ams Datasheet Page 1
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CCS811
Ultra-Low Power Digital Gas Sensor for
Monitoring Indoor Air Quality
The CCS811 is an ultra-low power digital gas sensor solution
which integrates a metal oxide (MOX) gas sensor to detect a
wide range of Volatile Organic Compounds (VOCs) for indoor
air quality monitoring with a microcontroller unit (MCU), which
includes an Analog-to-Digital converter (ADC), and an I²C
interface.
CCS811 is based on ams unique micro-hotplate technology
which enables a highly reliable solution for gas sensors, very
fast cycle times and a significant reduction in average power
consumption.
The integrated MCU manages the sensor driver modes and
measurements. The I²C digital interface significantly simplifies
the hardware and software design, enabling a faster time to
market.
CCS811 supports intelligent algorithms to process raw sensor
measurements to output equivalent total VOC (eTVOC) and
equivalent CO2 (eCO2) values, where the main cause of VOCs is
from humans.
CCS811 supports multiple measurement modes that have been
optimized for low-power consumption during an active sensor
measurement and idle mode extending battery life in portable
applications.
CCS811 is available in a 10 lead 2.7mm x 4.0mm x 1.1mm, 0.6mm
pitch LGA package.
Ordering Information and Content Guide appear at end of
datasheet.
General Description
Page 2 ams Datasheet
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CCS811 − General Description
Key Benefits & Features
The benefits and features of CCS811, Ultra-Low Power Digital
Gas Sensor for Monitoring Indoor Air Quality are listed below:
Figure 1:
Added Value of Using CCS811 Sensor
Applications
This device can be mainly used for indoor air quality
monitoring in:
•Smart phones
•Air cleaners and purifiers
•Smart thermostats
•Home controllers
•Smart accessories and IoT devices
Benefits Features
•Manages the sensor drive modes and
measurements while detecting VOCs •Integrated MCU
•Provides eCO2 level or eTVOC indication with no
host intervention •On-board processing
•Simplifies the hardware and software integration •Standard (100kbit/s) and fast (400kbit/s)
I²C interface
•Extend battery life in portable applications •Optimised low-power modes
•Suitable for small form-factor designs •2.7mm x 4.0mm x 1.1mm LGA package
•Saves up to 60% in PCB footprint •Low component count
•Designed for high volume and reliability
(>5years lifetime) •Proven technology platform
ams Datasheet Page 3
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CCS811 − General Description
Block Diagram
The functional blocks of this device are shown below:
Figure 2:
CCS811 Block Diagram
MOX
Gas Sensor
S+
H-
H+
nINT
nRESET
ADDR
SDA
SCL
VDD
GND
nWAKE
S-
7
2
3
4EP
18910
5
6
MCU
(With Integrated ADC)
PWM
Sense
Pins 4 and 5 mu st be
co nnected togeth er
Page 4 ams Datasheet
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CCS811 − Pin Assignment
Figure 3:
Pin Diagram
Pin Diagram: The Exposed Pad is underneath
Figure 4:
CCS811 LGA Pin Assignment
Pin No. Pin Name Description
1 ADDR
Single address select bit to allow alternate address to be selected
•When ADDR is low the 7 bit I²C address is decimal 90 / hex 0x5A
•When ADDR is high the 7 bit I²C address is decimal 91 / hex 0x5B.
2nRESET
nRESET is an active low input and is pulled up to VDD by default. nRESET is
optional but 4.7k pull-up and/or decoupling of the nRESET pin may be
necessary to avoid erroneous noise-induced resets. This pin will be pulled low
internally during reset.
3nINT
nINT is an active low optional output. It is pulled low by the CCS811 to indicate
end of measurement or a set threshold value has been triggered.
4 PWM Heater driver PWM output. Pins 4 and 5 must be connected together.
5 Sense Heater current sense. Pins 4 and 5 must be connected together.
6VDD Supply voltage.
7nWAKE
nWAKE is an active low input and should be asserted by the host prior to an I²C
transaction and held low throughout.
8NCNo connect
9SDA
SDA pin is used for I²C data. Should be pulled up to VDD with a resistor.
10 SCL SCL pin is used for I²C clock. Should be pulled up to VDD with a resistor.
EP Exposed Pad Connect to ground.
Pin Assignment
Pin 1 Corner
Index Area (Top View)
Pin 1 Corner
Index Area
(Bottom View)
1
5
10
6
7
8
9
4
3
2
ams Datasheet Page 5
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CCS811 − Absolute Maximum Ratings
Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. These are stress
ratings only. Functional operation of the device at these or any
other conditions beyond those indicated under Electrical
Characteristics is not implied. Exposure to absolute maximum
rating conditions for extended periods may affect device
reliability
Figure 5:
Absolute Maximum Ratings
Note(s):
1. The supply voltage VDD is sampled during boot and should not vary during operation.
2. The minimum supply voltage VDD is 1.8V and should not drop below this value for reliable device operation.
3. Sensors are electrically operable in this range, however indoor air quality performance will vary in this range.
Symbol Parameter Min Max Units Comments
Electrical Parameters
VDD (1) Supply Voltage 1.8(2) 3.6 V
IDD Average Supply Current 30 mA In mode 1
IDDPeak Peak Supply Current 54 mA In modes 2 and 3
P Power Consumption 60 mW In mode 1
Electrostatic Discharge
ESDHBM Human Body Model ±2000 V
ESDCDM Charged Device Model ±1000 V
Environmental Conditions
TAMB(3) Ambient Temperature for Operation -40 85 oC
TSTRG Storage Temperature -40 125 oC
RHNC Relative Humidity (non-condensing) 10 95 %
MSL Moisture Sensitivity Level 1 Unlimited max.
