TS04 4-Channel Self Calibration Capacitive Touch Sensor SPECIFICATION V3.0 July 2007 Confidential ADSemiconductor ADSemiconductor® TS04 (4-CH Auto Sensitivity Calibration Capacitive Touch Sensor) 1 Specification 1.1 General Feature 4-Channel capacitive sensor with auto sensitivity calibration Parallel output interface Independently adjustable sensitivity with external capacitor Adjustable internal frequency with external resister Embedded high frequency noise elimination circuit Low current consumption RoHS compliant 16QFN, 14SOP package 1.2 Application Mobile application (mobile phone / PDA / PMP / MP3 etc) Membrane switch replacement Sealed control panels, keypads Door key-lock matrix application 1.3 Package (16 QFN / 14SOP) 16 QFN 14SOP Drawings not to scale ADSemiconductor Confidential 1 /17 ADSemiconductor® TS04 (4-CH Auto Sensitivity Calibration Capacitive Touch Sensor) 2 Pin Description 2.1 16 QFN package PIN No. Name I/O 1 N.C. - 2 RBIAS Analog Input 3 GND - 4 CS1 5 Description Not connect Protection - Internal bias adjust input VDD/GND Connect to GND VDD/GND Analog Input CH1 capacitive sensor input VDD/GND CS2 Analog Input CH2 capacitive sensor input VDD/GND 6 CS3 Analog Input CH3 capacitive sensor input VDD/GND 7 Dummy Analog Input Internal noise monitoring input Do not connect to anywhere VDD/GND 8 GND Ground 9 CS4 Analog Input CH4 capacitive sensor input VDD/GND 10 OUT1 Digital Output Output1 for CS1 (Open Drain structure) VDD/GND 11 OUT2 Digital Output Output2 for CS2 (Open Drain structure) VDD/GND 12 GND Ground 13 OUT3 Digital Output Output3 for CS3 (Open Drain structure) VDD/GND 14 OUT4 Digital Output Output4 for CS4 (Open Drain structure) VDD/GND 15 GND - Connect to GND VDD/GND 16 VDD Power Supply ground VDD Supply ground VDD Power (2.5V~5.0V) GND ADSemiconductor Confidential 2 /17 ADSemiconductor® TS04 (4-CH Auto Sensitivity Calibration Capacitive Touch Sensor) 2.2 14 SOP PIN No. Name I/O Description 1 GND - 2 VDD Power 3 RBIAS Analog Input Internal bias adjust input VDD/GND 4 CS1 Analog Input CH1 capacitive sensor input VDD/GND 5 CS2 Analog Input CH2 capacitive sensor input VDD/GND 6 CS3 Analog Input CH3 capacitive sensor input VDD/GND 7 Dummy Analog Input Internal noise monitoring input Do not connect to anywhere VDD/GND 8 GND Ground 9 CS4 Analog Input CH4 capacitive sensor input VDD/GND 10 OUT1 Digital Output Output1 for CS1 (Open Drain structure) VDD/GND 11 OUT2 Digital Output Output2 for CS2 (Open Drain structure) VDD/GND 12 GND Ground 13 OUT3 Digital Output Output3 for CS3 (Open Drain structure) VDD/GND 14 OUT4 Digital Output Output4 for CS4 (Open Drain structure) VDD/GND Connect to GND Protection VDD/GND Power (2.5V~5.0V) GND Supply ground VDD Supply ground VDD ADSemiconductor Confidential 3 /17 ADSemiconductor® TS04 (4-CH Auto Sensitivity Calibration Capacitive Touch Sensor) 3 Absolute Maximum Rating Battery supply voltage 5.0V Maximum voltage on any pin VDD+0.3 Maximum current on any PAD 100mA Power Dissipation 800mW Storage Temperature -50 ~ 150℃ Operating Temperature -20 ~ 75℃ Junction Temperature 150℃ Note Unless any other command is noted, all above are operated in normal temperature. 4 ESD & Latch-up Characteristics 4.1 ESD Characteristics Mode H.B.M M.M Polarity Pos / Neg Pos / Neg Minimum Level Reference 5000V VDD 3000V VSS 5000V P to P 500V VDD 300V VSS 500V P to P 500V C.D.M Pos / Neg DIRECT 800V 4.2 Latch-up Characteristics Mode Polarity Minimum Level Positive 200mA Negative -200mA Positive 8.0V I Test V supply over 5.0V Test Step 25mA 1.0V ADSemiconductor Confidential 4 /17 ADSemiconductor® TS04 (4-CH Auto Sensitivity Calibration Capacitive Touch Sensor) 5 Electrical Characteristics ▪ VDD=3.3V, Rb=510k, Sync Mode (Rsync = 2MΩ) (Unless otherwise noted), TA = 25℃ Characteristics Symbol Operating supply voltage VDD Current consumption IDD Digital output maximum sink current IOUT Internal reset criterion VDD voltage VDD_RST Sense input capacitance range [Note1] CS Minimum detective capacitance difference ΔC Output impedance (open drain) ZO Self calibration time after system reset