PCF8883_11

PCF8883 Capacitive proximity switch with auto-calibration, large voltage operating range and very low power consumption Rev. 2 — 8 March 2011 Product data sheet 1. General description The integrated circuit PCF8883 is a capacitive proximity switch that uses a patented (EDISEN) digital method to detect a change in capacitance on a remote sensing plate. Changes in the static capacitance (as opposed to dynamic capacitance changes) are automatically compensated using continuous auto-calibration. Remote sensing plates (e.g. conductive foil) can be connected directly to the IC1 or remotely using a coaxial cable. 2. Features and benefits Dynamic proximity switch Digital processing method Adjustable sensitivity, can be made very high Adjustable response time Wide input capacitance range (10 pF to 60 pF) Automatic calibration A large distance (several meters) between the sensing plate and the IC is possible Open-drain output (P-type MOSFET, external load between pin and ground) Designed for battery powered applications (IDD = 3 μA, typical) Output configurable as push-button, toggle, or pulse Wide voltage operating range (VDD = 3 V to 9 V) Large temperature operating range (Tamb = −40 °C to +85 °C) Internal voltage regulator Available in SOIC8 (other packages available on request for larger quantities) 1. The definition of the abbreviations and acronyms used in this data sheet can be found in Section 16. NXP Semiconductors PCF8883 Capacitive proximity switch with auto-calibration 3. Applications Proximity detection Proximity sensing in Mobile phones Portable entertainment units Switch for medical applications Switch for use in explosive environments Vandal proof switches Transportation: Switches in or under upholstery, leather, handles, mats, and glass Buildings: switch in or under carpets, glass, or tiles Sanitary applications: use of standard metal sanitary parts (e.g. tap) as switch Hermetically sealed keys on a keyboard 4. Ordering information Table 1. Ordering information Package Name PCF8883T/1 SOIC8 Description plastic small outline package; 8 leads; body width 3.9 mm Version PCF8883 Type number 5. Marking Table 2. Marking codes Marking code PCF8883 Type number PCF8883T/1 PCF8883 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved. Product data sheet Rev. 2 — 8 March 2011 2 of 25 NXP Semiconductors PCF8883 Capacitive proximity switch with auto-calibration 6. Block diagram VDD(INTREGD) VDD(INTREGD) Vref fs & VOLTAGEREGULATOR VDD VDD(INTREGD) CUP COUNTER LOGIC CDN & PCF8883 IN (1) OUT OSCILLATOR Isink fs TYPE VSS CPC CLIN 013aaa072 (1) 150 nA. Fig 1. Block diagram of PCF8883 PCF8883 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved. Product data sheet Rev. 2 — 8 March 2011 3 of 25 NXP Semiconductors PCF8883 Capacitive proximity switch with auto-calibration 7. Pinning information 7.1 Pinning IN TYPE CPC VSS 1 2 8 7 VDD(INTREGD) CLIN OUT VDD PCF8883 3 4 6 5 013aaa073 Top view. For mechanical details, see Figure 16. Fig 2. Pin configuration of PCF8883 (SOIC8) 7.2 Pin description Table 3. Symbol IN TYPE CPC VSS VDD OUT CLIN VDD(INTREGD) Pin description Pin 1 2 3 4 5 6 7 8 Description sensor input pin OUT behavior configuration input sensitivity setting ground supply voltage supply voltage switch output sampling rate setting internal regulated supply voltage output PCF8883 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved. Product data sheet Rev. 2 — 8 March 2011 4 of 25 NXP Semiconductors PCF8883 Capacitive proximity switch with auto-calibration 8. Functional description Figure 3 and Figure 4 show the functional principle of the PCF8883. The discharge time (tdch) of a chip-internal RC timing circuit, to which the external sensing plate is connected via pin IN, is compared to the discharge time (tdch(ref)) of a second chip-internal reference RC timing circuit. Both RC timing circuits are periodically charged from VDD(INTREGD) via identical switches and then discharged via a resistor to ground (VSS). Both switches are synchronized. VDD(INTREGD) Vref fs & VDD(INTREGD) CUP COUNTER LOGIC CDN & IN Isink VSS CPC 013aaa093 Fig 3. Functional diagram of the sensor logic The charge-discharge cycle is governed by the sampling rate (fs). If the voltage of one of the RC timing circuits falls below the internal reference voltage Vref, the respective comparator output will become LOW. The logic following the comparators determines which comparator switches first. If the upper (reference) comparator switches then a pulse is given on CUP. If the lower (input) comparator switches first then a pulse is given on CDN (see Figure 3). The pulses control the charge on the external capacitor CCPC on pin CPC. Every time a pulse is given on CUP, capacitor CCPC is charged from VDD(INTREGD) for a fixed time causing the voltage on CCPC to rise. Likewise when a pulse occurs on CDN, capacitor CCPC is connected to a current sink to ground for a fixed time causing the voltage on CCPC to fall. PCF8883 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved. Product data sheet Rev. 2 — 8 March 2011 5 of 25 NXP Semiconductors PCF8883 Capacitive