CLARE CPC7695BCTR

CPC7695
Line Card Access Switch
Features
Description
• Improved switch dV/dt immunity of 1500 V/μs
• Drop-In Replacement for CPC7595
• Replaces CPC7585, and allows removal of
power-up control discrete components
• Enhanced SW8, Ringing Test Switch, breakdown
voltage
• TTL logic level inputs for 3.3V logic interfaces
• Smart logic for power up / hot plug state control
• Small 20 pin or 28 pin SOIC Package
• Monolithic IC reliability
• Low, matched, RON
• Eliminates the need for zero-cross switching
• Flexible switch timing for transition from ringing
mode to talk mode.
• Clean, bounce-free switching
• SLIC tertiary protection via integrated current
limiting, voltage clamping and thermal shutdown
• 5 V operation with power consumption < 10.5 mW
• Intelligent battery monitor
The CPC7695 is a member of Clare’s third-generation
Line Card Access Switch (LCAS) family. This
monolithic 10-pole line card access switch is available
in a 20- or 28-pin SOIC package. It provides the
necessary functions to replace three 2-Form-C
electromechanical relays on analog line cards or
combined voice and data line cards found in central
office, access, and PBX equipment. The device
contains solid state switches for tip and ring line break,
ringing injection and test access. The CPC7695
requires only a +5 V supply and provides stable start
up conditioning during system power up and for hot
plug insertion. Once active, the inputs respond to
traditional TTL logic levels enabling the CPC7695 to
be used with 3.3V only logic.
Ordering Information
CPC7695 part numbers are specified as shown here:
B - 28-pin SOIC delivered 29/Tube, 1000/Reel
Z - 20-pin SOIC delivered 40/Tube, 1000/Reel
Applications
•
•
•
•
•
•
•
•
•
Standard voice linecards
Integrated Voice and Data (IVD) linecards
Central office (CO)
Digital Loop Carrier (DLC)
PBX Systems
Digitally Added Main Line (DAML)
Fiber in the Loop (FITL)
Pair Gain System
Channel Banks
CPC7695 x x xx
TR - Add for Tape & Reel Version
A - With Protection SCR
B - Without Protection SCR
C - With Protection SCR and “Monitor Test State”
Pb
RoHS
2002/95/EC
e3
TTESTin (TCHANTEST)
+5 Vdc
TTESTout (TDROPTEST)
10
8 TRINGING
5
12 VDD
SW7
CPC7695
X
Tip
TLINE
7
X SW5 X SW3
X
X SW9
6 TBAT
SW1
Ring
Secondary
Protection
SLIC
SW2
RLINE 22
X
X SW10
X SW6 X SW4
SCR
Trip
Circuit
VREF
X
Switch
Control
Logic
SW8
19
RTESTout (RDROPTEST)
20 RRINGING
300Ω (min.)
VBAT
RTESTin (RCHANTEST)
DS-CPC7695 - R00D
RINGING
24
1
FGND
28
14 13
DGND
L
A
T
C
H
23 RBAT
17
16
15
18
INTESTin
INRINGING
INTESTout
LATCH
TSD
VBAT
NOTE 1: Pin assignments are for the 28 pin package.
NOTE 2: Block diagram shown with the optional protection SCR.
PRELIMINARY
1
CPC7695
1. Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1 Package Pinout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.2 Pinout. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.3 Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.4 ESD Rating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.5 General Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.6 Switch Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.6.1 Break Switches, SW1 and SW2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.6.2 Ringing Return Switch, SW3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.6.3 Ringing Switch, SW4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.6.4 TESTout Switches, SW5 and SW6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1.6.5 Ringing Test Return Switch, SW7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
1.6.6 Ringing Test Switch, SW8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
1.6.7 TESTin Switches, SW9 and SW10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
1.7 Digital I/O Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
1.8 Voltage and Power Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
1.9 Protection Circuitry Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
1.10 Truth Tables. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
1.10.1 Truth Table for CPC7695xA and CPC7695xB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
1.10.2 Truth Table for CPC7695xC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
2. Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2 Under Voltage Switch Lock Out Circuitry. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2.2 Hot Plug and Power Up Circuit Design Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3 Switch Logic. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3.1 Start-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3.2 Switch Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3.3 Make-Before-Break Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3.4 Break-Before-Make Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3.5 Alternate Break-Before-Make Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.4 Data Latch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.5 TSD Pin Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.6 Ringing Switch Zero-Cross Current Turn Off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.7 Power Supplies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.8 Battery Voltage Monitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.9 Protection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.9.1 Diode Bridge/SCR. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.9.2 Current Limiting function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.10 Thermal Shutdown. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.11 External Protection Elements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
15
15
15
15
16
16
16
16
16
17
17
18
18
19
19
19
19
19
20
20
20
3. Manufacturing Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1 Mechanical Dimensions and PCB Land Patterns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1.1 CPC7695Z . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1.2 CPC7695B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2 Tape and Reel Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2.1 CPC7695Z . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2.2 CPC7695B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3 Soldering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.4 Washing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
21
21
21
21
22
22
22
23
23
2
PRELIMINARY
R00D
CPC7695
1. Specifications
1.1 Package Pinout
1.2 Pinout
CPC7695B
28 VBAT
FGND 1
NC 2
27 NC
NC 3
26 NC
NC 4
25 NC
TTESTin 5
20 28
Pin Pin
23 RBAT
TLINE 7
22 RLINE
TRINGING 8
21 NC
20 RRINGING
NC 9
Description
1
FGND
2
NC
No connection
3
NC
No connection
4
NC
No connection
2
5
TTESTin
3
6
TBAT
Tip lead of the SLIC
4
7
TLINE
Tip lead of the line side
5
8
1
24 RTESTin
TBAT 6
Name
Fault ground
Tip lead of the TESTin bus
TRINGING Ringing generator return
TTESTout 10
19 RTESTout
NC 11
18 LATCH
6
10
VDD 12
17 IN TESTin
7
11
NC
No connection
TSD 13
16 INRINGING
8
12
VDD
+5 V supply
15 INTESTout
9
13
TSD
Temperature shutdown pin
DGND 14
9
10 14
NC
Not connected
TTESTout Tip lead of the TESTout bus
DGND
Digital ground
11 15 INTESTout Logic control input
12 16 INRINGING Logic control input
13 17
CPC7695Z
FGND 1
TTESTin 2
19 RTESTin
TBAT 3
18 RBAT
TLINE 4
17 RLINE
14 18
LATCH
15 19
RTESTout Ring lead of the TESTout bus
Data latch enable control input
16 20 RRINGING Ringing generator source
21
NC
No connection
17 22
RLINE
Ring lead of the line side
18 23
RBAT
Ring lead of the SLIC
19 24
RTESTin
Ring lead of the TESTin bus
TRINGING 5
16 RRINGING
25
NC
No connection
6
15 RTESTout
26
NC
No connection
NC 7
14 LATCH
27
NC
No connection
VDD 8
13 INTESTin
20 28
VBAT
Battery supply
TSD 9
12 INRINGING
DGND 10
11 INTESTout
TTESTout
R00D
20 VBAT
INTESTin Logic control input
PRELIMINARY
3
CPC7695
1.3 Absolute Maximum Ratings
Parameter
+5 V power supply (VDD)
1.4 ESD Rating
Minimum Maximum
Unit
ESD Rating (Human Body Model)
1000 V
-0.3
7
V
Battery Supply
-
-85
V
DGND to FGND
separation
-5
+5
V
Logic input voltage
-0.3
VDD +0.3
V
Logic input to switch output
isolation
-
320
V
Switch open-contact
isolation (SW1, SW2, SW3,
SW5, SW6, SW7, SW8,
SW9, SW10)
-
320
V
Switch open-contact
isolation (SW4)
-
Operating relative humidity
465
1.5 General Conditions
Unless otherwise specified, minimum and maximum
values are production testing requirements.
