pca8885 NXP Semiconductors, pca8885 Datasheet
pca8885
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pca8885 Summary of contents
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... Rev. 1 — 24 November 2011 1. General description The integrated circuit PCA8885 is a capacitive 8-channel proximity switch that uses a patented (EDISEN) method to detect a change in capacitance on remote sensing plates. Changes in the static capacitances (as opposed to dynamic capacitance changes) are automatically compensated using continuous auto-calibration. Remote sensing plates (for example, conductive foils) can be connected to the IC input channels operate independently of each other ...
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... Ordering information Package Name Description TSSOP28 plastic small outline package; 28 leads; body width 4.4 mm Marking codes All information provided in this document is subject to legal disclaimers. Rev. 1 — 24 November 2011 PCA8885 Marking code PCA8885TS © NXP B.V. 2011. All rights reserved. Version PCA8885TS ...
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... NXP Semiconductors 6. Block diagram CLK_IN OSCILLATOR CLK_OUT t dch(ref) GENERATOR IN0 CPC0 IN1 CPC1 IN7 CPC7 Fig 1. Block diagram of PCA8885 PCA8885 Objective data sheet Capacitive 8-channel proximity switch with auto-calibration TEST CLK TIMING CONTROL TA TA0 to TA7 CHANNEL 0 CHANNEL 1 CHANNEL All information provided in this document is subject to legal disclaimers. ...
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... IN5 6 IN4 IN3 7 IN2 8 IN1 9 10 IN0 11 CPC7 CPC6 12 CPC5 13 CPC4 14 Top view. For mechanical details, see Pin configuration for TSSOP28 (PCA8885TS) Pin description Pin Type PCA8885TS 1 output [1] 2 supply analog input/output analog input/output [2] 19 supply 20 input 21 input/output serial data line ...
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... PCA8885TS 26 supply 27 input 28 input All information provided in this document is subject to legal disclaimers. Rev. 1 — 24 November 2011 PCA8885 Description supply voltage interrupt input for chip cascading; connect not used DD clock input; for the secondary chip when the primary chip provides the clock signal and should be electrically isolated ...
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... UP t dch0 DOWN CDN V CUP DD(INTREGD dch7 DOWN CDN All information provided in this document is subject to legal disclaimers. Rev. 1 — 24 November 2011 PCA8885 ) of an internal dch(ref) and then discharged via a resistor to Figure 3). IN7 IN0 sampling sampling CHANNEL 0 V DD(INTREGD) OUT0 CTR ...
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... If the reference comparator switched first, then a pulse is given on CUP. If the sensor comparator switched first, then a pulse is given on CDN. illustrates the functional principle of the PCA8885. The pulses control the charge on the external capacitors C Every time a pulse is given on CUP, the capacitor C source (I small increment ...
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... NXP Semiconductors 9. Commands The operation of the PCA8885 can be controlled by 12 commands and four configuration- and status-registers (see programmed using single commands without associated data transfer. The configuration register can however also be written using the write-config command. The clock and mask registers can only be programmed using the write-clock and write-mask commands. ...
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... The read-sensor command is the main transaction to read the actual state information of the sensor state register SENS. If the R/W bit (LSB of the I the PCA8885 regards the transaction as the read-sensor command. The read-sensor command transaction supports a repeated reading of the SENS register (see on page return their SENS register content in a single transaction The protocols for the repeated read mode and the alternating read mode are described in Section 13 ...
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... NXP Semiconductors 10. Registers The PCA8885 has four registers storing the configuration and the status information of the device. 10.1 Register overview Table 5. The bit position labeled not relevant; if read, it can be either logic 0 or logic 1. Register name CONFIG SENS CLKREG MASK 10.2 Register: CONFIG Table 6 ...
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... Default value. All bits in this register can be written and read with the write-config and read-config commands. 10.2.1 Operating modes 10.2.1.1 Main operating modes The PCA8885 can operate in three operating modes stand-alone device cascade as a primary-chip or a secondary-chip (see Table 7. Conditions of clock source ...
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... The PCA8885 provides two mechanisms to inform the system controller that a sensor activity has been detected. 10.2.2.1 Interrupt output INT The PCA8885 has an interrupt output, INT, to flag to the system controller that a capacitive event has been detected. The controller can then fetch the sensor state by reading the SENS register over the I ...
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... Interrupt over the I In applications where the sensing plates are remote from the microcontroller, the interrupt line can be saved by enabling the interrupt over I The PCA8885 allows to flag an interrupt over the I like an I START condition immediately followed by a STOP condition illustrated in No further I Fig 5 ...
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... PCA8885 © NXP B.V. 2011. All rights reserved ...
