan Period)
This register controls the scan period of the SX9300 over a range of 30ms to 400ms.
Bits
5
4
Scan PERIOD (ms)
1
0
0
1
1
0
0
1
0
1
0
30
60
90
120
150
1
0
1
200
1
1
0
300
1
1
1
400
6
0
0
0
0
Table 17: Scan Period
6.3.2
Set CPS_EN [3:0] (Enable Capacitive Sensor Inputs)
If one set of SAR capacitive sensors is not required, they can be disabled in this register. Each bit in this register
corresponds to a specific sensor input. A logic “1” enables the capacitive sensor input, while a logic “0” disables
a capacitive input. INPUTS MUST BE DISABLED IN PAIRS.
CS0A & CS0B = Bits [1:0]
CS1A & CS1B = Bits [3:2]
6.3.3 Set IRQ_Enable [6:3] (Enable Interrupt Sources)
There are a number of interrupt sources that the SX9300 can report. A logic “1” in the specific location will
enable the specific interrupt as shown below.
SARIRQEN [6]: Enables the SAR Proximity Detection IRQ
SARRLSIRQEN [5]: Enables the SAR Proximity No Detect IRQ
COMPDONEIRQEN [4]: Enables the Compensation Done Notification IRQ
CONVIRQEN [3]: Enables the Conversion Completion Done Notification IRQ
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7 I2C INTERFACE
The I2C implemented on the SX9300 is compliant with:
- Standard (100kb/s) and fast mode (400kb/s)
- I2C standard slave mode
- 7 bit address (default is 0x28 assuming A1=A0=0).
The host can use the I2C to read and write data at any time, and these changes are effective immediately.
Therefore the user should ideally disable the sensor before changing settings, or discard the results while
changing (Section 3.2).
There are four types of I2C registers:
- Control and Status (read). These registers give information about the status of the capacitive sensors
- Operation Control (read/write). These registers control Operating Modes.
- Cap Sensor Control and Parameters (read/write)
- Cap Sensor Data Read Back (read)
The I2C can be used to read and write from a start address and then perform read or writes sequentially, and the
address increments automatically.
Supported I2C access formats are described in the next sections.
7.1
I2C Write
The format of the I2C write is given in Figure 12. After the start condition [S], the slave address (SA) is sent,
followed by an eighth bit (‘0’) indicating a Write. The SX9300 then Acknowledges [A] that it is being addressed,
and the Master sends an 8 bit Data Byte consisting of the SX9300 Register Address (RA). The Slave
Acknowledges [A] and the master sends the appropriate 8 bit Data Byte (WD0). Again the Slave Acknowledges
[A]. In case the master needs to write more data, a succeeding 8 bit Data Byte will follow (WD1), acknowledged
by the slave [A]. This sequence will be repeated until the master terminates the transfer with the Stop condition
[P].
Figure 12: I2C Write
The register address is incremented automatically when successive register data (WD1...WDn) is supplied by the
master.
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7.2
I2C Read
The format of the I2C read is given in Figure 13. After the start condition [S], the slave address (SA) is sent,
followed by an eighth bit (‘0’) indicating a Write. The SX9300 then Acknowledges [A] that it is being addressed,
and the Master responds with an 8-bit Data consisting of the Register Address (RA). The Slave Acknowledges
[A] and the master sends the Repeated Start Condition [Sr]. Once again, the slave address (SA) is sent,
followed by an eighth bit (‘1’) indicating a Read. The SX9300 responds with an Acknowledge [A] and the read
Data byte (RD0). If the master needs to read more data it will acknowledge [A] and the SX9300 will send the
next read byte (RD1). This sequence can be repeated until the master terminates with a NACK [N] followed by a
stop [P].
Figure 13: I2C Read
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7.3
Register Overview
Add Reg
General Control & Status
0x00 IRQStat
0x01
TchCmpStat
Acc
Bits
Field
R
7
6
5
RESETIRQ
TCHIRQ
RLSIRQ
1
0
0
R/W
4
COMPDONE
0
R
3
2:1
0
7
CONVIRQ
Not Used
TXENSTAT
SARSTAT3
0
00
0
0
6
SARSTAT2
0
5
SARSTAT1
0
4
SARSTAT0
0
3:0
COMPSTAT
1111
7
6
5
4
Not Used
SARIRQEN
SARRLSIRQEN
COMPDONEIRQEN
3
2:0
CONVIRQEN
Not Used
0
000
7
6:4
Not Used
CPS_PERIOD
0
000
3:0
CPS_EN
1111
R/W
7:6
CPS_SH
01
R/W
5:2
1:0
CPS_CINR
R
General Operations Control
0x03 IRQ_Enable
R
R/W
R
Cap Sensing Control
0x06 CPS_CTRL0
0x07
CPS_CTRL1
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Reset
0
0
0
0
0000
00
Function
Reset event occurred
Sensor proximity detected
Sensor detection release
condition interrupt
Compensation
complete.