Typical values are characteristic of the device at 25°C
and are the result of engineering evaluations. They are
provided for informational purposes only and are not
part of the manufacturing testing requirements.
Specifications cover the operating temperature range
TA = -40°C to +85°C. Also, unless otherwise specified
all testing is performed with VDD = +5Vdc, logic low
input voltage is 0Vdc and logic high input voltage is
+5Vdc.
V
5
95
%
Operating temperature
-40
+110
°C
Storage temperature
-40
+150
°C
Absolute maximum electrical ratings are at 25°C
Absolute maximum ratings are stress ratings. Stresses in
excess of these ratings can cause permanent damage to
the device. Functional operation of the device at conditions
beyond those indicated in the operational sections of this
data sheet is not implied.
4
PRELIMINARY
R00D
CPC7695
1.6 Switch Specifications
1.6.1 Break Switches, SW1 and SW2
Parameter
Test Conditions
Symbol
Minimum
Typical
Maximum
Unit
1
μA
VSW1 (differential) = TLINE to TBAT
VSW2 (differential) = RLINE to RBAT
All-Off state.
Off-State
Leakage Current
+25° C,
VSW (differential) = -320 V to gnd
VSW (differential) = +260 V to -60 V
0.1
+85° C,
VSW (differential) = -330 V to gnd
VSW (differential) = +270 V to -60 V
ISW
-
-40° C,
VSW (differential) = -310 V to gnd
VSW (differential) = +250 V to -60 V
0.3
0.1
ISW(on) = ±10 mA, ±40 mA,
RBAT and TBAT = -2 V
On Resistance
+25° C
RON
+85° C
-
Per SW1 & SW2 On Resistance test
conditions.
ΔRON
Ω
20.5
28
10.5
-
-
0.15
0.55
-
225
80
150
-
400
425
-
2.5
-
A
-
0.1
-
0.3
1
μA
-
0.1
1500
2100
-
V/μs
-40° C
On Resistance
Matching
14.5
Ω
VSW (on) = ±10 V
DC current limit
+25° C
ISW
+85° C
-40° C
Dynamic current limit
(t ≤ 0.5 μs)
Break switches on, all other switches
off. Apply ±1 kV 10x1000 μs pulse with
appropriate protection in place.
ISW
-
mA
Logic inputs = GND
Logic input to switch
output isolation
+25° C, VSW (TLINE, RLINE) = ±320 V
+85° C, VSW (TLINE, RLINE) = ±330 V
ISW
-40° C, VSW (TLINE, RLINE) = ±310 V
Transient Immunity
R00D
100VPP Square Wave, 100Hz
(Not production tested - limits are
guaranteed by design and quality
control sampling audits.)
dV/dt
PRELIMINARY
5
CPC7695
1.6.2 Ringing Return Switch, SW3
Parameter
Test Conditions
Symbol
Minimum
Typical
Maximum
Unit
1
μA
VSW3 (differential) = TLINE to TRINGING
All-Off state.
Off-State
Leakage Current
+25° C,
VSW (differential) = -320 V to gnd
VSW (differential) = +260 V to -60 V
0.1
+85° C,
VSW (differential) = -330 V to gnd
VSW (differential) = +270 V to -60 V
ISW
-
-40° C,
VSW (differential) = -310 V to gnd
VSW (differential) = +250 V to -60 V
0.3
0.1
ISW(on) = ±0 mA, ±10 mA
On Resistance
+25° C
RON
+85° C
-
-40° C
60
-
85
110
45
-
Ω
VSW (on) = ± 10 V
DC current limit
+25° C
ISW
+85° C
-40° C
Dynamic current limit
(t ≤ 0.5 μs)
Ringing switches on, all other switches
off. Apply ±1 kV 10x1000 μs pulse with
appropriate protection in place.
ISW
-
120
70
85
-
210
-
2.5
-
mA
-
A
1
μA
-
V/μs
Logic inputs = GND
Logic input to switch
output isolation
+25° C, VSW (TRINGING, TLINE)= ±320 V
+85° C, VSW (TRINGING, TLINE)= ±330 V
0.1
ISW
-
-40° C, VSW (TRINGING, TLINE) = ±310 V
Transient Immunity
6
100VPP Square Wave, 100Hz
(Not production tested - limits are
guaranteed by design and quality
control sampling audits.)
0.3
0.1
dV/dt
PRELIMINARY
1500
2100
R00D
CPC7695
1.6.3 Ringing Switch, SW4
Parameter
Test Conditions
Symbol
Minimum
Typical
Maximum
Unit
1
μA
VSW4 (differential) = RLINE to RRINGING
All-Off state.
Off-State
Leakage Current
+25° C
VSW (differential) = -255 V to +210 V
VSW (differential) = +255 V to -210 V
+85° C
VSW (differential) = -270 V to +210 V
VSW (differential) = +270 V to -210 V
0.05
ISW
-
-40° C
VSW (differential) = -245 V to +210 V
VSW (differential) = +245 V to -210 V
0.1
0.05
On Resistance
ISW (on) = ±70 mA, ±80 mA
RON
-
10
15
Ω
On Voltage
ISW (on) = ± 1 mA
VON
-
1.5
3
V
On-State
Leakage Current
Inputs set for ringing -Measure ringing
generator current to ground.