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... NXP Semiconductors All bits in this register can be written and read with the write-clock and read-clock commands. 10.4.1 Clock generation and frequency adjustment The PCA8885 contains an integrated oscillator as main clock source. The oscillator runs nominally at f can be tuned (see f = osc The values of m can be varied in the range 0.5 m 1.75, where m = 1.0 corresponds to the default value of FRQF[2:0] = 100 ...
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... Rev. 1 — 24 November 2011 Description enable or disable the respective sensor [1] channels IN0 to IN7 sensor channel is disabled sensor channel is enabled Table 6) is set logic 0, then the Table 6) is set logic 1, only channels PCA8885 Section 12) is © NXP B.V. 2011. All rights reserved ...
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... While the analog part of the circuit is powered from V registers are powered from V mode, and the register values are maintained when V Fig 8. Figure 8 the operational range of the PCA8885. The analog part of the circuit and the switch logic is powered from V Therefore the I maintained when V PCA8885 ...
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... VROF bit DD domain, the circuit starts with the sensor DD(INTREGD) All information provided in this document is subject to legal disclaimers. Rev. 1 — 24 November 2011 PCA8885 DD(INTREGD) level is reached, the DD(INTREGD) © NXP B.V. 2011. All rights reserved ...
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... SDA SCL data line stable; data valid Bit transfer S START condition All information provided in this document is subject to legal disclaimers. Rev. 1 — 24 November 2011 2 C-bus interface of the PCA8885 is Fast-mode Figure 9). change of data allowed mba607 Figure 10. P STOP condition PCA8885 2 C Interface. SDA ...
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... C-bus All information provided in this document is subject to legal disclaimers. Rev. 1 — 24 November 2011 SLAVE MASTER TRANSMITTER/ TRANSMITTER RECEIVER Figure 12. not acknowledge acknowledge 2 8 clock pulse for acknowledgement PCA8885 Figure 11. MASTER TRANSMITTER/ RECEIVER mga807 9 mbc602 © NXP B.V. 2011. All rights reserved ...
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... Fast-mode Plus specification are given in 13.7 Reading sensor data The PCA8885 supports direct reading of the sensor state from the SENS register after sending the address - the R/W bit is immediately set to logic 1 without sending a command, the circuit recognizes that it must immediately return the content of the SENS ...
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... Fig 16. Reading sensor data, alternately from primary-chip and secondary-chip It must be noted, that for this alternate data transfer only one PCA8885 has to be addressed. By definition the primary-chip must be addressed (A0 bit in the address set to logic 0). In this particular case, the secondary-chip reacts on the address of the primary-chip ...
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... NXP Semiconductors • The 7-bit I applied to pin A0 (V two PCA8885 can be addressed on the same bus without the need for different hard coded I • The sensor activity can be synchronized, so that interference between the sensors of the different chips is avoided. One chip is considered to be the primary-chip. It provides the sample clock on pin CLK_OUT ...
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... Objective data sheet Capacitive 8-channel proximity switch with auto-calibration V DD(INTREGD) IN0 to IN7, CPC0 to CPC7 PCA8885 All information provided in this document is subject to legal disclaimers. Rev. 1 — 24 November 2011 PCA8885 V DD CLK_IN, INT, INT_IN, TEST, SLEEP, A0, CLK_OUT SCL, SDA V SS 013aaa578 © NXP B.V. 2011. All rights reserved. ...
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... Ref. 9 “JESD78” All information provided in this document is subject to legal disclaimers. Rev. 1 — 24 November 2011 PCA8885 Conditions Min 0.5 0.5 0.5 on all input pins 50 30 10 ...
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... 0 pins V and DD(INTREGD ceramic chip capacitor DD are settled. CPC can be applied for high sensitivity applications, but switching reliability can suffer. All information provided in this document is subject to legal disclaimers. Rev. 1 — 24 November 2011 PCA8885 Min Typ Max 2.5 - 5.5 2.5 - 3.3 [1] 2.5 2.9 3 ...
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... Fig 19. I PCA8885 Objective data sheet Capacitive 8-channel proximity switch with auto-calibration with respect with respect to temperature DD All information provided in this document is subject to legal disclaimers. Rev. 1 — 24 November 2011 PCA8885 013aaa233 013aaa233 © NXP B.V. 2011. All rights reserved ...
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... NXP Semiconductors (1) <tbd> Fig 20. I PCA8885 Objective data sheet Capacitive 8-channel proximity switch with auto-calibration with respect to sampling frequency DD All information provided in this document is subject to legal disclaimers. Rev. 1 — 24 November 2011 PCA8885 013aaa233 © NXP B.V. 2011. All rights reserved ...
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... CPC s internal RC oscillator FRQF[2:0] = 111 FRQF[2:0] = 100 FRQF[2:0] = 000 kHz s 2 interrupt over I C All information provided in this document is subject to legal disclaimers. Rev. 1 — 24 November 2011 PCA8885 Min Typ Max Unit - 200 - ms 90 112 140 kHz [ ...