floor life time
Absolute Maximum Ratings
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CCS811 − Electrical Characteristics
Figure 6:
Electrical Characteristics
Note(s):
1. The supply voltage VDD is sampled during boot and should not vary during operation
2. The maximum VDD ramp time for Power On is 3ms
3. Typical values for 1.8V supply voltage (VDD)
4. Average Supply Current (IDD) for a sensor measurement once every 60 seconds
5. For SDA and SCL timing refer NXP I²C – bus specification and user manual UM10204
6. Typical values at 25oC and 50% RH
Parameters Conditions Min Typ (6) Max Units
Supply Voltage (VDD) (1), (2) 1.8 3.3 V
Supply Current (IDD) (3)
During measuring at 1.8V 26 mA
Average over pulse cycle(3) at 1.8V 0.7 mA
Sleep Mode at 1.8V 19 µA
Power Consumption
Idle Mode 0 at VDD= 1.8V 0.034 mW
Mode 1 & 4 at VDD= 1.8V 46 mW
Mode 2 at VDD= 1.8V 7mW
Mode 3 at VDD= 1.8V 1.2 mW
Logic High Input (5) nRESET, nWAKE, ADDR VDD -
0.6 VDD V
Logic Low Input (5) nRESET, nWAKE, ADDR 0 0.6 V
Logic High Output nINT VDD -
0.7 V
Logic Low Output nINT 0.6 V
Product Lifetime (LT)(6) In Mode 1 >5 Years
Electrical Characteristics
ams Datasheet Page 7
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CCS811 − Electrical Characteristics
Figure 7:
Timing Characteristics
Note(s):
1. nWAKE should be asserted prior to and during any I²C transaction.
2. Up to 70ms on the first Reset after new application download.
Parameters Conditions Min Typ Max Units
tAPP_START
Time between giving the APP_START
command in boot mode and the device
being ready for new I²C commands
1ms
tWAKE (1) Time between deasserting nWAKE pin
and the device being ready for new I²C
commands
50 µs
tSTART (2)
Time between power on and the device
being ready for new I²C commands 18 20 ms
Time between deasserting nRESET pin or
giving the SW_RESET command and the
device being ready for new I²C
commands
12ms
tDWAKE Minimum time nWAKE should be
de-asserted 20 µs
tDRESET Minimum time nRESET should be
de-asserted 20 µs
tRESET Minimum time nRESET should be
asserted 15 µs
fI²C Frequency of I²C bus supported 10 100 400 kHz
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CCS811 − Detailed Description
Modes of Operation
The CCS811 has 5 modes of operation as follows
•Mode 0: Idle, low current mode
•Mode 1: Constant power mode, IAQ measurement every
second
•Mode 2: Pulse heating mode IAQ measurement every 10
seconds
•Mode 3: Low power pulse heating mode IAQ
measurement every 60 seconds
•Mode 4: Constant power mode, sensor measurement
every 250ms
In Modes 1, 2, 3, the equivalent CO2 concentration (ppm) and
eTVOC concentration (ppb) are calculated for every sample.
•Mode 1 reacts fastest to gas presence, but has a higher
operating current
•Mode 3 reacts more slowly to gas presence but has the
lowest average operating current.
When a sensor operating mode is changed to a new mode with
a lower sample rate (e.g. from Mode 1 to Mode 3), it should be
placed in Mode 0 (Idle) for at least 10 minutes before enabling
the new mode. When a sensor operating mode is changed to a
new mode with a higher sample rate (e.g. from Mode 3 to Mode
1), there is no requirement to wait before enabling the new
mode.
Mode 4 is intended for systems where an external host system
wants to run an algorithm with raw data and this mode provides
new sample data every 250ms. Mode 4 is also recommended
for end-of-line production test to save test time. For additional
information please refer to application note ams AN000373:
CCS811 Factory test procedure.
Note(s): Mode timings are subject to typical 2% tolerance due
to accuracy of internal clock
Early-Life Use (Burn-In)
CCS811 performance in terms of resistance levels and
sensitivities will change during early life use. The change in
resistance is greatest over the first 48 hours of operation.
CCS811 controls the burn-in period allowing eCO2 and eTVOC
readings to be used from first power-on after 60minutes of
operation in modes 1-3.
Detailed Description
ams Datasheet Page 9
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CCS811 − Detailed Description
Conditioning Period (Run-In)
After early-life (Burn-In) use the conditioning period is the time
required to achieve good sensor stability before measuring
VOCs after long idle period.
After writing to MEAS_MODE to configure the sensor in mode
1-4, run CCS811 for 20 minutes, before accurate readings are
generated.