proximity switch with auto-calibration If the capacitance on pin IN increases, the discharge time tdch increases too. Therefore it will take longer for the voltage on the corresponding comparator to drop below Vref. Only once this happens, the comparator output will become LOW and this results in a pulse on CDN discharging the external capacitor CCPC slightly. Thus most pulses will now be given by CUP. Without further action, capacitor CCPC would then fully charge. However, a chip-internal automatic calibration mechanism that is based on a voltage controlled sink current (Isink) connected to pin IN attempts to equalize the discharge time tdch with the internal reference discharge time tdch(ref). The current source is controlled by the voltage on CCPC which causes the capacitance on pin IN to be discharged more quickly in the case that the voltage on CCPC is rising, thereby compensating for the increase in capacitance on input pin IN. This arrangement constitutes a closed-loop control system that constantly attempts to equalize the discharge time tdch with tdch(ref). This allows compensating for slow changes in capacitance on input pin IN. Fast changes due to an approaching hand for example will not be compensated. In the equilibrium state the discharge times are equal and the pulses alternate between CUP and CDN. From this also follows that an increase in capacitor value CCPC results in a smaller voltage change per pulse CUP or CDN. Thus the compensation due to internal current sink source Isink is slower and therefore the sensitivity of the sensor will increase. Likewise a decrease in capacitor CCPC will result in a lower sensitivity. (For further information see Section 13.) VDD(INTREGD) VOLTAGE REGULATOR VDD PCF8883 SENSING PLATE COAXIAL CABLE CSENS CCABLE RC CF OSCILLATOR fs TYPE VSS CPC CLIN 013aaa075 SENSOR LOGIC RF IN COUNTER LOGIC OUT CSENS = sensing plate capacitance. CCABLE = cable capacitance. RC = external discharge (pull-down) resistor. RF = low pass filter resistor. CF = low pass filter capacitor. Fig 4. Functional principle of the PCF8883 PCF8883 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved. Product data sheet Rev. 2 — 8 March 2011 6 of 25 NXP Semiconductors PCF8883 Capacitive proximity switch with auto-calibration The counter, following the sensor logic depicted in Figure 3, counts the pulses of CUP or CDN respectively. The counter is reset every time the pulse sequence changes from CUP to CDN or vice versa. Pin OUT will only be activated when a sufficient number of consecutive CUP or CDN pulses occur. Low level interference or slow changes in the input capacitance do not cause the output to switch. Various measures, such as asymmetrical charge and discharge steps, are taken to ensure that the output switches off correctly. A special start-up circuit ensures that the device reaches equilibrium quickly when the supply is attached. Pin OUT is an open-drain output capable of pulling an external load Rext (at maximum current of 20 mA) up to VDD. The load resistor must be dimensioned appropriately, taking the maximum expected VDD voltage into account. The output will be automatically deactivated (short circuit protection) for loads in excess of 30 mA. Pin OUT can also drive a CMOS input without connection of the external load. A small internal 150 nA current sink Isink enables a full voltage swing to take place on OUT, even if no load resistor is connected. This is useful for driving purely capacitive CMOS inputs. The falling slope can be fairly slow in this mode, depending on load capacitance. The sampling rate (fs) corresponds to half of the frequency used in the RC timing circuit. The sampling rate can be adjusted within a specified range by selecting the value of CCLIN. The oscillator frequency is internally modulated by 4 % using a pseudo random signal. This prevents interference caused by local AC-fields. 8.1 Output switching modes The output switching behavior can be selected using pin TYPE (see Figure 5) • Push-button (TYPE connected to VSS): The output OUT is active as long as the capacitive event2 lasts. • Toggle (TYPE connected to VDD(INTREGD)): The output OUT is activated by the first capacitive event and deactivated by a following capacitive event. • Pulse (CTYPE connected between TYPE and VSS): The output OUT is activated for a defined time at each capacitive event. The pulse duration is determined by the value of CTYPE and is approximately 2.5 ms/nF. A typical value for CTYPE is 4.7 nF which results in an output pulse duration of about 10 ms. The maximum value of CTYPE is 470 nF which results in a pulse duration of about 1 s. Capacitive events are ignored that occur during the time the output is active. Figure 5 illustrates the switching behavior for the output switching modes. Additionally the graph illustrates, that short term disturbances on the sensor are suppressed by the circuit. 