IRINGING
-
0.1
0.25
mA
Steady-State Current*
Inputs set for ringing mode.
ISW
-
-
150
mA
Surge Current*
Ringing switches on, all other switches
off. Apply ±1 kV 10x1000 μs pulse with
appropriate protection in place.
ISW
-
-
2
A
Release Current
SW4 transition from on to off.
IRINGING
-
450
-
μA
1
μA
-
V/μs
Logic inputs = GND
+25° C, VSW (RRINGING, RLINE)=±320 V
Logic input to switch
output isolation
+85° C, VSW (RRINGING, RLINE)=±330 V
0.1
ISW
-
-40° C, VSW (RRINGING, RLINE)= ±310 V
Transient Immunity
100VPP Square Wave, 100Hz
(Not production tested - limits are
guaranteed by design and quality
control sampling audits.)
0.3
0.1
dV/dt
1500
2100
*Secondary protection and current limiting must prevent exceeding this parameter.
R00D
PRELIMINARY
7
CPC7695
1.6.4 TESTout Switches, SW5 and SW6
Parameter
Test Conditions
Symbol
Minimum
Typical
Maximum
Unit
1
μA
VSW5 (differential) = TLINE to TTESTOUT
VSW6 (differential) = RLINE to RTESTOUT
All-Off state.
Off-State
Leakage Current
+25° C,
VSW (differential) = -320 V to gnd
VSW (differential) = +260 V to -60 V
0.1
+85° C
VSW (differential) = -330 V to gnd
VSW (differential) = +260 V to -60 V
ISW
-
-40° C
VSW (differential) = -310 V to gnd
VSW (differential) = +250 V to -60 V
0.3
0.1
ISW (on) = ±10 mA, ±40 mA
On Resistance
+25° C
RON
+85° C
-
35
Ω
50
70
26
-
-
140
-
80
100
-
-
210
250
-
2.5
-
A
1
μA
-
V/μs
-40° C
VSW (on) = ±10 V
DC current limit
+25° C
ISW
+85° C
-40° C
Dynamic current limit
(t ≤ 0.5 μs)
Logic input to switch
output isolation
Test out switches on, all other switches
off. Apply ±1 kV, 10x1000 μs pulse with
appropriate protection in place.
ISW
VSW5 (TTESTout, TLINE)
VSW6 (RTESTout, RLINE)
Logic inputs = GND
+25° C, VSW = ±320 V
0.1
+85° C, VSW = ±330 V
ISW
-
-40° C, VSW = ±310 V
Transient Immunity
8
mA
0.3
0.1
100VPP Square Wave, 100Hz
(Not production tested - limits are
guaranteed by design and quality
control sampling audits.)
dV/dt
PRELIMINARY
1500
2100
R00D
CPC7695
1.6.5 Ringing Test Return Switch, SW7
Parameter
Test Conditions
Symbol
Minimum
Typical
Maximum
Unit
1
μA
VSW7 (differential) = TTESTin to
TRINGING
All-Off state.
Off-State
Leakage Current
+25° C,
VSW (differential) = -320 V to gnd
VSW (differential) = +260 to -60 V
0.1
+85° C,
VSW (differential) = -330 V to gnd
VSW (differential) = +270 V to -60 V
ISW
-
-40° C,
VSW (differential) = -310 V to gnd
VSW (differential) = +250 V to -60 V
0.3
0.1
ISW (on) = ±10 mA, ±40 mA
On Resistance
+25° C
RON
+85° C
-
-40° C
60
-
85
100
45
-
Ω
VSW (on) = ±10 V
DC current limit
+25° C
ISW
+85° C
-40° C
-
120
60
80
-
210
-
mA
1
μA
-
V/μs
Logic inputs = GND
Logic input to switch
output isolation
+25°C, VSW(TRINGING, TTESTin)=±320V
+85°C, VSW(TRINGING, TTESTin)=±330V
0.1
ISW
-
-40°C, VSW(TRINGING, TTESTin)=±310 V
Transient Immunity
R00D
100VPP Square Wave, 100Hz
(Not production tested - limits are
guaranteed by design and quality
control sampling audits.)
0.3
0.1
dV/dt
PRELIMINARY
1500
2100
9
CPC7695
1.6.6 Ringing Test Switch, SW8
Parameter
Test Conditions
Symbol
Minimum
Typical
Maximum
Unit
1
μA
VSW8 (differential) = RTESTin to
RRINGING
All-Off state.
Off-State
Leakage Current
+25° C,
VSW (differential) = -320 V to gnd
VSW (differential) = +320 V to gnd
0.1
+85° C
VSW (differential) = -330 V to gnd
VSW (differential) = +330 V to gnd
ISW
-
-40° C
VSW (differential) = -310 V to gnd
VSW (differential) = +310 V to gnd
0.3
0.1
ISW (on) = ±10 mA, ±40 mA
On Resistance
+25° C
RON
+85° C
-
35
Ω
50
70
26
-
-
140
-
80
100
-
-
210
250
-
2.5
-
A
1
μA
-
V/μs
-40° C
VSW (on) = ±10 V
DC current limit
+25° C
ISW
+85° C
-40° C
Dynamic current limit
(t ≤ 0.5 μs)
Ringing test switches on, all other
switches off. Apply ±1 kV, 10x1000 μs
pulse with appropriate protection in
place.
ISW
mA
VSW8 (RRINGING, RTESTin)
Logic inputs = GND
Logic input to switch
output isolation
+25° C, VSW = ±320 V
0.1
ISW
+85° C, VSW = ±330 V
-
-40° C, VSW = ±310 V
Transient Immunity
10
0.3
0.1
100VPP Square Wave, 100Hz
(Not production tested - limits are
guaranteed by design and quality
control sampling audits.)
dV/dt
PRELIMINARY
1500
2100
R00D
CPC7695
1.6.7 TESTin Switches, SW9 and SW10
Parameter
Test Conditions
Symbol
Minimum
Typical
Maximum
Unit
1
μA
VSW9 (differential) = TTESTin to TBAT
VSW10 (differential) = RTESTin to RBAT
All-Off state.