The conditioning period must also be observed before writing
to the BASELINE register.
eCO2
The equivalent CO2 (eCO2) output range for CCS811 is from
400ppm up to 32768ppm.
eTVOC
The equivalent Total Volatile Organic Compound (eTVOC)
output range for CCS811 is from 0ppb up to 32768ppb.
Temperature and Humidity Compensation
If an external sensor is available this information can be written
to CCS811 so that they will be used to compensate gas readings
due to temperature and humidity changes. Refer to the
ENV_DATA (Environment Data) Register (0x05).
Interrupt and Interrupt on Threshold
At the end of each measurement cycle (250ms, 1s, 10s, 60s) a
flag is set and optionally interrupt (nINT) pin asserted. Refer to
the MEAS_MODE (Measurement and Conditions) Register
(0x01). The user can choose to only assert nINT if the eCO2 value
changes into a different range set by register values. Refer to the
THRESHOLDS Register (0x10).
Page 10 ams Datasheet
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CCS811 − Detailed Description
Automatic Baseline Correction
The resistance RS of the sensitive layer is the output of the
sensor. However, metal oxide sensors do not give absolute
readings. The resistance RS varies from sensor to sensor
(manufacturing variation), from use-case to use-case, and over
time. To mitigate this problem, the output of the sensor is
normalized: RS is divided by RA. The value of RA is known as the
baseline. RA cannot be determined by a one-time calibration; it
is maintained on-the-fly in software. This process is known as
baseline correction. The air quality is expected to vary in a
typical environment so the minimum time over which a
baseline correction is applied is 24 hours. Automatic baseline
correction is enabled after initial device operation.
Manual Baseline Correction
There is a mechanism within CCS811 to manually save and
restore a previously saved baseline value using the BASELINE
register.
For additional information on manual baseline control please
refer to application note ams AN000370: CCS811 Clean Air
Baseline Save and Restore.
ams Datasheet Page 11
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CCS811 − Application Information
The recommended application circuit for CCS811 is shown
below.
Figure 8:
Recommended Application Circuit
Note(s):
1. The PWM (Pin 4) and Sense (Pin 5) signals on CCS811 must be connected together.
2. A decoupling capacitor must be placed close to the supply pin VDD on the CCS811.
3. Pull-up resistors for SCL and SDA assumed will be part of host system.
4. If power is not an issue, nWake can be connected to ground if a spare GPIO is not available on the host processor.
5. ADDR must be connected to either VDD (logic 1) or ground (logic 0) depending on the required lsb of the CCS811’s I²C slave address.
Host System Software Requirements
1. The minimum level of driver support that a host system
needs is read and write I²C transactions of data bytes
where the nWAKE pin is asserted at least tAWAKE before
the transaction and kept asserted throughout.
2. An Interrupt handler is also recommended to tell the
application code that the device has asserted an
interrupt.
Application Information
Host
Processor
VDD
4K7
SDA
SCL
VDD
GND
CCS811
Digital VOC sensor
4K7
Part of host
system
4.7uF
GPIOx
SDA
ADDR
SCL
nWAKE
PWM
Sense
nReset
Reset
4K7
nINT
Interrupt
4K7
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CCS811 − Application Information
I²C Interface
I²C transactions require a register address to be selected
(written) and followed by data, as described by the transaction
types in the subsections below. Each Register location
corresponds to a byte or multiple bytes. Multiple reads or writes
in a single sequence will be to or from the same location (the
address does not increment). Therefore, registers are
sometimes referred to as mailboxes in this document.
CCS811 requires the host processor supports clock stretching.
I²C Register Write
Figure 9:
I²C Register Write
As shown above, a transaction may be:
•Single Byte to select a register address for subsequent
read
•Two Bytes to select a register address and write a byte to
it, typically to set a single-byte register value
•Multi-Bytes to select a register address and write several
bytes to it, typically to set multiple configuration bytes
SL AV E ADD RES SS W A DATA(REG ADDR)
DATA
A P
SL AV E ADD RES SS W A DATA(REG ADDR) A
PSL AV E ADD RES SS W A DATA(REG ADDR) A
P
A
A
ADATA
DATA
Write, register address only
Write value to register
Write multiple data
values to register
(mailbox)
From master to slave
From slave to master
SStart condition
PSTOP condition
W
R
Write
Read
AAcknowledge
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CCS811 − Application Information
I²C Register Read
Figure 10:
I²C Register Read
•Since no register address can be supplied during an I²C
read, an I²C write needs to be prepended to select the
required register first.
•The write and read operations can optionally be combined
into a single transaction using a repeated start condition,
as shown in the second example above.
•Select and repeatedly read multiple data values from
register, if the three reads are from the same register
(mailbox), or from three subsequent registers (mailboxes).
