HCS2D-3V
Humidity & Temperature Solution
Enhanced Features


Fully Calibrated & Temperature Compensated

Improved Temperature Accuracy & Range(±0.2℃ for ­20 ~ 60℃)

Extremely Low Current Consumption(13㎂ operating)Enhanced Accuracy of RH% (±2%RH, 14bit )Fast Natural Recovery after Reflow Soldering

Low Current Consumption

SIP(Single-In-line-Package)Enhanced Reliability against Chemical

Product Summary
HCS2D-3V is a Single In-Line Package type of
HCP2D-3V with ready installed V-Core capacitor foreasy and convenient application.
HCS2D-3V is an improved version of HumiChip®,the most advanced and cost effective humidity
and temperature sensing solution for virtually any
type of applications.
Capacitive polymer sensor chip developed andfabricated in-house and CMOS integrated circuitwith EEPROM are integrated into one embedded
system in a reflow solder-able SMD package.

Individually calibrated and tested, HCS2D-3V
performs ±2% from 20% to 80%RH (±4% overentire humidity range), and yet, is simple and readyto use without further calibration or temperaturecompensation.
Designed and manufactured by industry leading
humidity and temperature sensing technology of
SAMYOUNG S&C – field proven in HVAC and Autoindustry for over 15 years, HCS2D-3V offers
another smart sensing solution for excellent
reliability, high accuracy, and cost effective sensing
applications.

Application
Energy Saving HVAC Control

Automobile & Transportation

Air Conditioning, Refrigeration, IAQ monitoring,
Vent Fans, Home Appliances, Humi/Dehumidifiers

Cabin Climate Control, Defogging Control
Condensing Preventive Device …,

Process Control & Instrumentations

Mass Quantity Application

Medical Instruments, Handheld Devices, Weather
Stations, Food Processing, Printers, RFIDs …

OEM custom specification available

www.samyoungsnc.com

1/20

V1.0-2015

Sensor Performance
Temperature (°C)

Relative Humidity (%RH)

Resolution

14 bit (0.01%RH)

Resolution

14 bit (0.01℃)

Accuracy¹±2.0 %RH (Figure 1)*

Accuracy³±0.2 ℃ (Figure 2)

Repeatability±0.2 %RH

Repeatability±0.1 ℃

Hysteresis±1.5 %RH

Response time⁴

10.0 sec ( 63%)

Linearity<2.0 %RH

Operating range- 40 ~ 125 ℃

Response time²

Max 8.0 sec ( 63%)

Operating range

0 ~ 100 %RH (Non-Condensing)Long term drift<0.5 %RH/yr (Normal condition)Long term drift<0.05 ℃/yr (Normal
condition)

1. Accuracies measured at 25℃, 3.3V.
2. Measured at 25℃, 1m/sec airflow
for achieving 63% of step from
10%RH to 90%RH
3.Accuracies measured at 25℃, 3.3V.
4.Min 5.0 sec, Max 20 sec

Typical %RH Accuracy at 25℃
Typical Temperature Accuracy

Dimension

Units : mm (inch)

www.samyoungsnc.com

2/20

V1.0-2015

Electrical Specification

Environmental

Supply Voltage

min 2.1v ~ max 3.3V

Supply Current (IDD)

13µA (typical)

Operating Temperature-40 ~ 125℃

*1. at room temperature

Operating Humidity

0 ~ 100% RH(non condensing)

Pin Connection

Absolute Maximum Rating
Parameter

Min

Max

Supply Voltage(VDD)

-0.3V

4.0V

Storage Temp

-40℃

125℃

Junction Temp

-40℃

125℃

Soldering Information
Standard or IR Solder Reflow.
IPC/JEDEC standard
TP ≤250℃, tP < 10sec, TL<220℃, tL<60sec.
Tp(Peak Temperature), tP(Peak Time),
TL(Critical Zone Temperature),tL(Critical Zone
Time)
Ramp-up/down speed < 6℃/sec*. Chip on Board is 100㎋ capacitor for Vcore. (Figure. 2.1)

Shipping
Package Contents
HCS2D-3V consists of a HCS2D-3V and a V-core
capacitor soldered on the top of a FR4 substrate.
Lead Pins are made of Cu, Sn, P alloy and all parts
are fully RoHS and REACH compliant.