Off-state leakage
current
+25° C,
VSW (differential) = -320 V to gnd
VSW (differential) = +260 V to -60 V
0.1
+85° C,
VSW (differential) = -330 V to gnd
VSW (differential) =+270 V to -60 V
ISW
-
-40° C,
VSW (differential) = -310 V to gnd
VSW (differential) = +250 V to -60 V
0.3
0.1
ISW (on) = ±10 mA, ±40 mA
On Resistance
+25° C
RON
+85° C
-
35
-
50
70
26
-
-
160
-
80
110
-
-
210
250
-40° C
Ω
VSW (on) = ±10 V
DC current limit
+25° C
ISW
+85° C
-40° C
mA
Logic inputs = GND
Logic input to switch
output isolation
+25°C, VSW(TTESTin, RTESTin) = ±320 V
+85°C, VSW(TTESTin, RTESTin) = ±330 V
0.1
ISW
-
-40°C, VSW (TTESTin, RTESTin) = ±310 V
Transient Immunity
R00D
100VPP Square Wave, 100Hz
(Not production tested - limits are
guaranteed by design and quality
control sampling audits.)
0.3
1
μA
-
V/μs
0.1
dV/dt
PRELIMINARY
1500
2100
11
CPC7695
1.7 Digital I/O Electrical Specifications
Parameter
Test Conditions
Symbol
Minimum
Typical
Maximum
Unit
Input voltage, Logic low
Input voltage falling
VIL
0.8
1.1
-
Input voltage, Logic high
Input voltage rising
VIH
-
1.7
2.0
Input leakage current,
INRINGING, INTESTin,
VDD = 5.5 V, VBAT = -75 V, VIH = 2.4V
and INTESTout Logic high
IIH
-
0.1
1
μA
Input leakage current,
INRINGING, INTESTin,
VDD = 5.5 V, VBAT = -75 V, VIL = 0.4V
and INTESTout Logic low
IIL
-
0.1
1
μA
Input leakage current,
LATCH Logic high
VDD = 4.5 V, VBAT = -75 V, VIH = 2.4V
IIH
10
19
-
μA
Input leakage current,
LATCH Logic low
VDD = 5.5 V, VBAT = -75 V, VIL = 0.4V
IIL
-
47
125
μA
Input leakage current,
TSD Logic high
VDD = 5.5 V, VBAT = -75 V, VIH = VDD
IIH
10
16
30
μA
Input leakage current,
TSD Logic low
VDD = 5.5 V, VBAT = -75 V, VIL = 0.4V
IIL
10
16
30
μA
Input Characteristics
V
Output Characteristics
Output voltage,
TSD Logic high
VDD = 5.5 V, VBAT = -75 V, ITSD = 10μA
VTSD_off
2.4
VDD
-
V
Output voltage,
TSD Logic low
VDD = 5.5 V, VBAT = -75 V, ITSD = 1mA
VTSD_on
-
0
0.4
V
12
PRELIMINARY
R00D
CPC7695
1.8 Voltage and Power Specifications
Parameter
Test Conditions
Symbol
Minimum
Typical
Maximum
Unit
Voltage Requirements
VDD
-
VDD
4.5
5.0
5.5
V
VBAT1
-
VBAT
-19
-48
-72
V
1
VBAT is used only for internal protection circuitry. If VBAT rises above-10 V, the device will enter the all-off state and will remain in the all-off state until the battery
drops below -15 V
Power Specifications
Power consumption
VDD = 5 V, VBAT = -48 V, VIH = 2.4V,
VIL = 0.4V, Measure IDD and IBAT,
Talk and All-Off States
All other states
VDD current in talk and
VDD = 5 V, VBAT = -48 V, VIH = 2.4V,
all-off states
VDD current in all other VIL = 0.4V
states
V = 5V, VBAT = -48 V, VIH = 2.4V,
VBAT current in any state DD
VIL = 0.4V
P
P
-
4.7
5.2
10.5
10.5
IDD
-
0.9
2.0
mW
mW
mA
IDD
-
1.0
2.0
IBAT
-
4
10
μA
Symbol
Minimum
Typical
Maximum
Unit
VF
-
2.8
3.5
1.9 Protection Circuitry Electrical Specifications
Parameter
Conditions
Protection Diode Bridge
Forward Voltage drop,
Apply ± dc current limit of break
continuous current
switches
(50/60 Hz)
Forward Voltage drop, Apply ± dynamic current limit of break
surge current
switches
Protection SCR (CPC7695xA and CPC7695xC)
Surge current
SCR activates, +25° C
Trigger current:
Current into VBAT pin. SCR activates, +85° C
SCR remains active, +25° C
Hold current: Current
through protection SCR SCR remains active, +85° C
Gate trigger voltage
IGATE = ITRIGGER§
Reverse leakage current VBAT = -48 V
0.5 A, t = 0.5 μs
On-state voltage
2.0 A, t = 0.5 μs
Temperature Shutdown Specifications
Shutdown activation
Not production tested - limits are
temperature
guaranteed by design and Quality
Shutdown circuit
Control sampling audits.
hysteresis
V
VF
-
5
-
-
-
*
A
ITRIG
-
-
mA
IHOLD
110
150
80
220
145
-
mA
VTBAT or
VRBAT
VBAT -4
-
VBAT -2
V
IVBAT
-
-
1.0
μA
VTBAT or
VRBAT
-
-3
-5
-
V
TTSD_on
110
125
150
°C
TTSD_off
10
-
25
°C
*Passes GR1089 and ITU-T K.20 with appropriate secondary protection in place.
§V
BAT must be capable of sourcing ITRIGGER for the internal SCR to activate.
R00D
PRELIMINARY
13
CPC7695
1.10 Truth Tables
1.10.1 Truth Table for CPC7695xA and CPC7695xB
TESTin
Switches
Break
Switches
Ringing
Test
Switches
Ringing
Switches
TESTout
Switches
0
Off
On
Off
Off
Off
0
1
Off
Off
Off
Off
On
0
1
0
On
Off
Off
Off
Off
Simultaneous
TESTin and
TESTout
0
1
1
On
Off
Off
Off
On
Ringing
1
0
0
Off
Off
Off
On
Off
Ringing
Generator
Test
1
1
0
Off
Off
On
Off
Off
Latched
X
X
X
1
1
0
1
0
Off
Off
Off
Off
Off
1
1
1
0
Off
Off
Off
Off
Off
X
X
X
X
Off
Off
Off
Off
Off
TESTout
Switches
State
INRINGING
INTESTin
INTESTout
Talk
0
0
TESTout
0
TESTin
All-Off
1
Latch
TSD
0
Z1
Unchanged Unchanged Unchanged Unchanged Unchanged
0
Z = High Impedance. Because TSD has an internal pull up at this pin, it should be controlled with an open-collector or open-drain type device.