SL AV E ADD RES SS W A DATA(REG ADDR) A P
SL AV E ADD RES SS R A PNDATA
Select and read register
value
Select and repeatedly
read multiple data
values from register
(select register address)
(read register value)
Select and read register
value, as single
transaction
SL AV E ADD RES SS W A DATA(REG ADDR) A S SLAVE ADD RES S R A PNDATA
SL AV E ADD RES SS W A DATA(REG ADDR) A P (select register address)
(select register address) (read register value)
SL AV E ADD RES SS R A P
A
DATA NDATA
(read register multiple data)
SL AV E ADD RES SS R A P
A
DATA NDATA (read register multiple data)
SL AV E ADD RES SS R A P
A
DATA NDATA (read register multiple data)
From master to slave
From slave to master
SStart condition
PSTOP condition
W
R
Write
Read
A
N
Acknowledge
Not acknowledge
Page 14 ams Datasheet
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CCS811 − Application Register Overview
All I²C transactions must use the (7 bits) slave address 0x5A or
0x5B depending on status of ADDR pin when writing to and
reading from the CCS811. Figure 11 shows the register map for
CCS811. Figure 22 shows the bootloader register map.
Figure 11:
CCS811 Application Register Map
Note(s):
1. The number of bytes read from a register must not exceed the size in this table.
2. For more information on CCS811 programming requirements please refer to ams application note AN000369.
Address Register R/W Size Description
0x00 STATUS R 1 byte Status register
0x01 MEAS_MODE R/W 1 byte Measurement mode and conditions register
0x02 ALG_RESULT_DATA R up to
8 bytes
Algorithm result. The most significant 2 bytes contain a
ppm estimate of the equivalent CO2 (eCO2) level, and
the next two bytes contain a ppb estimate of the total
VOC level.
0x03 RAW_DATA R 2 bytes Raw ADC data values for resistance and current source
used.
0x05 ENV_DATA W 4 bytes Temperature and humidity data can be written to
enable compensation
0x10 THRESHOLDS W 4 bytes Thresholds for operation when interrupts are only
generated when eCO2 ppm crosses a threshold
0x11 BASELINE R/W 2 bytes The encoded current baseline value can be read. A
previously saved encoded baseline can be written.
0x20 HW_ID R 1 byte Hardware ID. The value is 0x81
0x21 HW Version R 1 byte Hardware Version. The value is 0x1X
0x23 FW_Boot_Version R 2 bytes Firmware Boot Version. The first 2 bytes contain the
firmware version number for the boot code.
0x24 FW_App_Version R 2 bytes Firmware Application Version. The first 2 bytes contain
the firmware version number for the application code
0xA0 Internal_State R 1 byte Internal Status register
0xE0 ERROR_ID R 1 byte Error ID. When the status register reports an error its
source is located in this register
0xFF SW_RESET W 4 bytes
If the correct 4 bytes (0x11 0xE5 0x72 0x8A) are written
to this register in a single sequence the device will reset
and return to BOOT mode.
Application Register Overview
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CCS811 − Application Register Overview
STATUS Register (0x00)
Single byte read only register which indicates if a device is
active, if new data is available or if an error occurred.
Figure 12:
Status Register
76 5 4 3210
FW_MODE APP_ERASE APP_VERIFY APP_VALID DATA_READY - ERROR
Bit(s) Field Description
7FW_MODE
0: Firmware is in boot mode, this allows new firmware to be loaded
1: Firmware is in application mode. CCS811 is ready to take ADC measurements
6APP_ERASE
Boot Mode only.
0: No erase completed
1: Application erase operation completed
5 APP_VERIFY
Boot Mode only.
0: No verify completed
1: Application verify operation completed
After issuing a VERIFY command the application software must wait 70ms before
issuing any transactions to CCS811 over the I²C interface
4APP_VALID
0: No application firmware loaded
1: Valid application firmware loaded
3 DATA_READY
0: No new data samples are ready
1: A new data sample is ready in ALG_RESULT_DATA, this bit is cleared when
ALG_RESULT_DATA is read on the I²C interface
2:1 - Reserved
0ERROR
0: No error has occurred
1: There is an error on the I²C or sensor, the ERROR_ID register (0xE0) contains the
error source
Page 16 ams Datasheet
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CCS811 − Application Register Overview
MEAS_MODE (Measurement and Conditions)
Register (0x01)
This is Single byte register, which is used to enable sensor drive
mode and interrupts.
Figure 13:
Measure Mode Register
765 4 3 210
- DRIVE_MODE INTERRUPT THRESH -
Bit(s) Field Description
7 - Reserved – write ‘0’
6:4 DRIVE_MODE
000: Mode 0 – Idle (Measurements are disabled in this mode)
001: Mode 1 – Constant power mode, IAQ measurement every second
010: Mode 2 – Pulse heating mode IAQ measurement every 10 seconds
011: Mode 3 – Low power pulse heating mode IAQ measurement every 60
seconds
100: Mode 4 – Constant power mode, sensor measurement every 250ms
1xx: Reserved modes (For future use)
In mode 4, the ALG_RESULT_DATA is not updated, only RAW_DATA; the processing
must be done on the host system.
A new sample is placed in ALG_RESULT_DATA and RAW_DATA registers and the
DATA_READY bit in the STATUS register is set at the defined measurement interval.
3INT_DATARDY
0: Interrupt generation is disabled
1: The nINT signal is asserted (driven low) when a new sample is ready in
ALG_RESULT_DATA. The nINT signal will stop being driven low when
ALG_RESULT_DATA is read on the I²C interface.