Tray :
Inner Box :Out Box :100 ea500 ea5,000 ea

Ordering Information
OutputAccuracy

VDD

Ordering P/N

D

±2%RH

3.3

HCS2D-3V

I²C

www.samyoungsnc.com

3/20

V1.0-2015

Application Guide
CONTENTS
1. General Information
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8

Preliminary Consideration
Operating Conditions
Heating
Storage and Handling Information
Manual soldering
Material Contents
Traceability Information
Shipping Package

6
6
6
6
6
7
7
7

2. Interface Specification
2.1
Digital Output ( I2C Interface )2.1.1 Power Pads
2.1.2 Serial Clock & Data Pads

888

3. Electrical Specification
3.1
3.2
3.3
3.4

Absolute Maximum Rating
Electrical Specification & Recommended Operating Condition
Output Pad Drive Strength
ESD

9
9
9
9

4. Communicating with HCS2D-3V
4.1
Power-On Sequence
4.2
I2C Compatible Interface
4.2.1 I2C Write
4.2.2 I2C Read
4.2.3 I2C Timing
4.3
Opcode4.4
Data Fetch
4.5
EEPROM
4.6
Configurations
4.6.1 RunBit
4.6.2 Status Register

11
11
12
12
12
14
14
16
17
17
17

5. Revision Historywww.samyoungsnc.com

19

4/20

V1.0-2015

List of Tables and Figures
Tables
Table
Table
Table
Table
Table
Table
Table
Table
Table
Table
Table

1
2
3
4
5
6
7
8
9
10
11

Absolute Maximum Rating
Recommended Operating Conditions
Electrical Characteristics Specifications
Characteristics of the SDA and SCL bus lines
OpcodeHumidity & Temperature Conversion Formula
EEPROM Timings
Commands for configurations
Status Register Details
EEPROM Assignments
EEPROM Config Byte

10
11
11
14
15
17
18
18
18
20
20

Operating Conditions
Typical Application Circuit(I2C)
Power-On Sequence
Address Byte
START and STOP condition
I2C principle sequence
I2C Write procedure
I2C Read procedure
Definition of timing for device on the I2C-bus
I2C Measurement Packet Reads
Example : Temperature and Humidity data fetch
EEPROM communication
EEPROM power controlled by user : Write / Erase
EEPROM power controlled by user : Read
EEPROM power controlled automatically : Write / Erase
EEPROM power controlled automatically : Read

6
8
12
12
12
13
13
13
14
15
16
17
18
18
18
18

Packing Tray
Packing (Box)7
7

FiguresFigureFigureFigureFigureFigureFigureFigureFigureFigureFigureFigureFigureFigureFigureFigureFigure

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16

Drawings
Drawing 1.
Drawing 2.

☞ Demo Kit (EVB01-HCP) is available.
A reference program source code can be downloaded from www.samyoungsnc.com

www.samyoungsnc.com

5/20

V1.0-2015

1. General Information
1.1 Preliminary Consideration
To maximize the performance of HCS2D-3V, it isimportant to plan an appropriate location of thesensor at the design stage. Airflow and proper
exposure to ambient air must be secured for
HCS2D-3V to ensure expected performance.
Airflow holes must NOT be blocked. Any heatgenerating parts near HCS2D-3V will distort theproper measurement of relative humidity andtemperature reading, and either should be avoided
or measures should be taken to prevent heattransfer.

1.2 Operating Conditions
HCS2D-3V's maximum and recommended normal
operating condition is shown in Figure 1. Within theNormal Range, HCS2D-3V performs stably.
Prolonged exposures to conditions outside normal
range, especially at humidity over 90%RH, may
temporarily offset the RH signal up to ±3%RH.
When return to Normal Range, it will gradually
recover back to the calibration state.
Re-Conditioning Procedure in section 1.6 will help
reduce this recovery time. Long term exposure to
extreme conditions may also accelerate aging of thesensor.
1.3

Figure 1

Operating Conditions

HeatingHeat sources such as power electronics,
microcontrollers, and display near the sensor may
affect the accurate measurement. The locationof Sensor near such heat sources should be

avoided by maintaining distance or thermal buffer.
Thin metal pattern, or even better, ‘milling slits’
around the sensor also may help reduce the error.