2. A capacitive event is a dynamic increase of capacitance at the sensor input pin IN. All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved. PCF8883 Product data sheet Rev. 2 — 8 March 2011 7 of 25 NXP Semiconductors PCF8883 Capacitive proximity switch with auto-calibration Capacitance on input t OUT (push-button) t OUT (toggle) t OUT (pulse) tclk(H) = CTYPE · 2 ms/nF tclk(H) = CTYPE · 2 ms/nF tclk(H) = CTYPE · 2 ms/nF t 013aaa077 Fig 5. Switching modes timing diagram of PCF8883 8.2 Voltage regulator The PCF8883 implements a chip-internal voltage regulator supplied by pin VDD that provides an internal supply (VDD(INTREGD)) limited to a maximum of 4.6 V. The lock-in voltage Vlockin on VDD is typically 4.0 V. The regulated supply is available at pin VDD(INTREGD) and can be used to supply power to external electronic components (at a maximum current of 0.5 mA). Figure 6 shows the relationship between VDD and VDD(INTREGD). VDD(max) operational range of PCF8883 VDD VDD(max) Vlockin(max) VDD(INTREGD) Vlockin(min) VDD(min) DVDD 013aaa078 Vlockin(max) VDD(INTREGD) Vlockin(min) VDD(min) Fig 6. Integrated voltage regulator PCF8883 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved. Product data sheet Rev. 2 — 8 March 2011 8 of 25 NXP Semiconductors PCF8883 Capacitive proximity switch with auto-calibration 9. Limiting values Table 4. Limiting values In accordance with the Absolute Maximum Rating System (IEC 60134). Symbol Parameter VDD VI IO ISS II Ptot VESD Ilu Tstg Tamb [1] [2] [3] [4] Conditions on pins IN, TYPE, CPC on pin OUT on any other pin HBM MM [1] [2] [3] [4] Min Max Unit V V mA mA mA mW V V mA °C °C supply voltage input voltage output current ground supply current input current total power dissipation electrostatic discharge voltage latch-up current storage temperature ambient temperature operating device −0.5 +9 −0.5 VDD(INTREGD) + 0.5 −10 −10 −10 −60 −40 +50 +50 +10 100 ±2000 ±200 100 +125 +85 Pass level; Human Body Model (HBM) according to Ref. 6 “JESD22-A114”. Pass level; Machine Model (MM), according to Ref. 7 “JESD22-A115”. Pass level; latch-up testing, according to Ref. 8 “JESD78” at maximum ambient temperature (Tamb(max)). According to the NXP store and transport requirements (see Ref. 10 “NX3-00092”) the devices have to be stored at a temperature of +8 °C to +45 °C and a humidity of 25 % to 75 %. For long term storage products divergent conditions are described in that document. PCF8883 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved. Product data sheet Rev. 2 — 8 March 2011 9 of 25 NXP Semiconductors PCF8883 Capacitive proximity switch with auto-calibration 10. Static characteristics Table 5. Static characteristics VDD = 5 V, Tamb = +25 °C; unless otherwise specified. Symbol VDD Parameter supply voltage Conditions 10 pF ≤ Ci ≤ 40 pF; −40 °C ≤ Tamb ≤ +85 °C 10 pF ≤ Ci ≤ 35 pF; −20 °C ≤ Tamb ≤ +85 °C Vlockin VDD(INTREGD) lock-in voltage internal regulated supply voltage no external load VDD > Vlockin VDD < Vlockin idle state; fs = 1 kHz VDD = 5.0 V VDD = 3.0 V Isink VO IO sink current output voltage output current internal constant current to VSS on pin OUT; pull-up voltage P-MOS short circuit protection VO ≥ 0.6 V Vsat saturation voltage on pin OUT; IO = +10 mA VDD = 5.0 V VDD = 3.0 V Cdec Vi(CPC) [1] [2] [3] [4] [3] [2] [1] Min Typ Max 3.0 2.8 3.0 4.0 4.0 10 9.0 9.0 4.6 50 Unit V V V V mV ΔVDD(INTREGD) internal regulated supply voltage variation IDD supply current 0 0 20 3 2.2 5 3.5 μA μA nA V mA mA 150 VDD 9.0 10 30 20 50 0.1 0.1 [4] 0.2 0.3 - 0.4 0.5 220 V V nF decoupling capacitance input voltage on pin CPC on pin VDD(INTREGD) 100 0.6 VDD(INTREGD) − 0.3 V Alternatively an external discharge resistor RC can be used (see Section 13). Idle state is the steady state after completed power-on without any activity on the sensor plate and the voltage on the reservoir capacitor CCPC settled. For reliability reasons the average output current must be limited to 4.6 mA at 70 °C and 3.0 mA at 85 °C. External ceramic chip capacitor recommended (see Figure 15). PCF8883 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved. Product data sheet Rev. 2 — 8 March 2011 10 of 25 NXP Semiconductors PCF8883 Capacitive proximity switch with auto-calibration 11. Dynamic characteristics Table 6. Dynamic characteristics VDD = 5 V, CCLIN = 22 pF, CCPC = 470 nF, Tamb = +25 °C; unless otherwise specified. Symbol CCLIN CCPC CTYPE Ci Parameter capacitance on pin CLIN capacitance on pin CPC capacitance on pin TYPE input capacitance sensing plate and connecting cable VDD = 5.0 V Tamb = −40 °C to +85 °C; VDD = 3.0 V RDSon tch tdch tstartup tp drain-source on-state resistance charge time discharge time start-up time pulse duration internal pull-up on input per sample per sample until normal operation is established on pin OUT; in pulse mode; CTYPE ≥ 10 nF CCLIN = 0 pF CCLIN = 22 pF (typical value) CCLIN = 100 pF tsw switching time at fs = 1 kHz 10 10 1.4 2.5 1.0 0.5 2.5 60 40 500 3.5 pF pF Ω μs μs s ms/nF X7R ceramic chip capacitor Conditions Min 0 90 0.1 Typ 22 470 14 Max 100 2500 470 Unit pF nF bit nF Nres(dig)eq equivalent digital resolution fs sampling frequency - 3.3 1 275 64 - kHz kHz Hz ms PCF8883 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved. Product data sheet Rev. 2 — 8 March 2011 11 of 25 NXP Semiconductors PCF8883 