At the end of each measurement cycle (250ms, 1s, 10s, 60s) a flag is set in the
STATUS register regardless of the setting of this bit..
2INT_THRESH
0: Interrupt mode (if enabled) operates normally
1: Interrupt mode (if enabled) only asserts the nINT signal (driven low) if the new
ALG_RESULT_DATA crosses one of the thresholds set in the THRESHOLDS register
by more than the hysteresis value (also in the THRESHOLDS register)
1:0 - Reserved - write 00
ams Datasheet Page 17
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CCS811 − Application Register Overview
ALG_RESULT_DATA (Algorithm Results Data)
Register (0x02)
This multi-byte read only register contains the calculated eCO2
(ppm) and eTVOC (ppb) values followed by the STATUS register,
ERROR_ID register and the RAW_DATA register.
•If only eCO2 is required, only the first 2 bytes need to be
read.
•If eTVOC is required, 4 bytes need to be read.
•In a system where interrupts are not implemented and the
host needs to poll the STATUS register to determine
whether there is new data, an efficient alternative is to
read 5 bytes in a single transaction since that returns eCO2,
eTVOC and the status register.
•Optionally, all 8 bytes could be read in a single transaction,
so that even the error status and the raw data is available.
Figure 14:
Algorithm Results Register Byte Order
RAW_DATA Register (0x03)
Two byte read only register which contains the latest readings
from the sensor.
The most significant 6 bits of the Byte 0 contain the value of the
current through the sensor (0µA to 63A).
The lower 10 bits contain (as computed from the ADC) the
readings of the voltage across the sensor with the selected
current (1023 = 1.65V)
Figure 15:
RAW_DATA Register Byte Order
Byte 0 Byte 1 Byte 2 Byte 3 Byte 4 Byte 5 Byte 6 & 7
eCO
2
High Byte eCO
2
Low Byte eTVOC High
Byte
eTVOC Low
Byte STATUS ERROR_ID See RAW_DATA
Byte 0 Byte 1
7654321076543210
Current Selected 5:0 Raw ADC reading 9:0
Page 18 ams Datasheet
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CCS811 − Application Register Overview
ENV_DATA (Environment Data) Register (0x05)
A multi-byte register that can be written with the current
Humidity and Temperature values if known.
Relative Humidity
Figure 16:
Relative Humidity Fields and Byte Order
Humidity is stored as an unsigned 16 bits in 1/512%RH. The
default value is 50% = 0x64, 0x00. As an example 48.5%
humidity would be 0x61, 0x00.
Temperature
Figure 17:
Temperature Fields and Byte Order
Temperature is stored as an unsigned 16 bits integer in 1/512
degrees; there is an offset: 0 maps to -25°C. The default value is
25°C = 0x64, 0x00. As an example 23.5% temperature would be
0x61, 0x00.
The internal algorithm uses ENV_DATA values (or default values
if not set by the application) to compensate for changes in
relative humidity and ambient temperature.
For temperatures below-25°C the 7-bit temperature field in
Byte 2 above should be set to all zeros.
Byte 0 Byte 1
Humidity High Byte Humidity Low Byte
7654321076543 2 1 0
64 32 1684211/21/41/81/161/321/641/1281/2561/512
Humidity % Humidity % Fraction
Byte 2 Byte 3
Temperature High Byte Temperature Low Byte
76543210 7 6 5 4 3 2 1 0
64 32 16 8 4 2 1 1/2 1/4 1/8 1/16 1/32 1/64 1/128 1/256 1/512
Temperature 25°C Temperature 25°C Fraction
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CCS811 − Application Register Overview
THRESHOLDS Register (0x10)
If ‘interrupt on threshold change’ has been set in the Mode
register (see above), the values in this multi- byte write only
register are used to determine the thresholds.
Figure 18:
Thresholds Register Byte Order
An interrupt is asserted if the eCO2 value moved from the
current range (Low, Medium, or High) into another range by
more than 50ppm.
•Low to Medium Threshold default = 1500ppm = 0x05DC
•Medium to High Threshold default = 2500ppm = 0x09C4
BASELINE Register (0x11)
A two byte read/write register which contains an encoded
version of the current baseline used in Algorithm Calculations.
A previously stored value may be written back to this two byte
register and the Algorithms will use the new value in its
calculations (until it adjusts it as part of its internal Automatic
Baseline Correction). For more information, refer to ams
application note AN000370: CCS811 Clean Air Baseline Save and
Restore.
HW_ID (Hardware identifier) Register (0x20)
Single byte read only register which holds the HW ID which is
0x81 for this family of CCS81x devices.
HW_Version (Hardware Version) Register
(0x21)
Single byte read only register which holds the Hardware Major
and Minor Hardware versions.
The top four bits read major hardware version 1 – identifying
the product as CCS811. The bottom four bits identify any build
variant. The default value is 0x1X.