TCAL Sense input resistance range RS Recommended bias resistance range [Note2] RB Test Condition Min Typ Max Units 2.5 3.3 5.0 V VDD= 3.3V RB=510k RSB=0 - 40 70 VDD= 5.0V RB=510k RSB =0 - 80 140 TA = 25℃ (Normal I2C Output) - - 4.0 ㎃ - - 0.3∙VDD V - - 100 ㎊ 0.2 - - ㎊ ΔC > 0.2pF, Cs = 10pF - 12 - ΔC < 0.2pF, Cs = 10pF - 30M - VDD = 3.3V RB = 510k - 100 - VDD = 5.0V RB = 510k - 80 - - 200 1000 VDD = 3.3V 200 510 820 VDD = 5.0V 330 620 1200 TA = 25℃, RB=510k Cs = 10pF ㎂ Ω ms Ω kΩ Note 1 : The sensitivity can be increased with lower CS value. The recommended value of CS is 10pF when using 3T PC(Poly Carbonate) cover and 10 ㎜ x 7 ㎜ touch pattern. Note 2 : The lower RB is recommended in noisy condition. ADSemiconductor Confidential 5 /17 ADSemiconductor® TS04 (4-CH Auto Sensitivity Calibration Capacitive Touch Sensor) 6 Implementation of TS04 6.1 RBIAS & SRBIAS implementation RBIAS << RB The RBIAS is connected the resistor to decide the oscillator and internal bias current. The sensing frequency, internal clock frequency and current consumption are therefore able to be adjusted with RB. IDD [uA] 180.0 2.5 V 160.0 3.3 V 140.0 5.0 V 120.0 100.0 80.0 60.0 40.0 20.0 0.0 100 200 300 400 500 600 RB [kΩ] 700 800 900 1000 1100 Normal operation current consumption curve The current consumption curve of TS04 is represented in accordance with RB value as above. The lower RB requires more current consumption but it is recommended in noisy application. For example, refrigerator, air conditioner and so on. ADSemiconductor Confidential 6 /17 ADSemiconductor® TS04 (4-CH Auto Sensitivity Calibration Capacitive Touch Sensor) 6.2 CS implementation RS4 CS4 << Touch PAD4 CS4 RS1 CS1 << Touch PAD1 CS1 The TS04 has available sensing channel up to 4. The parallel capacitor CS1 is added to CS1 and CS4 to CS4 to adjust fine sensitivity. The sensitivity would increase when a smaller value of CS is used. (Refer to the below Sensitivity Example Figure) It could be useful in case detail sensitivity mediation is required. The internal touch decision process of each channel is separated from each other. The four channel touch key board application can therefore be designed by using only one TS04 without coupling problem. The RS is serial connection resistor to avoid malfunction from external surge and ESD. (It might be optional.) From 200Ω to 1kΩ is recommended for RS. The size and shape of PAD might have influence on the sensitivity. The sensitivity will be optimal when the size of PAD is approximately an half of the first knuckle (it’s about 10 ㎜ｘ 7 ㎜). The connection line of CS1 ~ CS4 to touch PAD is recommended to be routed as short as possible to prevent from abnormal touch detect caused by connection line. There are some sensitivity difference among CS1, CS2 and CS3, and CS4 caused by internal parasitic capacitance. That sensitivity difference could be compensated by using different CS capacitor or sensitivity setting with internal register. To use different touch pattern area could be used for sensitivity compensation but not recommended. The sensitivity of each channel can be represented as below. Sensitivity of CS1 ≥ Sensitivity of CS2, CS3 > Sensitivity of CS4 (In case of the external parasitic capacitance value is same on each channel.) CCS1_PARA + about 3.5pF = CCS2,3_PARA + about 3pF = CCS4_PARA * CCS1_PARA : Parasitic capacitance of CS1 * CCS2,3_PARA : Parasitic capacitance of CS2 and CS3 * CCS4_PARA : Parasitic capacitance of CS4 ADSemiconductor Confidential 7 /17 ADSemiconductor® TS04 (4-CH Auto Sensitivity Calibration Capacitive Touch Sensor) Sensitivity example figure with default sensitivity selection ADSemiconductor Confidential 8 /17 ADSemiconductor® TS04 (4-CH Auto Sensitivity Calibration Capacitive Touch Sensor) 6.3 Output Circuit Implementation VDD ROUT1 OUT1 OUTPUT1 ROUT2 ROUT3 OUTPUT2 OUT2 ROUT4 OUTPUT3 OUT3 OUTPUT4 OUT4 The OUTPUT pins have an open drain structure. For this reason, the connection of pull-up resistor ROUT is required between OUTPUT and VDD. The maximum output sink current is 4mA, so over a few kΩ must be used