1.10.2 Truth Table for CPC7695xC
State
INRINGING
INTESTin
INTESTout
Latch
TSD
TESTin
Switches
Break
Switches
Ringing
Test
Switches
Ringing
Switches
Talk
0
0
0
Off
On
Off
Off
Off
TESTout
0
0
1
Off
Off
Off
Off
On
TESTin
0
1
0
On
Off
Off
Off
Off
Simultaneous
TESTin and
TESTout
0
1
1
On
Off
Off
Off
On
Off
Off
Off
On
Off
Off
Off
On
Off
Off
Off
Off
On
Off
On
Ringing
1
0
0
Ringing
Generator
Test
1
1
0
Simultaneous
TESTout and
Ringing
Generator
Test
1
1
1
Latched
X
X
X
All-Off
1
0
Z1
1
1
0
1
0
X
X
X
X
Unchanged Unchanged Unchanged Unchanged Unchanged
0
Off
Off
Off
Off
Off
Off
Off
Off
Off
Off
Z = High Impedance. Because TSD has an internal pull up at this pin, it should be controlled with an open-collector or open-drain type device.
14
PRELIMINARY
R00D
CPC7695
2. Functional Description
2.1 Introduction
The CPC7695 has the following states:
• Talk. Loop break switches SW1 and SW2 closed, all
other switches open.
• Ringing. Ringing switches SW3 and SW4 closed, all
other switches open.
• TESTout. Testout switches SW5 and SW6 closed,
all other switches open.
• Ringing generator test. SW7 and SW8 closed, all
other switches open.
• TESTin. Testin switches SW9 and SW10 closed, all
other switches open.
• Simultaneous TESTin and TESTout. SW9, SW10,
SW5, and SW6 closed, all other switches open.
• Simultaneous TESTout and Ringing generator
test. SW5, SW6, SW7, and SW8 closed, all other
switches open (only on the xC and xD versions).
• All-Off. All switches open.
See “Truth Tables” on page 14 for more information.
The CPC7695 offers break-before-make and
make-before-break switching from the ringing state to
the talk state with simple TTL level logic input control.
Solid-state switch construction means no impulse
noise is generated when switching during ringing
cadence or ring trip, eliminating the need for external
zero-cross switching circuitry. State-control is via TTL
logic-level input so no additional driver circuitry is
required. The linear line break switches SW1 and
SW2 have exceptionally low RON and excellent
matching characteristics. The ringing switch, SW4,
has a minimum open contact breakdown voltage of
465 V at +25°C, sufficiently high with proper protection
to prevent breakdown in the presence of a transient
fault condition (i.e., passing the transient on to the
ringing generator).
Integrated into the CPC7695 is an over-voltage
clamping circuit, active current limiting, and a thermal
shutdown mechanism to provide protection to the
SLIC during a fault condition. Positive and negative
lightning surge currents are reduced by the current
limiting circuitry and hazardous potentials are diverted
away from the SLIC via the protection diode bridge or
the optional integrated protection SCR. Power-cross
potentials are also reduced by the current limiting and
thermal shutdown circuits.
R00D
To protect the CPC7695 from an overvoltage fault
condition, the use of a secondary protector is required.
The secondary protector must limit the voltage seen at
the TLINE and RLINE terminals to a level below the
maximum breakdown voltage of the switches. To
minimize the stress on the solid-state contacts, use of
a foldback or crowbar type secondary protector is
highly recommended. With proper selection of the
secondary protector, a line card using the CPC7695
will meet all relevant ITU, LSSGR, TIA/EIA and IEC
protection requirements.
The CPC7695 operates from a single +5 V supply
only. This gives the device extremely low idle and
active power consumption with virtually any range of
battery voltage. The battery voltage used by the
CPC7695 has a two fold function. For protection
purposes it is used as a fault condition current source
for the internal integrated protection circuitry.
Secondly, it is used as a reference so that in the event
of battery voltage loss, the CPC7695 will enter the
all-off state.
2.2 Under Voltage Switch Lock Out Circuitry
2.2.1 Introduction
Smart logic in the CPC7695 now provides for switch
state control during both power up and power loss
transitions. An internal detector is used to evaluate the
VDD supply to determine when to de-assert the under
voltage switch lock out circuitry with a rising VDD and
when to assert the under voltage switch lock out
circuitry with a falling VDD. Any time unsatisfactory low
VDD conditions exist, the lock out circuit overrides user
switch control by blocking the information at the
external input pins and conditioning internal switch
commands to the all-off state. Upon restoration of
VDD, the switches will remain in the all-off state until
the LATCH input is pulled low.
The rising VDD switch lock-out release threshold is
internally set to ensure all internal logic is properly
biased and functional before accepting external switch
commands from the inputs to control the switch states.
For a falling VDD event, the lock-out threshold is set to
assure proper logic and switch behavior up to the
moment the switches are forced off and external
inputs are suppressed.
PRELIMINARY
15
CPC7695
To facilitate hot plug insertion and system power up
state control, the LATCH pin has an integrated weak
pull up resistor to the VDD power rail that will hold a
non-driven LATCH pin at a logic high state. This
enables board designers to use the CPC7695 with
FPGAs and other devices that provide high
impedance outputs during power up and logic
configuration. The weak pull up allows a fan out of up
to 32 when the system’s LATCH control driver has a
logic low minimum sink capability of 4mA.
2.2.2 Hot Plug and Power Up Circuit Design
Considerations
All inputs defined at power up & LATCH = 0
All inputs defined at power up & LATCH = 1
All inputs defined at power up & LATCH = Z
All inputs not defined at power up & LATCH = 0
All inputs not defined at power up & LATCH = 1
All inputs not defined at power up & LATCH = Z
Under all of the start up situations listed above the
CPC7695 will hold all of it’s switches in the all-off state
during power up. When VDD requirements have been
satisfied the LCAS will complete it’s start up procedure
in one of three conditions.
For start up scenario 1 the CPC7695 will transition
from the all-off state to the state defined by the inputs
when VDD is valid.
For start up scenarios 2, 3, 5, and 6 the CPC7695 will
power up in the all-off state and remain there until the
LATCH pin is pulled low. This allows for an indefinite
all-off state for boards inserted into a powered system
but are not configured for service or boards that need
to wait for other devices to be configured first.
Start up scenario 4 will start up with all switches in the
all-off state but upon the acceptance of a valid VDD the
LCAS will revert to any one of the legitimate states
listed in the truth tables and there after may randomly
change states based on input pin leakage currents
and loading. Because the LCAS state after power up
can not be predicted with this start up condition it
should never be utilized.