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... LOW SCL t VD;ACK t t HD;STA All information provided in this document is subject to legal disclaimers. Rev. 1 — 24 November 2011 013aaa233 t VD;DAT t HIGH BUF t SU;STO clock PCA8885 cont. cont clock 013aaa557 © NXP B.V. 2011. All rights reserved ...
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... RC IN[3] opt. RC PCA8885 IN[7] opt. RC CLK_IN (1) INT_IN CPC[ 100 CPC[0] or left open. SS All information provided in this document is subject to legal disclaimers. Rev. 1 — 24 November 2011 PCA8885 V 100 DD(INTREGD) 100 nF SCL SDA SLEEP A0 CLK_OUT to MCU INT CPC[ ...
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... IN2 14 IN3 IN3 15 IN4 IN4 16 IN5 IN3 IN2 IN5 17 IN6 IN6 18 IN7 IN7 IN6 28 IN7 IN6 IN7 PCA8885 IN4 20 IN5 21 IN6 22 IN7 013aaa580 © NXP B.V. 2011. All rights reserved ...
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... All information provided in this document is subject to legal disclaimers. Rev. 1 — 24 November 2011 PCA8885 IN4 IN3 IN2 IN1 ...
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... All information provided in this document is subject to legal disclaimers. Rev. 1 — 24 November 2011 V DD 100 100 nF SCL SDA SLEEP (1) A0 INT 100 nF 100 nF SCL SDA SLEEP (1) A0 INT ( 013aaa581 PCA8885 to MCU © NXP B.V. 2011. All rights reserved ...
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... Section 16 on page 26 All information provided in this document is subject to legal disclaimers. Rev. 1 — 24 November 2011 4 sensor arrangement. In this configuration, can help to bring the input F is reduced. When maximum CPC must be followed. PCA8885 © NXP B.V. 2011. All rights reserved ...
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... Note 1. Plastic or metal protrusions of 0.15 mm maximum per side are not included. Outline version IEC PCA8885TS Fig 26. Package outline PCA8885TS (TSSOP28) PCA8885 Objective data sheet Capacitive 8-channel proximity switch with auto-calibration exposed pad scale (1) ...
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... NXP Semiconductors Fig 27. Three-dimensional package drawing of PCA8885 21. 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”. 21.1 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 ...
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... Package reflow temperature (C) 3 Volume (mm ) < 350 260 260 250 Figure 28. All information provided in this document is subject to legal disclaimers. Rev. 1 — 24 November 2011 PCA8885 Figure 28) than a SnPb process, thus 350 220 220 350 to 2 000 > 2 000 260 260 250 245 ...
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... Metal Oxide Semiconductor Metal–Oxide–Semiconductor Field-Effect Transistor Moisture Sensitivity Level Printed-Circuit Board Resistance-Capacitance Radio Frequency Surface Mount Device All information provided in this document is subject to legal disclaimers. Rev. 1 — 24 November 2011 PCA8885 peak temperature time 001aac844 © NXP B.V. 2011. All rights reserved ...
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... SNV-FA-01-02 — Marking Formats Integrated Circuits [13] UM10204 — I [14] UM10505 — OM11057 quick start guide 24. Revision history Table 19. Revision history Document ID Release date PCA8885 v.1 20111124 PCA8885 Objective data sheet Capacitive 8-channel proximity switch with auto-calibration 2 C-bus specification and user manual Data sheet status Objective data sheet All information provided in this document is subject to legal disclaimers ...
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... All information provided in this document is subject to legal disclaimers. Rev. 1 — 24 November 2011 PCA8885 © NXP B.V. 2011. All rights reserved ...
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... Notice: All referenced brands, product names, service names and trademarks are the property of their respective owners C-bus — logo is a trademark of NXP B.V. http://www.nxp.com salesaddresses@nxp.com All information provided in this document is subject to legal disclaimers. Rev. 1 — 24 November 2011 PCA8885 © NXP B.V. 2011. All rights reserved ...
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... Package outline Soldering of SMD packages . . . . . . . . . . . . . . 37 Introduction to soldering Wave and reflow soldering Wave soldering . . . . . . . . . . . . . . . . . . . . . . . 38 Reflow soldering . . . . . . . . . . . . . . . . . . . . . . 38 Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . 39 References Revision history . . . . . . . . . . . . . . . . . . . . . . . 40 Legal information . . . . . . . . . . . . . . . . . . . . . . 41 Data sheet status . . . . . . . . . . . . . . . . . . . . . . 41 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Disclaimers . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Licenses Trademarks . . . . . . . . . . . . . . . . . . . . . . . . . . 42 Contact information . . . . . . . . . . . . . . . . . . . . 42 Contents Date of release: 24 November 2011 Document identifier: PCA8885 All rights reserved. ...