Byte 0 Byte 1 Byte 2 Byte 3
Low to Medium Threshold Medium to High Threshold
High Byte Low Byte High Byte Low Byte
Page 20 ams Datasheet
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CCS811 − Application Register Overview
FW_Boot_Version (Firmware Bootloader
Version) Register (0x23)
Two byte read only register which contain the version of the
firmware bootloader stored in the CCS811 in the format
Major.Minor.Trivial
Figure 19:
Firmware Bootloader Version Format
FW_App_Version (Firmware Application
Version) Register (0x24)
Two byte read only register which contain the version of the
firmware application stored in the CCS811 in the format
Major.Minor.Trivial
Figure 20:
Firmware Application Version Format
Byte 0 Byte 1
7654321076543210
Major Minor Trivial
Byte 0 Byte 1
7654321076543210
Major Minor Trivial
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CCS811 − Application Register Overview
ERROR_ID (Error Identifier) Register (0xE0)
If the ERR bit [0] of the STATUS Register is set, this single byte
read only register indicates source(s) of the error.
Figure 21:
ERROR_ID Register Codes
Bit ERROR_CODE Description
0 WRITE_REG_INVALID The CCS811 received an I²C write request addressed to this station but with
invalid register address ID
1 READ_REG_INVALID The CCS811 received an I²C read request to a mailbox ID that is invalid
2 MEASMODE_INVALID The CCS811 received an I²C request to write an unsupported mode to
MEAS_MODE
3 MAX_RESISTANCE The sensor resistance measurement has reached or exceeded the maximum
range
4 HEATER_FAULT The Heater current in the CCS811 is not in range
5 HEATER_SUPPLY The Heater voltage is not being applied correctly
6-Reserved for Future Use
7-Reserved for Future Use
Page 22 ams Datasheet
Document Feedback [v1-05] 2018-May-01
CCS811 − Application Register Overview
SW_RESET Register (0xFF)
As an alternative to Power-On reset or Hardware Reset a
Software Reset is available.
Asserting the SW_RESET will restart the CCS811 in Boot mode
to enable new application firmware to be downloaded.
To prevent accidental SW_RESET a sequence of four bytes must
be written to this register in a single I²C sequence: 0x11, 0xE5,
0x72, 0x8A.
For details, please refer to application notes
ams AN000369 and ams AN000371.
ams Datasheet Page 23
[v1-05] 2018-May-01 Document Feedback
CCS811 − Bootloader Register Overview
All I²C transactions must use the (7bits) slave address 0x5A or
0x5B depending on status of ADDR pin when writing to and
reading from the CCS811. Figure 22 shows the bootloader
register map for CCS811.
Figure 22:
CCS811 Bootloader Register Map
Note(s):
1. The number of bytes read from a register must not exceed the size in this table.
2. For more information on performing application code download please refer to application note ams AN000371.
Address Register R/W Size Description
0x00 STATUS R 1 byte Status register
0x20 HW_ID R 1 byte Hardware ID. The value is 0x81
0x21 HW Version R 1 byte Hardware Version. The value is 0x1X
0x23 FW_Boot_Version R 2 bytes Firmware Boot Version. The first 2 bytes contain the
firmware version number for the boot code.
0x24 FW_App_Version R 2 bytes Firmware Application Version. The first 2 bytes contain
the firmware version number for the application code.
0xE0 ERROR_ID R 1 byte Error ID. When the status register reports an error it
source is located in this register
0xF1 APP_ERASE W 4 bytes
If the correct 4 bytes (0xE7 0xA7 0xE6 0x09) are written
to this register in a single sequence the device will start
the application erase
0xF2 APP_DATA W 9 bytes Transmit flash code for the bootloader to write to the
application flash code space.
0xF3 APP_VERIFY W - Starts the process of the bootloader checking though
the application to make sure a full image is valid.
0xF4 APP_START W -
Application start. Used to transition the CCS811 state
from boot to application mode, a write with no data is
required. Before performing a write to APP_START the
Status register should be accessed to check if there is a
valid application present.
0xFF SW_RESET W 4 bytes
If the correct 4 bytes (0x11 0xE5 0x72 0x8A) are written
to this register in a single sequence the device will reset
and return to BOOT mode.
Bootloader Register Overview
Page 24 ams Datasheet
Document Feedback [v1-05] 2018-May-01
CCS811 − Bootloader Register Overview
Registers not detailed below are documented in the
Application Register Overview section.
APP_ERASE (Application Erase) Register (0xF1)
To prevent accidental APP_ERASE a sequence of four bytes must
be written to this register in a single I²C sequence: 0xE7, 0xA7,
0xE6, 0x09.
The APP_ERASE can take a variable amount of time. The status
register can be polled to determine when this function is
complete. The 6th bit (0x40) is initialised to 0 and set to a 1 on
completion of the APP_ERASE function. After an erase this bit
is only cleared by doing a reset or starting the application.
APP_DATA (Application Data) Register (0xF2)
Nine byte, write only register for sending small chunks of
application data which will be written in order to the CCS811
flash code.
APP_VERIFY (Application Verify) Register
(0xF3)
Single byte write only register which starts the application
verify process run by the bootloader to check for a complete
application code image. Command only needs to be called once
after a firmware download as the result is saved in a flash
location that gets checked during device initialisation.
The APP_VERIFY can take a variable amount of time. The status
register can be polled to determine when this function is
complete. The 5th bit (0x20) is initialised to 0 and set to a 1 on
completion of the APP_VERIFY function. After an APP_VERIFY
this bit is only cleared by doing a reset or starting the
application.