Writing a one in this bit trigs
a compensation on all
channels
Conversion cycle complete
Not Used
Report TXEN pad status
Determines if proximity has
been detected for the pair
CS1A/CS1B
Determines if a human body
has been detected for the
pair CS1A/CS1B
Determines if a proximity
has been detected for the
pair CS0A/CS0B
Determines if a human body
has been detected for the
pair CS0A/CS0B
Specifies which capacitive
sensor(s)
has
a
compensation pending
Not Used
Enables the detection irq
Enables the release irq
Enables the compensation
irq
Enables the conversion irq
Not Used
Not Used
Scan period :
000: 30 ms
001: 60 ms
010: 90 ms
011: 120 ms
100: 150 ms
101: 200 ms
110: 300 ms
111 : 400 ms
Enables CS0A through
CS1B
CG bias/shield usage.
00 : Off, CG high-Z (off)
01: On(def.)
10: Reserved
11: Reserved
Not used
Capacitance Range:
00: Large
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0x08
0x09
CPS_CTRL2
CPS_CTRL3
R/W
R/W
7
6:5
Not Used
CPS_Digital_GAIN
0
00
4:3
CPS_FS
01
2:0
CPS_RES
000
7
6
5:4
Not Used
CPS_DOZEEN
CPS_DOZEPERIOD
0
1
00
3:2
1:0
Reserved
CPS_RAWFILT
00
00
0x0A
CPS_CTRL4
R/W
7:0
CPS_AVGTRS
00000000
0x0B
CPS_CTRL5
R/W
7:6
CPS_AVGDEB
00
5:3
CPS_AVGNEGFILT
000
2:0
CPS_AVGPOSFILT
000
7:5
Not Used
000
0x0C
CPS_CTRL6
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01: Medium Large
10: Medium Small
11: Small
Not Used
Set Digital gain factor
00: Gain = 1
01: Gain = 2
10: Gain = 4
11: Gain = 8
Sampling frequency
00: 83 kHz
01: 125 kHz
10: 167 kHz (Typical)
11: Reserved
Resolution Control
000: Coarsest
….
100: Medium
….
111: Finest
Not Used
Enables doze mode
When doze is enabled, the
cap sensing period moves
from
CPS_PERIOD
to
CPS_PERIOD * :
00: 2*CPS_PERIOD
01: 4* CPS_PERIOD
10: 8*CPS_PERIOD
11: 16*CPS_PERIOD
Must be 00
Raw filter coefficient
00: off
01: Low
10: Medium
11: High (Max Filtering)
Average pos/neg threshold
= 8 x reg
Average
pos/neg
debouncer:
00: off
01: 2 samples
10: 4 samples
11: 8 samples
Average
negative
filter
coefficient :
000: off
001: Lowest
….
….
111: Highest (Max. Filter)
Average
positive
filter
coefficient :
000: off
001: Lowest
.…
…..
111: Highest (Max. Filter)
Not Used
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0x0D
0x0E
CPS_CTRL7
CPS_CTRL8
Sensor Readback
0x20 CPSRD
0x21
0x22
0x23
0x24
0x25
0x26
0x27
UseMSB
UseLSB
AvgMSB
AvgLSB
DiffMSB
DiffLSB
OffMSB
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CPS_TRS
7
CPS_CMPAUTOOFF
0
6
CPS_CMPTRG
0
5:4
CPS_HYST
00
3:2
CPS_CLSDEB
00
1:0
CPS_FARDEB
00
7:4
CPS_STUCK
0000
3:0
CPS_CMPPRD
0000
R
7:2
Not Used
000000
00
R
1:0
CPSRD
R
7:0
SENSUSEMSB
R
7:0
SENSUSELSB
R
7:0
SENSAVGMSB
R
7:0
SENSAVGLSB
R
7:0
SENSDIFFMSB
R
7:0
SENSDIFFLSB
R/W
7:0
SENSOFFMSB
R/W
R/W
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29
00000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
Defines
the
touch/prox
detection threshold for all
sensors. See Table 12
Disables
the
automatic
compensation trigged by
average
0: compensate channels
independently
1: compensate all channels
when triggered
Detection hysteresis
00: 32
01: 64
10: 128
11: 256
Close debouncer
00: off
01: 2 samples
10: 4 samples
11: 8 samples
Far debouncer
00: off
01: 2 samples
10: 4 samples
11: 8 samples
Stuck at timeout timer :
0000 : off
00XX:
increment
every
CPS_STUCK x 64 active
frames
01XX:
increment
every
CPS_STUCK x 128 active
frames
1XXX: increment every
CPS_STUCK x 256 active
frames
Periodic compensation
0: off
else : increment every
CPS_COMPPRD x 128
active frames
Not Used
Determines which sensor
data will be available in the
next Reg read.