1.4 Storage and Handling Information
HCS2D-3V contains polymer based capacitive
humidity sensor sensitive to environment, andshould NOT be handled as an ordinary electronic
component.
Chemical vapors at high concentration may
interface with the polymer layers, and coupledwith long exposure time, may cause a shift in bothoffset and sensitivity of the sensor.
Despite the sensor endures the extreme
conditions of -40℃~125℃, 0%RH~100%RH (noncondensing), long term exposure in suchenvironment may also offset the sensor reading.
Hence, once the package is opened, it isrecommended to store in clean environment of
temperature at 5℃~55℃ and humidity at
10%~70%RH.
HCS2D-3V is protected of ESD up to 2000V and
Latch-up in the range of ±150㎃ to ±200㎃ andalso packed in ESD protected shipping material.
Normal ESD precaution is required when handlingin assembly process.
.

1.5 Manual soldering
Contact time must be limited to 5 seconds at up to350˚Cwww.samyoungsnc.com

6/20

V1.0-2015

1.6 Material Contents
HCS2D-3V consists of sensor cell and IC(polymer / glass & silicon substrate) packaged ina surface mountable LCC (Leadless Chip Carrier)
type package. The sensor housing consists of a
PPS (Poly Phenylene Sulfide) cap with epoxy
glob top on a standard FR4 substrate. Pads are

made of Au plated Cu. The device is free of Pb,
Cd and Hg.

RoHS compliant / REACH report available

1.7 Traceability Information
HCS2D-3V is laser marked with product type andlot identification.
The first line denotes the sensor type: I²C output.
Lot identification is printed on the second line with 5

digit alphanumeric code.
Further information about individual sensor iselectronically stored on the chip

1.8 Shipping Package
HCS2D-3V is provided in a tray shipment packaging,sealed into antistatic ESD trays. The drawing of the

packaging tapes with sensor orientation andpacking box dimensions are shown in Drawing

Drawing 1

Drawing 2

Packing Tray : 100ea

Inbox: 500ea (5+1Tray(For Cover) X 100ea)

Dimension: 205 x 200 mm

Dimension: 215 x 210 x 30 mm

Packing (Box)

Outbox: 2,500ea (5 x Inbox 500)
Dimension: 355 x 228 x 233 mm

www.samyoungsnc.com

7/20

V1.0-2015

2. Interface Specification
2.1

2.1.1

Digital Output ( I ²C Interface )Power Pads (2: VDD)HCS2D-3V is capable of operating on wide range ofpower supply voltage from 2.1V to 3.3V.
Recommended supply voltage is either 2.1±0.5V or
3.3±0.5V. Power supply should be connected to

2.1.2

VDD (power supply pad 2). VDD and VSS (Groundpad 3) should be decoupled with a 4.7㎌ capacitor.

Serial Clock & Data Pads (1: SCL, 4: SDA)

The sensor’s data is transferred in and out
through the SDA pad while the communication
between HCS2D-3V and microcontroller (MCU) is
synchronized through the SCL pad.
HCS2D-3V has an internal temperaturecompensated oscillator that provide time base forall operation, and uses an I²C-compatible
communication protocol with support up to 100㎑
bit rates.

External pull-up resistors are required to pull thedrive signal high, that can be included in I/Ocircuits of microcontroller. (see Figure 3)
If pads (SDA and SCL) are not used, SCL should
be connected to VDD and SDA should beconnected GND.
Further information about timing and communication
between the sensor and microcontroller is explainedin Section 4. Communicating with HCS2D-3VFigure 2 Typical Application Circuit (I2C)

www.samyoungsnc.com

8/20

V1.0-2015

3.

3.1

Electrical Specification

Absolute Maximum Rating

Table 1 shows the Absolute Maximum Ratings for
HCS2D-3V. Exposure to these extreme
conditions for extended period may deteriorate
3.2

Electrical Specification andRecommended Operating Conditions
The operating conditions recommended for
HCS2D-3V are given in Table 2 and the electrical
specification is shown in Table 3.

3.4

the sensor performance and accelerate aging.
Functional operation is not implied at these
conditions.

3.3

Output Pad Drive Strength

Output pad drive strength is 4㎃.