For details on downloading new application firmware please
refer to application note ams AN000371.
APP_START (Application Start) Register (0xF4)
To change the mode of the CCS811 from Boot mode to running
the application, a single byte write of 0xF4 is required.
The CCS811 interprets this as an address write to select the
‘APP_START’ register and starts running the loaded application
software if it is a valid version (Refer to the STATUS Register
(0x00)).
ams Datasheet Page 25
[v1-05] 2018-May-01 Document Feedback
CCS811 − Package Drawings & Marking
LGA Package Outline
Figure 23:
LGA Package Drawings
Note(s):
1. All dimensions are in millimeters.
Package Drawings & Marking
E
D
Pin 1 Corner
Index Area
A
Pin 1 Corner
Index Area
(Top View) (Side View)
D1
E1
e
1.2
2.4
n x W
n x L
(0.3)
(Bottom View)
1
5
10
6
Symbol
Dimensions
Min
Nominal
Max
Total thickness
A
-
-
1.1
Body Size
D
4.0
BSC
E
2.7
BSC
Lead Width
W
0.25
0.3
0.35
Lead Length
L
0.45
0.5
0.55
Lead Pitch
e
0.6
BSC
Lead Count
n
10
Edge Lead Cent
re to Centre
D1
2.4
BSC
E1
2.2
BSC
Green
RoHS
Page 26 ams Datasheet
Document Feedback [v1-05] 2018-May-01
CCS811 − Pack age Drawin gs & Mar king
The recommended package footprint or landing pattern for
CCS811 is shown below:
Figure 24:
Recommended Package Footprint for CCS811
Note(s):
1. All dimensions are in millimeters.
2. PCB land pattern in Green dash lines
3. Pin numbers are in Red
4. Add 0.05mm all around the nominal lead width and length for the PCB land pattern
4
0.6
1.3
0.6
2.7
0.4
0.4
5
1
6
10
(Top View)
0.75
0.7
0.3
0.3
ams Datasheet Page 27
[v1-05] 2018-May-01 Document Feedback
CCS811 − Ordering & Contact Information
Figure 25:
Ordering Information
Note(s):
1. Refer to JEDEC J-STD020 lead-free standard for typical soldering reflow profile
Technical Support is available at:
www.ams.com/Technical-Support
Provide feedback about this document at:
www.ams.com/Document-Feedback
For further information and requests, e-mail us at:
ams_sales@ams.com
For sales offices, distributors and representatives, please visit:
www.ams.com/contact
Headquarters
ams AG
Tobelbader Strasse 30
8141 Premstaetten
Austria, Europe
Tel: +43 (0) 3136 500 0
Website: www.ams.com
Ordering Code Description Package MOQ
CCS811B-JOPR5K CCS811 digital gas sensor for Indoor
Air Quality Monitoring 2.7mm x 4.0mm x 1.1mm LGA 5000
CCS811B-JOPD500 CCS811 digital gas sensor for Indoor
Air Quality Monitoring 2.7mm x 4.0mm x 1.1mm LGA 500
Ordering & Contact Information
Page 28 ams Datasheet
Document Feedback [v1-05] 2018-May-01
CCS811 − RoHS Compliant & ams Green Statement
RoHS: The term RoHS compliant means that ams AG products
fully comply with current RoHS directives. Our semiconductor
products do not contain any chemicals for all 6 substance
categories, including the requirement that lead not exceed
0.1% by weight in homogeneous materials. Where designed to
be soldered at high temperatures, RoHS compliant products are
suitable for use in specified lead-free processes.
ams Green (RoHS compliant and no Sb/Br): ams Green
defines that in addition to RoHS compliance, our products are
free of Bromine (Br) and Antimony (Sb) based flame retardants
(Br or Sb do not exceed 0.1% by weight in homogeneous
material).
Important Information: The information provided in this
statement represents ams AG knowledge and belief as of the
date that it is provided. ams AG bases its knowledge and belief
on information provided by third parties, and makes no
representation or warranty as to the accuracy of such
information. Efforts are underway to better integrate
information from third parties. ams AG has taken and continues
to take reasonable steps to provide representative and accurate
information but may not have conducted destructive testing or
chemical analysis on incoming materials and chemicals. ams AG
and ams AG suppliers consider certain information to be
proprietary, and thus CAS numbers and other limited
information may not be available for release.
RoHS Compliant & ams Green
Statement
ams Datasheet Page 29
[v1-05] 2018-May-01 Document Feedback
CCS811 − Copyrights & Disclaimer
Copyright ams AG, Tobelbader Strasse 30, 8141 Premstaetten,
Austria-Europe. Trademarks Registered. All rights reserved. The
material herein may not be reproduced, adapted, merged,
translated, stored, or used without the prior written consent of
the copyright owner.