Provides
the
useful
information for monitoring
purposes.
Signed, 2's
complement format
Provides
the
average
information for monitoring
purposes.
Signed, 2's
complement format
Provides the Diff information
for monitoring purposes.
Signed, 2's complement
format
Offset compensation DAC
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SX9300
Ultra Low Power, Dual Channel
Smart Proximity SAR Compliant Solution
WIRELESS & SENSING PRODUCTS
Datasheet
0x28
OffLSB
00000000
R/W
7:0
SENSOFFLSB
0x29
Delta
R
3:0
SENSDELTA
0000
0x2A
Ratio
R
7:0
SENSERATIO
00000000
0x7F
I2CSoftReset
W
7:0
SOFTRESET
00000000
R/W
7:6
5:4
Not Used
CPS_DEB
00
00
3:0
CPS_DELTATRS
0000
7:0
CPS_RATIOTRS
00000000
SAR Mode Registers
0x0F Deb_DeltaTrs
0x10
CPS_RatioTrs
R/W
code. This is writable to
allow forcing some DAC
codes. When written, the
internal DAC code is
updated after the write of
the LSB reg. MSB and LSB
regs should be written in
sequence.
SAR
Value
Delta
(Difference)
reading.
Signed, 2's complement
format (See Register 0x20)
Ratio of the SAR values.
Unsigned. (See Register
0x20)
Write 0xDE and Reset the
chip
Not Used
Data
Debouncing
associated
with
detection/release (Useful in
a noisy environment):
00: off
01: 2 samples
10: 4 samples
11: 8 samples
Defines the delta detection
threshold that’s applied to
all sensors. See Table 9
Defines the ratio detection
threshold applied to all
sensors
Table 18: Register Overview
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SX9300
Ultra Low Power, Dual Channel
Smart Proximity SAR Compliant Solution
WIRELESS & SENSING PRODUCTS
Datasheet
7.4
SAR Sensor Design
This section describes how to properly design SAR sensors. The SAR sensors for the SX9300 can be designed
in a variety of shapes depending on the physical requirements of the system.
In the drawing below, the yellow areas represent copper (conductor) and the gray area represents a nonconductor and is the distance r2 – r1 (spacing between the two copper areas).
Figure 14: Typical SAR Capacitive Sensor
“CSxA” and “CSxB” copper areas refer to the SX9300 sensor inputs.
IMPORTANT NOTE: The “A” and “B” sensors cannot be swapped on the SX9300. The outer copper
area is always the “A” sensor, and the inner copper area is always the “B” sensor. Also, the area of a CSxB
sensor and CSxA sensor must be designed to be nearly equal.
The radius “r1” sets the area of SAR sensor CSxB, while the radius “r3 – r2” sets the area of SAR sensor CSxA.
For circular capacitive sensors shown above where “r1” is very nearly equal to “r2”, then the area of CSxA is
defined by
r3 = √2 x r1
This approximation is also true for square type sensors
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SX9300
Ultra Low Power, Dual Channel
Smart Proximity SAR Compliant Solution
WIRELESS & SENSING PRODUCTS
Datasheet
8 PACKAGING INFORMATION
8.1
Package Outline Drawing
Figure 15: Package Outline Drawing
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SX9300
Ultra Low Power, Dual Channel
Smart Proximity SAR Compliant Solution
WIRELESS & SENSING PRODUCTS
Datasheet
8.2
Land Pattern
Figure 16: Package Land Pattern
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SX9300
Ultra Low Power, Dual Channel
Smart Proximity SAR Compliant Solution
WIRELESS & SENSING PRODUCTS
Datasheet
Semtech 2012
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