Capacitive proximity switch with auto-calibration 12. Characteristic curves 12.1 Power consumption 3.5 IDD (μA) 3.0 001aak839 2.5 2.0 2 4 6 8 VDD (V) 10 Idle state; fs = 1 kHz; Tamb = 25 °C. Fig 7. IDD with respect to VDD 4.0 IDD (μA) 3.5 VDD = 9 V 3.0 001aak840 2.5 VDD = 3 V 2.0 1.5 −50 0 50 100 Temperature (°C) Idle state; fs = 1 kHz. Fig 8. IDD with respect to temperature PCF8883 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved. Product data sheet Rev. 2 — 8 March 2011 12 of 25 NXP Semiconductors PCF8883 Capacitive proximity switch with auto-calibration 4.0 IDD (μA) 3.5 001aak841 3.0 2.5 2.0 1.5 250 750 1250 fs (Hz) 1750 Idle state; VDD = 6 V; Tamb = 25 °C. Fig 9. IDD with respect to sampling frequency (fs) 12.2 Typical reaction time 300 tsw (ms) 200 001aak842 100 0 0 500 1000 1500 fs (Hz) 2000 VDD = 6 V; Tamb = 25 °C. Fig 10. Switching time (tsw) with respect to sampling frequency (fs) PCF8883 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved. Product data sheet Rev. 2 — 8 March 2011 13 of 25 NXP Semiconductors PCF8883 Capacitive proximity switch with auto-calibration 250 tsw (ms) 200 001aak843 150 100 50 0 0 40 80 CCLIN (pF) 120 VDD = 6 V; Tamb = 25 °C. Fig 11. Switching time (tsw) with respect to capacitor on pin CLIN (CCLIN) 75 tsw (ms) 70 001aak844 65 60 55 50 −50 0 50 100 Temperature (°C) VDD = 6 V. Fig 12. Switching time (tsw) with respect to temperature PCF8883 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved. Product data sheet Rev. 2 — 8 March 2011 14 of 25 NXP Semiconductors PCF8883 Capacitive proximity switch with auto-calibration 12.3 Reservoir capacitor voltage 3 VI(CPC) (V) 2 001aak845 1 0 0 20 40 CIN (pF) 60 VDD = 6 V; Tamb = 25 °C. Vi(CPC) = input voltage on pin CPC. CIN = capacitor on pin IN. Fig 13. Input voltage on pin CPC (Vi(CPC)) with respect to capacitor on pin IN (CIN) 3.5 VI(CPC) (V) 3.0 CIN = 60.8 pF 001aak846 2.5 CIN = 37 pF 2.0 -50 0 50 100 Temperature (°C) VDD = 6 V. Vi(CPC) = input voltage on pin CPC. Fig 14. Input voltage on pin CPC (Vi(CPC)) with respect to temperature PCF8883 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved. Product data sheet Rev. 2 — 8 March 2011 15 of 25 NXP Semiconductors PCF8883 Capacitive proximity switch with auto-calibration 13. Application information Figure 15 shows the typical connections for a general application3. The positive supply is connected to pin VDD. It is recommended to connect smoothing capacitors to ground to both VDD and VDD(INTREGD) (values for Cdec, see Table 5). SENSING PLATE COAXIAL CABLE CSENS Toggle Pulse RF RC CF IN VDD(INTREGD) VDD(INTREGD) TYPE Pushbutton CLIN PCF8883 CPC OUT VSS VDD 013aaa079 CSENS = sensing plate capacitance. The coaxial cable is optional. Fig 15. Typical application The sampling rate is determined by the capacitance CCLIN on pin CLIN. A higher sampling rate reduces the reaction time and increases the current consumption. The sensing plate capacitance CSENS may consist of a small metal area, for example behind an isolating layer. The sensing plate can be connected to a coaxial cable (CCABLE) which in turn is connected to the input pin IN. Alternatively, the sensing plate can be directly connected to the input pin IN. An internal low pass filter is used to reduce RF interference. An additional low pass filter consisting of a resistor RF and capacitor CF can be added to the input to further improve RF immunity as required. For good performance, the total amount of capacitance on the input (CSENS + CCABLE + CF) should be in the proper range, the optimum point being around 30 pF. These conditions allow the control loop to adapt to the static capacitance on CSENS and to compensate for slow changes in the sensing plate capacitance. A higher capacitive input loading is possible provided that an additional discharge resistor RC is placed as shown in Figure 15. Resistor RC simply reduces the discharge time such that the internal timing requirements are fulfilled. The sensitivity of the sensor can be influenced by the sensing plate area and capacitor CCPC. The sensitivity is significantly reduced when CCPC is reduced. When maximum sensitivity is desired CCPC can be increased, but this also increases sensitivity to 3. For further information see Ref. 2 “AN10832”. Information about the appropriate evaluation board can be found in Ref. 11 “UM10370”. All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved. PCF8883 Product data sheet Rev. 2 — 8 March 2011 16 of 25 NXP Semiconductors PCF8883 Capacitive proximity switch with auto-calibration interference. Pin CPC has a high-impedance and is sensitive to leakage currents. Therefore CCPC should be a high quality foil or ceramic capacitor, for example an X7R type. When limiting the maximum input capacitance to 35 pF and the minimum operating temperature to −20 °C then the minimum operating voltage can be reduced to 2.8 V. The main limitation when lowering the supply voltage is a reduction in the range of the Vi(CPC) voltage, which is specified from 0.6 V to VDD − 0.3 V. Reducing the Vi(CPC) working range is equivalent to reducing the input capacitance