Devices sold by ams AG are covered by the warranty and patent
indemnification provisions appearing in its General Terms of
Trade. ams AG makes no warranty, express, statutory, implied,
or by description regarding the information set forth herein.
ams AG reserves the right to change specifications and prices
at any time and without notice. Therefore, prior to designing
this product into a system, it is necessary to check with ams AG
for current information. This product is intended for use in
commercial applications. Applications requiring extended
temperature range, unusual environmental requirements, or
high reliability applications, such as military, medical
life-support or life-sustaining equipment are specifically not
recommended without additional processing by ams AG for
each application. This product is provided by ams AG “AS IS”
and any express or implied warranties, including, but not
limited to the implied warranties of merchantability and fitness
for a particular purpose are disclaimed.
ams AG shall not be liable to recipient or any third party for any
damages, including but not limited to personal injury, property
damage, loss of profits, loss of use, interruption of business or
indirect, special, incidental or consequential damages, of any
kind, in connection with or arising out of the furnishing,
performance or use of the technical data herein. No obligation
or liability to recipient or any third party shall arise or flow out
of ams AG rendering of technical or other services.
Copyrights & Disclaimer
Page 30 ams Datasheet
Document Feedback [v1-05] 2018-May-01
CCS811 − Document Status
Document Status Product Status Definition
Product Preview Pre-Development
Information in this datasheet is based on product ideas in
the planning phase of development. All specifications are
design goals without any warranty and are subject to
change without notice
Preliminary Datasheet Pre-Production
Information in this datasheet is based on products in the
design, validation or qualification phase of development.
The performance and parameters shown in this document
are preliminary without any warranty and are subject to
change without notice
Datasheet Production
Information in this datasheet is based on products in
ramp-up to full production or full production which
conform to specifications in accordance with the terms of
ams AG standard warranty as given in the General Terms of
Trade
Datasheet (discontinued) Discontinued
Information in this datasheet is based on products which
conform to specifications in accordance with the terms of
ams AG standard warranty as given in the General Terms of
Trade, but these products have been superseded and
should not be used for new designs
Document Status
ams Datasheet Page 31
[v1-05] 2018-May-01 Document Feedback
CCS811 − Revision Information
Note(s):
1. Page and figure numbers for the previous version may differ from page and figure numbers in the current revision.
2. Correction of typographical errors is not explicitly mentioned.
Changes from 1-04 (2018-Mar-09) to current revision 1-05 (2018-May-01) Page
Updated text under General Description 1
Updated Figure 1
(Replaced TVOC with eTVOC) 2
Updated text under Applications 2
Updated Figure 5 5
Updated Figure 6 6
Updated text under Modes of Operation and Early-Life Use (Burn-In)
(Replaced TVOC with eTVOC) 8
Updated text under eCO29
Renamed TVOC to eTVOC and updated text under it 9
Updated Figure 11 14
Updated text under ALG_RESULT_DATA and Figure 14
(Renamed all instances of TVOC to eTVOC) 17
Updated Figure 25 27
Updated Figure 26 32
Revision Information
Page 32 ams Datasheet
Document Feedback [v1-05] 2018-May-01
CCS811 − Appendix
References
Figure 26:
Document Reference
Document Reference Description
ams AN000367 CCS811 Assembly guidelines
ams AN000368 CCS811 Design guidelines
ams AN000369 CCS811 Programming and interfacing guide
ams AN000370 CCS811 Clean air baseline save and restore
ams AN000371 CCS811 Performing a firmware download
ams AN000373 CCS811 Factory test procedure
Appendix
ams Datasheet Page 33
[v1-05] 2018-May-01 Document Feedback
CCS811 − Content Guide
1 General Description
2 Key Benefits & Features
2 Applications
3 Block Diagram
4 Pin Assignment
5Absolute Maximum Ratings
6 Electrical Characteristics
8 Detailed Description
8 Modes of Operation
8 Early-Life Use (Burn-In)
9 Conditioning Period (Run-In)
9eCO2
9eTVOC
9 Temperature and Humidity Compensation
9 Interrupt and Interrupt on Threshold
10 Automatic Baseline Correction
10 Manual Baseline Correction
11 Application Information
11 Host System Software Requirements
12 I²C Interface
12 I²C Register Write
13 I²C Register Read
14 Application Register Overview
15 STATUS Register (0x00)
16 MEAS_MODE (Measurement and Conditions) Register
(0x01)
17 ALG_RESULT_DATA (Algorithm Results Data) Register
(0x02)
17 RAW_DATA Register (0x03)
18 ENV_DATA (Environment Data) Register (0x05)
18 Relative Humidity
19 THRESHOLDS Register (0x10)
19 BASELINE Register (0x11)
19 HW_ID (Hardware identifier) Register (0x20)
19 HW_Version (Hardware Version) Register (0x21)
20 FW_Boot_Version (Firmware Bootloader Version) Regis-
ter (0x23)
20 FW_App_Version (Firmware Application Version) Regis-
ter (0x24)
21 ERROR_ID (Error Identifier) Register (0xE0)
22 SW_RESET Register (0xFF)
23 Bootloader Register Overview
24 APP_ERASE (Application Erase) Register (0xF1)
24 APP_DATA (Application Data) Register (0xF2)
24 APP_VERIFY (Application Verify) Register (0xF3)
24 APP_START (Application Start) Register (0xF4)
25 Package Drawings & Marking
25 LGA Package Outline
Content Guide