ESD

All pins have an ESD rating of up to 2㎸. The ESD
test follows the Human Body Model with C=150㎊

Table 1and R=330Ω based on IEC61000-4-2

Absolute Maximum Rating
PARAMETERSYMBOL

MIN

MAX

Unit

Supply Voltage (VDD to GND)VSUPPLY

-0.3

4.0

V

Storage Temperature Range

TSTG

-40

125

°C

Junction Temperature

Tj

-40

125

°C

Table 2

Recommended Operating Conditions
PARAMETERSYMBOL

MIN

Supply Voltage

VDD

Ambient Temperature Range

TAMB

External Capacitance between VDD pin and Gnd
Pull-up on SDA and SCL*1

MAX

UNIT

2.1

3.6

V

-40

125

C

CVSUPPLY
RPU

TYP

㎌

10

㏀

1

*1 : The SDA and SCL should not be left in the open state.
*2 : For the capacitor, the X7R or C0G is recommended.

www.samyoungsnc.com

9/20

V1.0-2015

Table 3

Electrical Characteristics Specifications

PARAMETER
Supply Current
Digital port voltage

SYMBOLIDD
VIO_DIGITAL

Digital ports switching level
Start-Up-Time ,Power-on (POR) to data ready

REMARKSMIN

At 3V, 1Hz

TYP

MAX

㎂

13

Relative to ground

-0.6

3.3

HIGH → LOW

0.3*VDD

LOW → HIGH

0.7*VDDtSTA

VDD+0.6
≤ 3.6

V
V

10

Measuring Rate

UNIT

㎳
㎐

5

EEPROM Data Retention
Periodat 95℃ temperature

10

Year

OTP Data Retention Period

at 95℃ temperature

10

Year

www.samyoungsnc.com

10/20

V1.0-2015

4. Communicating with HCS2D-3V

4.1

Power–On Sequence

On system Power-On-Reset, the HCS2D-3V
wakes as an I²C device. After power-on-reset,
start-up-time is required 10ms.
The CDC is triggered by the conversion timer.
After the CDC is completed, the RDC will be

Figure 3

performed sequentially. Then the DSP calculate
and update the humidity and temperature to
Result Register. The measurement rate is 5㎐(200㎳) by conversion timer. See the Figure 4
Power-on Sequence.

Power-On Sequence

4.2 I2C Compatible Interface
The present paragraph outlines the HCS2D-3V
device specific use of the I2C interface. The
external master (HCS2D-3V cannot be master)
begins the communication by creating a start
condition, falling edge on the SDA line while SCL
is HIGH. It stops the communication by a stop
condition, a rising edge on the SDA line while SCK
is high. Data bits are transferred with the risingedge of SCK.

Figure 4

On I2C buses, every slave holds an individual 7-bit
device address (0x28 fixed). This address has
always to be sent as the first byte after the start
condition. The eighth bit indicating the direction of
the following data transfer (Read : 1 and Write : 0).
The address byte is followed by the opcode andeventually the payload. Each byte is followed byan acknowledge bit (0 : when a slaveacknowledges).

Address Byte

www.samyoungsnc.com

Figure 5

11/20

START and STOP condition

V1.0-2015

Figure 6

4.2.1

I2C principle sequence

I2C Write

During write transactions, the master alone sends
data, the addressed slave just sends the acknowledge bit. The master first sends the slave
address plus the write bit. Then it sends the

Figure 7

HCS2D-3V specific opcode including the register
address in the slave. Finally it sends the payload(“Data“).

I2C Write procedure

4.2.2 I2C Read
During read transactions, the direction ofcommunication has to be commuted. Therefore,
the master creates again a start condition and

Figure 8

sends the slave address plus the read bit (insteadof the write bit) to switch into read mode.
Figure 8 shows.

I2C Read procedure

After arrival of the first (or any) data byte, themaster may be either signal Not-Acknowledge or
Acknowledge.
Not-Acknowledge (=N=1) indicate “end ofread“ and “stop sending“ to the slave.

Acknowledge (=A=0) indicate “continue inautomatic address-increment mode” and thus
receive many bytes in a row. As one can see,automatic address increment is particularly usefuland efficient with the I2C interface.