range. Additionally, Vi(CPC) increases with decreasing temperature, as illustrated in Figure 13 and Figure 14. This means that it is possible to lower the supply voltage if the minimum temperature will be raised accordingly. For the choice of proper component values for a given application, the component specifications in Table 5 and Table 6 must be followed. PCF8883 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved. Product data sheet Rev. 2 — 8 March 2011 17 of 25 NXP Semiconductors PCF8883 Capacitive proximity switch with auto-calibration 14. Package outline SOIC8: plastic small outline package; 8 leads; body width 3.9 mm PCF8883 D E A X c y HE v A Z 8 5 A2 A1 (A3) A θ pin 1 index L detail X Lp 1 e bp 4 w 0 Dimensions Unit mm A A1 0.25 0.10 0.0098 0.0040 A2 1.48 0.25 1.27 0.0582 0.01 0.0500 0.014 0.36 0.019 0.190 4.8 A3 bp 0.49 c 0.249 D(1) 5.0 2.5 scale E(2) 3.99 1.27 3.82 0.05 0.0075 0.189 0.150 0.229 5.8 0.244 0.0098 0.196 0.157 e HE 6.2 5 mm L 1.05 Lp 0.86 v w y 0.1 Z(1) 0.7 θ 8° 0° max 1.73 nom min 1.37 0.25 0.25 0.41 0.034 0.3 0.01 0.01 0.004 max 0.068 inches nom min 0.054 0.028 8° 0.012 0° 0.041 0.016 Note 1. Plastic or metal protrusions of 0.15 mm (0.006 inch) maximum per side are not included. 2. Plastic or metal protrusions of 0.25 mm (0.01 inch) maximum per side are not included. Outline version PCF8883 References IEC JEDEC MS-012-AA JEITA European projection pcf8883_po Issue date 09-06-03 Fig 16. Package outline of PCF8883 (SOIC8) PCF8883 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved. Product data sheet Rev. 2 — 8 March 2011 18 of 25 NXP Semiconductors PCF8883 Capacitive proximity switch with auto-calibration Fig 17. Three dimensional package drawing of PCF8883 (SOIC8) 15. Soldering of SMD packages This text provides a very brief insight into a complex technology. A more in-depth account of soldering ICs can be found in Application Note AN10365 “Surface mount reflow soldering description”. 15.1 Introduction to soldering Soldering is one of the most common methods through which packages are attached to Printed Circuit Boards (PCBs), to form electrical circuits. The soldered joint provides both the mechanical and the electrical connection. There is no single soldering method that is ideal for all IC packages. Wave soldering is often preferred when through-hole and Surface Mount Devices (SMDs) are mixed on one printed wiring board; however, it is not suitable for fine pitch SMDs. Reflow soldering is ideal for the small pitches and high densities that come with increased miniaturization. 15.2 Wave and reflow soldering Wave soldering is a joining technology in which the joints are made by solder coming from a standing wave of liquid solder. The wave soldering process is suitable for the following: • Through-hole components • Leaded or leadless SMDs, which are glued to the surface of the printed circuit board Not all SMDs can be wave soldered. Packages with solder balls, and some leadless packages which have solder lands underneath the body, cannot be wave soldered. Also, leaded SMDs with leads having a pitch smaller than ~0.6 mm cannot be wave soldered, due to an increased probability of bridging. The reflow soldering process involves applying solder paste to a board, followed by component placement and exposure to a temperature profile. Leaded packages, packages with solder balls, and leadless packages are all reflow solderable. Key characteristics in both wave and reflow soldering are: • • • • • • Board specifications, including the board finish, solder masks and vias Package footprints, including solder thieves and orientation The moisture sensitivity level of the packages Package placement Inspection and repair Lead-free soldering versus SnPb soldering PCF8883 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved. Product data sheet Rev. 2 — 8 March 2011 19 of 25 NXP Semiconductors PCF8883 Capacitive proximity switch with auto-calibration 15.3 Wave soldering Key characteristics in wave soldering are: • Process issues, such as application of adhesive and flux, clinching of leads, board transport, the solder wave parameters, and the time during which components are exposed to the wave • Solder bath specifications, including temperature and impurities 15.4 Reflow soldering Key characteristics in reflow soldering are: • Lead-free versus SnPb soldering; note that a lead-free reflow process usually leads to higher minimum peak temperatures (see Figure 18) than a SnPb process, thus reducing the process window • Solder paste printing issues including smearing, release, and adjusting the process window for a mix of large and small components on one board • Reflow temperature profile; this profile includes preheat, reflow (in which the board is heated to the peak temperature) and cooling down. It is imperative that the peak temperature is high enough for the solder to make reliable solder joints (a solder paste characteristic). In addition, the peak temperature must be low enough that the packages and/or boards are not damaged. The peak temperature of the package depends on package thickness and volume and is classified in accordance with Table 7 and 8 Table 7. SnPb eutectic process (from J-STD-020C) Package reflow temperature (°C) Volume (mm3) < 350 < 2.5 ≥ 2.5 Table 8. 