On designs that do not wish to individually control the
LATCH pins of multi-port cards it is possible to bus
many (or all) of the LATCH pins together to create a
single board level input enable control.
16
2.3.1 Start-up
The CPC7695 uses smart logic to monitor the VDD
supply. Any time the VDD is below an internally set
threshold, the smart logic places the control logic to
the all-off state. An internal pullup on the LATCH pin
locks the CPC7695 in the all-off state following
start-up until the LATCH pin is pulled down to a logic
low. Prior to the assertion of a logic low at the LATCH
pin, the switch control inputs must be properly
conditioned.
2.3.2 Switch Timing
There are six possible start up scenarios that can
occur during power up. They are:
1.
2.
3.
4.
5.
6.
2.3 Switch Logic
The CPC7695 provides, when switching from the
ringing state to the talk state, the ability to control the
release timing of the ringing switches SW3 and SW4
relative to the state of the break switches SW1 and
SW2 using simple TTL logic-level inputs. The two
available techniques are referred to as
make-before-break and break-before-make operation.
When the switch contacts of SW1 and SW2 are closed
(made) before the ringing switch contacts of SW3 and
SW4 are opened (broken), this is referred to as
make-before-break operation. Break-before-make
operation occurs when the ringing contacts of SW3
and SW4 are opened (broken) before the switch
contacts of SW1 and SW2 are closed (made). With
the CPC7695, make-before-break and
break-before-make operations can easily be
accomplished by applying the proper sequence of
logic-level inputs to the device.
The logic sequences for either mode of operation are
given in “Make-Before-Break Operation Logic Table
(Ringing to Talk Transition)” on page 17,
“Break-Before-Make Operation Logic Table (Ringing to Talk
Transition)” on page 17 and “Alternate Break-Before-Make
Operation Logic Table (Ringing to Talk Transition)” on
page 18. Logic states and explanations are shown in
“Truth Tables” on page 14.
2.3.3 Make-Before-Break Operation
To use make-before-break operation, change the logic
inputs from the ringing state directly to the talk state.
Application of the talk state opens the ringing return
switch, SW3, as the break switches SW1 and SW2
close. The ringing switch, SW4, remains closed until
the next zero-crossing of the ringing current. While in
the make-before-break state, ringing potentials in
excess of the CPC7695 protection circuitry thresholds
will be diverted away from the SLIC.
PRELIMINARY
R00D
CPC7695
Make-Before-Break Operation Logic Table (Ringing to Talk Transition)
State
INRINGING INTESTin INTESTout
Ringing
1
0
0
MakeBeforeBreak
0
0
0
Talk
0
0
0
Latch
0
TSD
Timing
Z
SW4 waiting for next
zero-current crossing to turn
off. Maximum time is one-half
of the ringing cycle. In this
transition state, current that is
limited to the break switch dc
current limit value will be
sourced from the ring node of
the SLIC.
Zero-cross current has
occurred
Ringing
Ringing
Return
Break
Test
Switch
Switches Switch
Switches
(SW4)
(SW3)
Off
On
On
Off
On
Off
On
Off
On
Off
Off
Off
Break-before-make operation of the CPC7695 can be
achieved using two different techniques.
2. Hold the all-off state for at least one-half of a
ringing cycle to assure that a zero crossing event
occurs and that the ringing switch (SW4) has
opened.
The first method uses manipulation of the (INRINGING,
INTESTin, INTESTout) logic inputs as shown in
“Break-Before-Make Operation Logic Table (Ringing to Talk
Transition)” on page 17.
3. Apply inputs for the next desired state. For the
talk state, the inputs would be (0,0,0).
2.3.4 Break-Before-Make Operation
1. At the end of the ringing state apply the all-off
state (1,0,1). This releases the ringing return
switch (SW3) while the ringing switch remains on
waiting for the next zero current event.
Break-before-make operation occurs when the ringing
switch opens before the break switches SW1 and
SW2 close.
Break-Before-Make Operation Logic Table (Ringing to Talk Transition)
State
INRINGING INTESTin INTESTout
Ringing
1
0
0
All-off *
1
0
1
Latch
0
BreakBeforeMake *
Talk
TSD
Timing
Z
Hold this state for at least
one-half of ringing cycle.
SW4 waiting for zero current
to turn off.
Ringing
Ringing
Return
Break
Test
Switch
Switches Switch
Switches
(SW4)
(SW3)
Off
On
On
Off
Off
Off
On
Off
1
0
1
Zero current has occurred.
SW4 has opened
Off
Off
Off
Off
0
0
0
Break switches close.
On
Off
Off
Off
* For the CPC7695xA/B versions the input pattern (1,1,1) may also be used for the all-off state.
2.3.5 Alternate Break-Before-Make Operation
The second break-before-make method is also
available for use with all versions of the CPC7695. As
R00D
shown in “Truth Table for CPC7695xA and CPC7695xB” on
page 14 and “Truth Table for CPC7695xC” on page 14, the
bidirectional TSD interface disables all of the CPC7695
PRELIMINARY
17
CPC7695
switches when pulled to a logic low. Although logically
disabled, an active (closed) ringing switch (SW4) will
remain closed until the next current zero crossing
event.
As shown in the table “Break-Before-Make Operation
Logic Table (Ringing to Talk Transition)” on page 17, this
operation is similar to the one shown in “Alternate
Break-Before-Make Operation Logic Table (Ringing to Talk
Transition)” on page 18, except in the method used to
select the all-off state and when the INRINGING,
INTESTin and INTESTout inputs are reconfigured for the
talk state.
1. Pull TSD to a logic low to end the ringing state.
This opens the ringing return switch (SW3) and
prevents any other switches from closing.
2. Keep TSD low for at least one-half the duration of
the ringing cycle period to allow sufficient time for
a zero crossing current event to occur and for the
circuit to enter the break before make state.
3. During the TSD low period, set the INRINGING,
INTESTin and INTESTout inputs to the talk state
(0,0,0).
4. Release TSD allowing the internal pull-up to
activate the break switches.
When using TSD as an input, the two recommended
states are “0” which over rides logic input pins and
forces an all-off state and “Z” which allows switch
control via the logic input pins. This requires the use of
an open-collector or open-drain type buffer.
Alternate Break-Before-Make Operation Logic Table (Ringing to Talk Transition)
State
INRINGING INTESTin INTESTout
Ringing
1
0
0
All-off
1
0
1
Latch
TSD
Timing
0
Z
Hold this state for at least
one-half of ringing cycle.
