PCA8886
Dual channel capacitive proximity switch with
auto-calibration and large voltage operating range
Rev. 3 — 14 March 2014
Product data sheet
1. General description
The PCA8886 is a low power dual channel capacitive proximity switch that uses a
patented (EDISEN) digital method to detect a change in capacitance on remote sensing
plates. Changes in the static capacitance (as opposed to dynamic capacitance changes)
are automatically compensated using continuous auto-calibration. Remote sensing plates
(for example, conductive foil) can be connected directly to the IC
1
or remotely using a
coaxial cable.
2. Features and benefits
Dynamic proximity switch
Digital processing method
Automatic calibration
Adjustable sensitivity, can be made very high
Adjustable response time
Wide input capacitance range (10 pF to 60 pF)
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)
Output configurable as push-button, toggle, or pulse
Wide voltage operating range (V
DD
= 3 V to 9 V)
Designed for battery powered applications (I
DD
= 6
A,
typical)
Large temperature operating range (T
amb
=
40 C
to +85
C)
AEC-Q100 compliant for automotive applications
Available in TSSOP16
3. Applications
Proximity detection
Proximity sensing in
Door locks and grips
Portable entertainment units
Computing tablets
Switch for medical applications
Dashboard: switch to toggle menus and resetting trip counter
Switch for use in explosive environments
1.
The definition of the abbreviations and acronyms used in this data sheet can be found in
Section 20.
NXP Semiconductors
PCA8886
Dual channel capacitive proximity switch with auto-calibration
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 (for example, tap) as switch
Hermetically sealed keys on a keyboard
4. Ordering information
Table 1.
Ordering information
Package
Name
PCA8886TS
TSSOP16
Description
plastic thin shrink small outline package;
16 leads; body width 4.4 mm
Version
PCA8886
Type number
4.1 Ordering options
Table 2.
Ordering options
Orderable part number Sales item
(12NC)
PCA8886TS/Q900/1,1
935297325118
Delivery form
tape and reel, 13 inch
IC
revision
1
Product type number
PCA8886TS/Q900/1
5. Marking
Table 3.
Marking codes
Marking code
PCA8886
Product type number
PCA8886TS/Q900/1
PCA8886
All information provided in this document is subject to legal disclaimers.
© NXP Semiconductors N.V. 2014. All rights reserved.
Product data sheet
Rev. 3 — 14 March 2014
2 of 30
NXP Semiconductors
PCA8886
Dual channel capacitive proximity switch with auto-calibration
6. Block diagram
The PCA8886 integrates two identical capacitive proximity switches which can be configured
separately.
Fig 1.
Block diagram of PCA8886
PCA8886
All information provided in this document is subject to legal disclaimers.
© NXP Semiconductors N.V. 2014. All rights reserved.
Product data sheet
Rev. 3 — 14 March 2014
3 of 30
NXP Semiconductors
PCA8886
Dual channel capacitive proximity switch with auto-calibration
7. Pinning information
7.1 Pinning
Top view. For mechanical details, see
Figure 16.
Fig 2.
Pin configuration of PCA8886TS (TSSOP16)
7.2 Pin description
Table 4.
Pin description
Input or input/output pins must always be at a defined level (V
SS
or V
DD
) unless otherwise specified.
Symbol
Pin
TSSOP16
(PCA8886TS)
IN1
TYPE1
CPC1
V
SS1
IN2
TYPE2
CPC2
V
SS2
V
DD2
OUT2
CLIN2
V
DD(INTREGD)2[1]
V
DD1
OUT1
CLIN1
V
DD(INTREGD)1[1]
[1]
Type
Description
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
analog input/output
input
analog input/output
supply
analog input/output
input
analog input/output
supply
supply
output
analog input/output
supply
supply
output
analog input/output
supply
sensor input 1
select output configuration of pin OUT1
sensitivity setting 1
ground supply voltage 1
sensor input 2
select output configuration of pin OUT2
sensitivity setting 2
ground supply voltage 2
supply voltage 2
switch output 2
sampling rate setting 2
internal regulated supply voltage
output 2
supply voltage 1
switch output 1
sampling rate setting 1
internal regulated supply voltage
output 1
The internal regulated supply voltage outputs must be decoupled with a decoupling capacitor to V
SS[1:2]
.
PCA8886
All information provided in this document is subject to legal disclaimers.
© NXP Semiconductors N.V. 2014. All rights reserved.
Product data sheet
Rev. 3 — 14 March 2014
4 of 30
NXP Semiconductors
PCA8886
Dual channel capacitive proximity switch with auto-calibration
8. Functional description
Figure 3
and
Figure 4
show the functional principle of one channel of the PCA8886.
The discharge time (t
dch
) of a chip-internal RC timing circuit, to which the external sensing
plates are connected via pins IN[1:2], is compared to the discharge time (t
dch(ref)
) of a
second chip-internal reference RC timing circuit. Both RC timing circuits are periodically
charged from V
DD(INTREGD)[1:2]
via identical switches and then discharged via a resistor to
ground (V
SS
). Both switches are synchronized.
Fig 3.
Functional diagram of the sensor logic (one channel)
The charge-discharge cycle is governed by the sampling rate (f
s
). If the voltage of one of
the RC timing circuits falls below the internal reference voltage V
ref
, the respective
comparator output becomes 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 C
CPC
on pins CPC[1:2]. Every
time a pulse is given on CUP, capacitor C
CPC
is charged from V
DD(INTREGD)
for a fixed time
causing the voltage on C
CPC
to rise. Likewise when a pulse occurs on CDN, capacitor
C
CPC
is connected to a current sink to ground for a fixed time causing the voltage on C
CPC
to fall.
PCA8886
All information provided in this document is subject to legal disclaimers.
© NXP Semiconductors N.V. 2014. All rights reserved.
Product data sheet
Rev. 3 — 14 March 2014
5 of 30
单片机
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