235 220 Lead-free process (from J-STD-020C) Package reflow temperature (°C) Volume (mm3) < 350 < 1.6 1.6 to 2.5 > 2.5 260 260 250 350 to 2000 260 250 245 > 2000 260 245 245 ≥ 350 220 220 Package thickness (mm) Package thickness (mm) Moisture sensitivity precautions, as indicated on the packing, must be respected at all times. Studies have shown that small packages reach higher temperatures during reflow soldering, see Figure 18. PCF8883 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved. Product data sheet Rev. 2 — 8 March 2011 20 of 25 NXP Semiconductors PCF8883 Capacitive proximity switch with auto-calibration temperature maximum peak temperature = MSL limit, damage level minimum peak temperature = minimum soldering temperature peak temperature time 001aac844 MSL: Moisture Sensitivity Level Fig 18. Temperature profiles for large and small components For further information on temperature profiles, refer to Application Note AN10365 “Surface mount reflow soldering description”. 16. Abbreviations Table 9. Acronym CMOS HBM IC MM MOS MOSFET MSL PCB RC RF SMD Abbreviations Description Complementary Metal Oxide Semiconductor Human Body Model Integrated Circuit Machine Model Metal Oxide Semiconductor Metal–Oxide–Semiconductor Field-Effect Transistor Moisture Sensitivity Level Printed-Circuit Board Resistance-Capacitance Radio Frequency Surface Mount Device PCF8883 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved. Product data sheet Rev. 2 — 8 March 2011 21 of 25 NXP Semiconductors PCF8883 Capacitive proximity switch with auto-calibration 17. References [1] [2] [3] [4] [5] [6] [7] [8] [9] AN10365 — Surface mount reflow soldering description AN10832 — PCF8883 - capacitive proximity switch with auto-calibration IEC 60134 — Rating systems for electronic tubes and valves and analogous semiconductor devices IEC 61340-5 — Protection of electronic devices from electrostatic phenomena IPC/JEDEC J-STD-020D — Moisture/Reflow Sensitivity Classification for Nonhermetic Solid State Surface Mount Devices JESD22-A114 — Electrostatic Discharge (ESD) Sensitivity Testing Human Body Model (HBM) JESD22-A115 — Electrostatic Discharge (ESD) Sensitivity Testing Machine Model (MM) JESD78 — IC Latch-Up Test JESD625-A — Requirements for Handling Electrostatic-Discharge-Sensitive (ESDS) Devices [10] NX3-00092 — NXP store and transport requirements [11] UM10370 — PCF8883 evaluation board 18. Revision history Table 10. Revision history Release date 20110308 Data sheet status Product data sheet Change notice Supersedes PCF8883_1 Document ID PCF8883 v.2 Modifications: PCF8883_1 • • Added low voltage specification Deleted ILI value in Table 5 Product data sheet - 20091016 PCF8883 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved. Product data sheet Rev. 2 — 8 March 2011 22 of 25 NXP Semiconductors PCF8883 Capacitive proximity switch with auto-calibration 19. Legal information 19.1 Data sheet status Document status[1][2] Objective [short] data sheet Preliminary [short] data sheet Product [short] data sheet [1] [2] [3] Product status[3] Development Qualification Production Definition This document contains data from the objective specification for product development. This document contains data from the preliminary specification. This document contains the product specification. Please consult the most recently issued document before initiating or completing a design. The term ‘short data sheet’ is explained in section “Definitions”. The product status of device(s) described in this document may have changed since this document was published and may differ in case of multiple devices. The latest product status information is available on the Internet at URL http://www.nxp.com. 19.2 Definitions Draft — The document is a draft version only. The content is still under internal review and subject to formal approval, which may result in modifications or additions. NXP Semiconductors does not give any representations or warranties as to the accuracy or completeness of information included herein and shall have no liability for the consequences of use of such information. Short data sheet — A short data sheet is an extract from a full data sheet with the same product type number(s) and title. A short data sheet is intended for quick reference only and should not be relied upon to contain detailed and full information. For detailed and full information see the relevant full data sheet, which is available on request via the local NXP Semiconductors sales office. In case of any inconsistency or conflict with the short data sheet, the full data sheet shall prevail. Product specification — The information and data provided in a Product data sheet shall define the specification of the product as agreed between NXP Semiconductors and its customer, unless NXP Semiconductors and customer have explicitly agreed otherwise in writing. In no event however, shall an agreement be valid in which the NXP Semiconductors