4.2.3 I2C TimingThe
HCS2D-3V
uses
I2C-compatible
communication protocol with support for Max 100㎑ bit rates. See Figure 10 and Table 4.

www.samyoungsnc.com

Note : Please refer to the I2C-bus specification for
Detailed
TimingChart.
And
Reference
Programming Code are available upon request.

12/20

V1.0-2015

Figure 9

Definition of timing for device on the I 2C-bus

Table 4Characteristics of the SDA and SCL bus lines
PARAMETERSYMBOL

MIN

MAX

UNIT

SCL clock frequency*1

fSCL

0

100

㎑

hold time (repeated) START conditiontHD:STA

4.0

LOW period of the SCL clock

tLOW

4.7

HIGH period of the SCL clock

tHIGH

4.0

set-up time for a repeated START conditiontSU:STA

4.7

data hold time*2

tHD:DAT0data set-up time

tSU:DAT250㎲㎱

rise time of both SDA and SCL signals

tr

1000

㎱

Fall time of both SDA and SCL signals

tf

300

㎱

set-up time for STOP conditiontSU:STO4.0㎲

Bus free time between a STOP and START condition

tBUF

4.7

㎲

capacitive load for each bus line

Cb

400

㎊

data valid timetVD:DAT

3.45㎲

data valid acknowledge timetVD:ACK

3.45㎲

1. Overclocking is technically possible but within the sole responsibility of the customer (a license may be necessary)
2. The data hold time that is measured from the falling edge of SCL, applies to data in transmission and the acknowledge.
A device must internally provide a hold time of at least 300 ns for the SDA signal to bridge the undefined region of thefalling edge of SCL.

www.samyoungsnc.com

13/20

V1.0-2015

4.3 Opcode
All commands for write or read to memory or
configuration or result registers may use explicit
addressing or address auto-increment.
Note : Besides the case of reading the result
registers, it is recommended to deactivate theTable 5converter for any communication to configuration
registers or EEPROM. This is done by setting the
RunBit to ‘0’. After the communication process the
RunBIt needs to be set back to ‘1’.For more details,
see the Section 4.7.

OpcodeDescription

BYTE 2BYTE 1BYTE 0

Read Result

0

1

0

0

0

0

0

0

0

Addr <6..0>

Write configuration

1

1

0

0

0

0

0

0

0

Addr <6..0>

Data <7..0>

Write EEPROM

1

1

1

0

0

0

0

0

0

Addr <6..0>

Data <7..0>

Read EEPROM

0

1

1

0

0

0

0

0

0

Addr <6..0>

Erase EEPROM

1

1

1

0

0

0

1

0

0

Addr <6..0>

Power-on Reset*1

1

0

0

0

1

0

0

0

[ Dummy Byte ]1. It takes about 280us until the first(cdc) measurement starts.

4.4

Data Fetch

The Data Fetch (DF) command is used to fetch
data from HCS2D-3V. An I2C Data Fetch command
starts with the 7-bit slave address and the 8th bit
1(Read). The HCS2D-3V as the slave sends an
acknowledgement (ACK) indicating success.
Figure 10

The number of data bytes returned by the HCS2D3V is determined by when the master sends the
NACK and stop condition. Figure 11 shows
examples of fetching three bytes respectively.

I2C Measurement Packet Reads

www.samyoungsnc.com

14/20

V1.0-2015

The data has to be read from Result Register
using the Read Result command in order to fetch
the humidity and temperature. Read Resultcommand consists of 0x40 and 7-bit address. 7-bit
address is 0x00(for temperature) or 0x03(forhumidity). After commands are transferred, 3bytes data is read from HCS2D-3V. First 2-bytes
are humidity or temperature. They are signed
integer, two’s complement fixed- point. The lower

Figure 11

byte is fractional digits and the higher byte is
integer values. Third byte is Checksum. If it isn’t
used, only 2-bytes can be read.
The checksum and output data are calculated as
Table 6.
To read temperature and humidity at a time, dataof 6-Bytes can be fetched from HCS2D-3V after
commands (0x40+0x00) are sent. The first 3-bytes
are temperature and the next 3-bytes are humidity.