SW4 waiting for zero current
to turn off.
X
BreakBeforeMake
Talk
0
0
0
0
0
0
0
0
Z
Ringing
Ringing
Return
Break
Test
Switch
Switches Switch
Switches
(SW4)
(SW3)
Off
On
On
Off
Off
Off
On
Off
Zero current has occurred.
SW4 has opened
Off
Off
Off
Off
Break switches close.
On
Off
Off
Off
* For the CPC7695xA/B versions the input pattern (1,1,1) may also be used for the all-off state.
2.4 Data Latch
The CPC7695 has an integrated transparent data
latch. The latch enable operation is controlled by TTL
logic input levels at the LATCH pin. Data input to the
latch are via the input pins, while the output of the data
latch are internal nodes used for state control. When
the LATCH enable control pin is at logic 0 the data
latch is transparent and the input data control signals
flow directly through the latch to the state control
circuitry. A change in input will be reflected by a
change in switch state. Whenever the LATCH enable
control pin is at logic 1, the latch is active and data is
locked. Subsequent input changes will not result in a
change to the control logic or affect the existing switch
state.
18
Switches will remain in the state they were in when the
LATCH pin changes from logic 0 to logic 1 and will not
respond to changes in input as long as the latch is at
logic 1. However, neither the TSD input nor the TSD
output control functions are affected by the latch
function. Internal thermal shutdown control and
external “All-off” control via TSD is not affected by the
state of the LATCH enable input.
2.5 TSD Pin Description
The TSD pin is a bi-directional I/O structure with an
internal pull up sourced from VDD. As an output, this
pin indicates the status of the thermal shutdown
circuitry. Typically, during normal operation, this pin will
be pulled up to VDD but under fault conditions that
create excess thermal loading the CPC7695 will enter
thermal shutdown and a logic low will be output.
PRELIMINARY
R00D
CPC7695
As an input, the TSD pin can be utilized to place the
CPC7695 into the “All-Off” state by simply pulling the
input low via an open-collector type buffer. Using a
standard output with an active logic high drive
capability will sink the pull-up current resulting in
unnecessary power consumption.
net supplying this current be a low impedance path for
high speed transients such as lightning. This will
permit trigger currents to flow enabling the SCR to
activate and thereby prevent a fault induced negative
overvoltage event at the TBAT or RBAT nodes.
Use of a standard output buffer with an active high
drive capability will not disable the thermal shutdown
mechanism. The ability to enter thermal shutdown
during a fault condition is independent of the
connection at the TSD input.
2.8 Battery Voltage Monitor
The CPC7695 also uses the VBAT pin to monitor
battery voltage. If the system battery voltage is lost,
the CPC7695 immediately enters the all-off state. It
remains in this state until the system battery voltage is
restored. The device also enters the all-off state if the
battery voltage rises more positive than about –10 V
and remains in the all-off state until the battery voltage
drops below –15 V. This battery monitor feature draws
a small current from the battery (less than 1 μA
typical) and will add slightly to the device’s overall
power dissipation.
The CPC7695’s internal pull up has a nominal value of
16μA.
2.6 Ringing Switch Zero-Cross Current Turn Off
After the application of a logic input to turn SW4 off,
the ringing switch is designed to delay the change in
state until the next zero-crossing. Once on, the switch
requires a zero-current cross to turn off, and therefore
should not be used to switch a pure DC signal. The
switch will remain in the on state no matter the logic
input until the next zero crossing. These switching
characteristics will reduce and possibly eliminate
overall system impulse noise normally associated with
ringing switches. See Clare application note AN-144,
Impulse Noise Benefits of Line Card Access Switches for
more information. The attributes of ringing switch SW4
may make it possible to eliminate the need for a
zero-cross switching scheme. A minimum impedance
of 300 Ω in series with the ringing generator is
recommended.
2.7 Power Supplies
Both a +5 V supply and battery voltage are connected
to the CPC7695. Switch state control is powered
exclusively by the +5 V supply. As a result, the
CPC7695 exhibits extremely low power consumption
during active and idle states.
Although battery power is not used for switch control, it
is required to supply trigger current for the integrated
internal protection circuitry SCR during fault
conditions. This integrated SCR is designed to
activate whenever the voltage at TBAT or RBAT drops 2
to 4 V below the applied voltage on the VBAT pin.
Because the battery supply at this pin is required to
source trigger current during negative overvoltage
fault conditions at tip and ring, it is important that the
R00D
This monitor function performs properly if the
CPC7695 and SLIC share a common battery supply
origin. Otherwise, if battery is lost to the CPC7695 but
not to the SLIC, the VBAT pin will be internally biased
by the potential applied to the TBAT or RBAT pins via
the internal protection circuitry SCR trigger current
path.
2.9 Protection
2.9.1 Diode Bridge/SCR
The CPC7695 uses a combination of current limited
break switches, a diode bridge/SCR clamping circuit,
and a thermal shutdown mechanism to protect the
SLIC device or other associated circuitry from damage
during line transient events such as lightning. During a
positive transient condition, the fault current is
conducted through the diode bridge to ground via
FGND. Voltage is clamped to a diode drop above
ground. During a negative transient of 2 to 4 V more
negative than the voltage source at VBAT, the SCR
conducts and faults are shunted to FGND via the SCR
or the diode bridge.
In order for the SCR to crowbar or foldback, the SCR’s
on-voltage (see “Protection Circuitry Electrical
Specifications” on page 13) must be less than the
applied voltage at the VBAT pin. If the VBAT voltage is
less negative than the SCR on-voltage, or if the VBAT
supply is unable to source the trigger current, the SCR
will not crowbar.
PRELIMINARY
19
CPC7695
For power induction or power-cross fault conditions,
the positive cycle of the transient is clamped to a diode
drop above ground and the fault current is directed to
ground. The negative cycle of the transient will cause
the SCR to conduct when the voltage exceeds the
VBAT reference voltage by two to four volts, steering
the fault current to ground.
Note: The CPC7695xB does not contain a protection
SCR but instead utilizes a diode bridge to clamp both
polarities of a fault transient. These diodes pass the
charge of negative fault potentials to the VBAT pin.
2.9.2 Current Limiting function
If a lightning strike transient occurs when the device is
in the talk state, the current is passed along the line to
the integrated protection circuitry and restricted by the
dynamic current limit response of the active switches.
During the talk state when a 1000V 10x1000 μS pulse
(GR-1089-CORE lightning) is applied to the line
though a properly clamped external protector, the
current seen at TLINE or RLINE will be a pulse with a
typical magnitude of 2.5 A and a duration of less than
0.5 μs.