product is deemed to offer functions and qualities beyond those described in the Product data sheet. malfunction of an NXP Semiconductors product can reasonably be expected to result in personal injury, death or severe property or environmental damage. NXP Semiconductors accepts no liability for inclusion and/or use of NXP Semiconductors products in such equipment or applications and therefore such inclusion and/or use is at the customer’s own risk. Applications — Applications that are described herein for any of these products are for illustrative purposes only. NXP Semiconductors makes no representation or warranty that such applications will be suitable for the specified use without further testing or modification. Customers are responsible for the design and operation of their applications and products using NXP Semiconductors products, and NXP Semiconductors accepts no liability for any assistance with applications or customer product design. It is customer’s sole responsibility to determine whether the NXP Semiconductors product is suitable and fit for the customer’s applications and products planned, as well as for the planned application and use of customer’s third party customer(s). Customers should provide appropriate design and operating safeguards to minimize the risks associated with their applications and products. NXP Semiconductors does not accept any liability related to any default, damage, costs or problem which is based on any weakness or default in the customer’s applications or products, or the application or use by customer’s third party customer(s). Customer is responsible for doing all necessary testing for the customer’s applications and products using NXP Semiconductors products in order to avoid a default of the applications and the products or of the application or use by customer’s third party customer(s). NXP does not accept any liability in this respect. Limiting values — Stress above one or more limiting values (as defined in the Absolute Maximum Ratings System of IEC 60134) will cause permanent damage to the device. Limiting values are stress ratings only and (proper) operation of the device at these or any other conditions above those given in the Recommended operating conditions section (if present) or the Characteristics sections of this document is not warranted. Constant or repeated exposure to limiting values will permanently and irreversibly affect the quality and reliability of the device. Terms and conditions of commercial sale — NXP Semiconductors products are sold subject to the general terms and conditions of commercial sale, as published at http://www.nxp.com/profile/terms, unless otherwise agreed in a valid written individual agreement. In case an individual agreement is concluded only the terms and conditions of the respective agreement shall apply. NXP Semiconductors hereby expressly objects to applying the customer’s general terms and conditions with regard to the purchase of NXP Semiconductors products by customer. No offer to sell or license — Nothing in this document may be interpreted or construed as an offer to sell products that is open for acceptance or the grant, conveyance or implication of any license under any copyrights, patents or other industrial or intellectual property rights. Export control — This document as well as the item(s) described herein may be subject to export control regulations. Export might require a prior authorization from national authorities. © NXP B.V. 2011. All rights reserved. 19.3 Disclaimers Limited warranty and liability — Information in this document is believed to be accurate and reliable. However, NXP Semiconductors does not give any representations or warranties, expressed or implied, as to the accuracy or completeness of such information and shall have no liability for the consequences of use of such information. In no event shall NXP Semiconductors be liable for any indirect, incidental, punitive, special or consequential damages (including - without limitation - lost profits, lost savings, business interruption, costs related to the removal or replacement of any products or rework charges) whether or not such damages are based on tort (including negligence), warranty, breach of contract or any other legal theory. Notwithstanding any damages that customer might incur for any reason whatsoever, NXP Semiconductors’ aggregate and cumulative liability towards customer for the products described herein shall be limited in accordance with the Terms and conditions of commercial sale of NXP Semiconductors. Right to make changes — NXP Semiconductors reserves the right to make changes to information published in this document, including without limitation specifications and product descriptions, at any time and without notice. This document supersedes and replaces all information supplied prior to the publication hereof. Suitability for use — NXP Semiconductors products are not designed, authorized or warranted to be suitable for use in life support, life-critical or safety-critical systems or equipment, nor in applications where failure or PCF8883 