Example : Temperature and Humidity data fetchwww.samyoungsnc.com

15/20

V1.0-2015

Table 6

Humidity & Temperature Conversion Formula
Humidity & Temperature Conversion Formula

Humidity Output (%RH)

RES01[15:0] / 256

Temperature Output (°C)

RES00[15:0] / 256

Checksum

RES[23..16] = (RES[15..8] + RES[7:0]) % 256

Note : ’%’ symbol in Checksum Formula means mod operation.

4.5 EEPROM
The EEPROM array contains the calibration
coefficients for gain and offset, etc., and theconfiguration bits for the output modes,
measuring rate, etc.. The HCS2D-3V EEPROM
is arranged as 127 Bytes.
See Section 4.3 for instructions on reading andwriting to the EEPROM via the I2C interface.
When programming the EEPROM, an internal

Figure 12

charge pump voltage is used; therefore a highvoltage supply is not needed.
Only 1’s can be written to the EEPROM.
Therefore, it is necessary to erase the EEPROM
cells before writing new data. EEPROM
communication may use address auto-increment.
In case of “Erase EEPROM“ the incremental write
is achieved by sending additional dummy bytes.

EEPROM communication

It is necessary to wake up the EEPROM before
each write access. Therefore, Enable EEPROM
after clear RunBit. The EEPROM wakeup can bewww.samyoungsnc.com

done explicitly or automatically. It is mandatory totake care of the setup timings, for each individual
byte.

16/20

V1.0-2015

Table 7

EEPROM Timings

SymbolDescription

Typ.

trdsu

Set-up Time for reading

300㎲

trd

Read Time from EEPROM

600㎱

twrsu

Set-up Time for Writing

200㎲

twr

Write Time to EEPROM

6.8㎳

4.6 Configurations

4.6.1 RunBit
step, RunBit should be set to ‘1’ again.
Use the POR command in order to re-start themeasurement after access is completed.

The RunBit enables or disables the front-end andthe DSP. It is indicated in the Status Register bit0.
When the Configuration Register or EEPROM isaccessed, the Runbit should be ‘0’. Then, as a last

Table 8Commands for configurations
Command

CMD1

CMD2

CMD3

Set RunBit

0xC0

0x4D

0x01

Clear RunBit

0xC0

0x4D

0x00

Enable EEPROM

0xC0

0x1C

0xC4

Disable EEPROM

0xC0

0x1C

0x44

4.6.2

Status Register

Address 24 in the Result Register is the Status
Register. The EEPROM state and the RunBit
are displayed in the Status Register.

Table 9For more information, see Section
EEPROM and Section 4.7.1 RunBit.

Status Register Details

Bit#

Name

0

RunBit2:1

Reserved

3

EE_BUSY

7:4

Reserved

www.samyoungsnc.com

Description
Run Bit (0: Disable, 1: Enable)

EEPROM busy

17/20

V1.0-2015

4.6

Figure 13

EEPROM power controlled by user : Write / Erase

Figure 14

EEPROM power controlled by user : Read

Figure 15

EEPROM power controlled automatically : Write / Erase

Figure 16

EEPROM power controlled automatically : Readwww.samyoungsnc.com

18/20

V1.0-2015

5. Revision History
Date

Version

16 SEPTEMBER 2015

1.0

www.samyoungsnc.com

Page(s)Changes
First Release

19/20

V1.0-2015

This publication is the proprietary product of SAMYOUNG S&C and is copyrighted, with all rights reserved. Under the
copyright laws, no part of this publication may be reproduced or transmitted in any form or by any means, electronic ormechanical, for any purpose, in whole or in part, without the express written permission of SAMYOUNG S&C. Express
written permission is also required before a third party may make any use of this publication.

SAMYOUNG S&C Co., Ltd.
150 Sangdaewon-dong, Jungwon-gu,
Seongnam-city, Gyeonggi-do,
KOREA

462-807

Phone:
Fax:
Homepage:E-mail:+ 82 31 741-1830+ 82 31 741-1821
www.samyoungsnc.com
sales@samyoungsnc.com

This Application Guide should be used only for intended and authorized application of
HCS2D-3V.
Please consult with SAMYOUNG S&C for any specific application requirements and for
detailed datasheet.
Copyright 2015ⓒ, SAMYOUNG S&C

www.samyoungsnc.com

20/20

V1.0-2015