as ROUT. Normally 10kΩ is used as ROUT. The OUTPUT is high in normal situation, and the value is low when a touch is detected on the corresponding CS. 6.4 Internal reset operation The TS04 has stable internal reset circuit to offer reset pulse to digital block. The supply voltage for a system start or restart should be under 0.3∙VDD of normal operation VDD. No external components required for TS04 power reset, that helps simple circuit design and to realize the low cost application. ADSemiconductor Confidential 9 /17 ADSemiconductor® TS04 (4-CH Auto Sensitivity Calibration Capacitive Touch Sensor) 7 Recommended Circuit Diagram 7.1 Application Example (16QFN) TS04(16QFN) Application Example Circuit In PCB layout, RB should not be placed on touch pattern. The RB pattern should be routed as short as possible. The CS patterns also should be routed as short as possible and the width of line might be about 0.25mm (or narrower line). The capacitor that is between VDD and GND is an obligation. It should be located as close as possible from TS04. The CS pattern routing should be formed by bottom metal (opposite metal of touch PAD). The empty space of PCB must be filled with GND pattern to strengthen GND pattern and to prevent external noise from interfere with sensing frequency. The TS04 is reset when power rise from 0V to proper VDD ADSemiconductor Confidential 10 /17 ADSemiconductor® TS04 (4-CH Auto Sensitivity Calibration Capacitive Touch Sensor) The VDD periodic voltage ripple over 50mV and the ripple frequency is lower than 10 kHz can cause wrong sensitivity calibration. To prevent above problem, power (VDD, GND) line of touch circuit should be separated from other circuit. Especially LED driver power line or digital switching circuit power line certainly should be treated to be separated from touch circuit. The smaller R_B is recommended in noisy environments. About 200Ω Resistor (RS1~RS4) and parallel capacitor (CS1~CS4) is might be inserted to improve external noise immunity. Parallel capacitor value effects on touch sensitivity. The LED_GND and GND should be short in the system and the lines are recommended to be split from the most low impedance ground point to avoid ground bouncing problems. 7.2 Application Example (14 SOP) TS04(14 SOP) Application Example Circuit ADSemiconductor Confidential 11 /17 ADSemiconductor® TS04 (4-CH Auto Sensitivity Calibration Capacitive Touch Sensor) 7.3 Example – Power Line Split Strategy PCB Layout A. Not split power line (Bad power line design) The noise that is generated by AC load or relay can be loaded at 5V power line. A big inductance might be appeared in case of the connection line between main board and display board is too long, moreover the voltage ripple could be generated by LED (LCD) display driver at VDD (5V). B. Split power line (One 5V regulator used) – Recommended C. Split power line (Separated 5V regulator used) – Strongly recommended ADSemiconductor Confidential 12 /17 ADSemiconductor® TS04 (4-CH Auto Sensitivity Calibration Capacitive Touch Sensor) 8 MECHANICAL DRAWING 8.1 Mechanical drawing (16 QFN) NOTE: Dimensions are in millimeters ADSemiconductor Confidential 13 /17 ADSemiconductor® TS04 (4-CH Auto Sensitivity Calibration Capacitive Touch Sensor) ADSemiconductor Confidential 14 /17 ADSemiconductor® TS04 (4-CH Auto Sensitivity Calibration Capacitive Touch Sensor) 8.2 Mechanical Drawing (14 SOP) ADSemiconductor Confidential 15 /17 ADSemiconductor® TS04 (4-CH Auto Sensitivity Calibration Capacitive Touch Sensor) 9 MARKING DESCRIPTION Device Code : TS04 Channel Number Touch Switch Group Weekly Code : YY WW Manufacturing Year Manufacturing Week ADSemiconductor Confidential 16 /17 ADSemiconductor® TS04 (4-CH Auto Sensitivity Calibration Capacitive Touch Sensor) NOTES: LIFE SUPPORT POLICY AD SEMICONDUCTOR’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF AD SEMICONDUCTOR CORPORATION The ADS logo is a registered trademark of ADSemiconductor ⓒ 2006 ADSemiconductor – All Rights Reserved www.adsemicon.com www.adsemicon.co.kr ADSemiconductor Confidential 17 /17