All information provided in this document is subject to legal disclaimers. Product data sheet Rev. 2 — 8 March 2011 23 of 25 NXP Semiconductors PCF8883 Capacitive proximity switch with auto-calibration liability, damages or failed product claims resulting from customer design and use of the product for automotive applications beyond NXP Semiconductors’ standard warranty and NXP Semiconductors’ product specifications. Quick reference data — The Quick reference data is an extract of the product data given in the Limiting values and Characteristics sections of this document, and as such is not complete, exhaustive or legally binding. Non-automotive qualified products — Unless this data sheet expressly states that this specific NXP Semiconductors product is automotive qualified, the product is not suitable for automotive use. It is neither qualified nor tested in accordance with automotive testing or application requirements. NXP Semiconductors accepts no liability for inclusion and/or use of non-automotive qualified products in automotive equipment or applications. In the event that customer uses the product for design-in and use in automotive applications to automotive specifications and standards, customer (a) shall use the product without NXP Semiconductors’ warranty of the product for such automotive applications, use and specifications, and (b) whenever customer uses the product for automotive applications beyond NXP Semiconductors’ specifications such use shall be solely at customer’s own risk, and (c) customer fully indemnifies NXP Semiconductors for any 19.4 Licenses ICs with capacitive sensing functionality This NXP Semiconductors IC is made under license to European Patent No. 0723339, owned by EDISEN - SENSOR SYSTEME GmbH & CO KG and counterparts. Any license fee is included in the purchase price. 19.5 Trademarks Notice: All referenced brands, product names, service names and trademarks are the property of their respective owners. I2C-bus — logo is a trademark of NXP B.V. 20. Contact information For more information, please visit: http://www.nxp.com For sales office addresses, please send an email to: salesaddresses@nxp.com PCF8883 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved. Product data sheet Rev. 2 — 8 March 2011 24 of 25 NXP Semiconductors PCF8883 Capacitive proximity switch with auto-calibration 21. Contents 1 2 3 4 5 6 7 7.1 7.2 8 8.1 8.2 9 10 11 12 12.1 12.2 12.3 13 14 15 15.1 15.2 15.3 15.4 16 17 18 19 19.1 19.2 19.3 19.4 19.5 20 21 General description . . . . . . . . . . . . . . . . . . . . . . 1 Features and benefits . . . . . . . . . . . . . . . . . . . . 1 Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Ordering information . . . . . . . . . . . . . . . . . . . . . 2 Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Pinning information . . . . . . . . . . . . . . . . . . . . . . 4 Pinning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Pin description . . . . . . . . . . . . . . . . . . . . . . . . . 4 Functional description . . . . . . . . . . . . . . . . . . . 5 Output switching modes . . . . . . . . . . . . . . . . . . 7 Voltage regulator. . . . . . . . . . . . . . . . . . . . . . . . 8 Limiting values. . . . . . . . . . . . . . . . . . . . . . . . . . 9 Static characteristics. . . . . . . . . . . . . . . . . . . . 10 Dynamic characteristics . . . . . . . . . . . . . . . . . 11 Characteristic curves . . . . . . . . . . . . . . . . . . . 12 Power consumption . . . . . . . . . . . . . . . . . . . . 12 Typical reaction time . . . . . . . . . . . . . . . . . . . . 13 Reservoir capacitor voltage . . . . . . . . . . . . . . 15 Application information. . . . . . . . . . . . . . . . . . 16 Package outline . . . . . . . . . . . . . . . . . . . . . . . . 18 Soldering of SMD packages . . . . . . . . . . . . . . 19 Introduction to soldering . . . . . . . . . . . . . . . . . 19 Wave and reflow soldering . . . . . . . . . . . . . . . 19 Wave soldering . . . . . . . . . . . . . . . . . . . . . . . . 20 Reflow soldering . . . . . . . . . . . . . . . . . . . . . . . 20 Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . 21 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Revision history . . . . . . . . . . . . . . . . . . . . . . . . 22 Legal information. . . . . . . . . . . . . . . . . . . . . . . 23 Data sheet status . . . . . . . . . . . . . . . . . . . . . . 23 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Disclaimers . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Licenses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Trademarks. . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Contact information. . . . . . . . . . . . . . . . . . . . . 24 Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Please be aware that important notices concerning this document and the product(s) described herein, have been included in section ‘Legal information’. © NXP B.V. 2011. All rights reserved. For more information, please visit: http://www.nxp.com For sales office addresses, please send an email to: salesaddresses@nxp.com Date of release: 8 March 2011 Document identifier: PCF8883