If a power-cross fault occurs with the device in the talk
state, the current is passed though the break switches
SW1 and SW2 on to the integrated protection circuit
but is limited by the dynamic DC current limit response
of the two break switches. The DC current limit
specified over temperature is between 80 mA and
425 mA, and the circuitry has a negative temperature
coefficient. As a result, if the device is subjected to
extended heating due to a power cross fault condition,
the measured current into TLINE or RLINE will decrease
as the device temperature increases. If the device
temperature rises sufficiently, the temperature
shutdown mechanism will activate and the device will
enter the all-off state.
If presented with a short duration transient such as a
lightning event, the thermal shutdown feature will
typically not activate. But in an extended power-cross
event, the device temperature will rise and the thermal
shutdown mechanism will activate forcing the switches
to the all-off state. At this point the current measured
into TLINE or RLINE will drop to zero. Once the device
enters thermal shutdown it will remain in the all-off
state until the temperature of the die drops below the
deactivation level of the thermal shutdown circuit. This
permits the device to return to normal operation. If the
transient has not passed, current will again flow up to
the value allowed by the dynamic DC current limiting
of the switches and heating will resume, reactivating
the thermal shutdown mechanism. This cycle of
entering and exiting the thermal shutdown mode will
continue as long as the fault condition persists. If the
magnitude of the fault condition is great enough, the
external secondary protector will activate shunting the
fault current to ground.
2.11 External Protection Elements
The CPC7695 requires only over voltage secondary
protection on the loop side of the device. The
integrated protection feature described above negates
the need for additional external protection on the SLIC
side. The secondary protector must limit voltage
transients to levels that do not exceed the breakdown
voltage or input-output isolation barrier of the
CPC7695. A foldback or crowbar type protector is
recommended to minimize stresses on the CPC7695.
Consult Clare’s application note, AN-100, “Designing
Surge and Power Fault Protection Circuits for Solid
State Subscriber Line Interfaces” for equations related
to the specifications of external secondary protectors,
fused resistors and PTCs.
2.10 Thermal Shutdown
The thermal shutdown mechanism will activate when
the device die temperature reaches a minimum of
110° C, placing the device in the all-off state
regardless of INRINGING, INTESTin and INTESTout logic
inputs. During thermal shutdown events the TSD pin
will output a logic low with a nominal 0 V level. A logic
high is output from the TSD pin during normal
operation with a typical output level equal to VDD.
20
PRELIMINARY
R00D
CPC7695
3. Manufacturing Information
3.1 Mechanical Dimensions and PCB Land Patterns
3.1.1 CPC7695Z
20-Lead SOIC Package
Recommended PCB Land Pattern
0.23 / 0.32
(0.009 / 0.013)
12.60 / 13.00
(0.496 / 0.512)
0.40 / 1.27
(0.016 / 0.050)
10.00 / 10.65
(0.394 / 0.419)
7.40 / 7.60
(0.291 / 0.299)
Pin 1
2.05
(0.081)
9.30
(0.366)
0.25 / 0.75 x 45º
(0.010 / 0.029 x 45º)
0.508 / 0.762
(0.020 / 0.030)
1.27 TYP
(0.050 TYP)
0.33 / 0.51
(0.013/ 0.020)
2.35 / 2.65
(0.093 / 0.104)
1.27
(0.05)
0º - 8º
0.60
(0.024)
Dimensions
mm MIN / mm MAX
(inches MIN / inches MAX)
0.10 / 0.30
(0.004 / 0.012)
3.1.2 CPC7695B
28-Lead SOIC Package
Recommended PCB Land Pattern
0.2311 / 0.3175
(0.0091 / 0.0125)
17.983 / 18.085
(0.708 / 0.712)
10.109 / 10.516
(0.398 / 0.414)
7.391 / 7.595
(0.291 / 0.299)
Pin 1
R00D
1.80
(0.071)
9.50
(0.374)
0.254 / 0.737 x 45º
(0.010 / 0.029 x 45º)
2.438 / 2.642
(0.096 / 0.104)
1.27 TYP
(0.050 TYP)
0.508 / 1.016
(0.020 / 0.040)
0.366 / 0.467
(0.014/ 0.018)
2.235 / 2.438
(0.088 / 0.096)
0.660 ± 0.102
(0.026 ± 0.004)
PRELIMINARY
1.27
(0.05)
0.60
(0.024)
Dimensions
mm MIN / mm MAX
(inches MIN / inches MAX)
21
CPC7695
3.2 Tape and Reel Specifications
3.2.1 CPC7695Z
P=12.00
(0.47)
330.2 DIA.
(13.00 DIA)
Top Cover
Tape Thickness
0.102 MAX
(0.004 MAX)
B0=13.40 +0.15
(0.53+0.01)
K0=3.20 +0.15
(0.13+0.01)
Embossed Carrier
Embossment
A0=10.75 +0.15
(0.42+0.01)
K1=2.60 +0.15
(0.10+0.01)
W=24.00+0.3
(0.94+0.01)
Dimensions
mm
(inches)
3.2.2 CPC7695B
330.2 DIA.
(13.00 DIA)
Top Cover
Tape Thickness
0.102 MAX
(0.004 MAX)
K1=2.60
(0.10)
K0=3.20
(0.13)
A0=10.75
(0.42)
B0=18.50
(0.73)
W=24.00±0.3
(0.94±0.01)
Embossed Carrier
Embossment
22
P=12.00
(0.47)
PRELIMINARY
Dimensions
mm
(inches)
R00D
CPC7695
3.3 Soldering
For proper assembly, the component must be
processed in accordance with the current revision of
IPC/JEDEC standard, J-STD-020. Failure to follow the
recommended guidelines may cause permanent
damage to the device resulting in impaired
performance and/or a reduced lifetime expectancy.
3.4 Washing
Clare does not recommend ultrasonic cleaning of this
part.
Pb
RoHS
2002/95/EC
e3
For additional information please visit www.clare.com
Clare, Inc. makes no representations or warranties with respect to the accuracy or completeness of the contents of this publication and reserves the right to make
changes to specifications and product descriptions at any time without notice. Neither circuit patent licenses or indemnity are expressed or implied. Except as set
forth in Clare’s Standard Terms and Conditions of Sale, Clare, Inc. assumes no liability whatsoever, and disclaims any express or implied warranty relating to its
products, including, but not limited to, the implied warranty of merchantability, fitness for a particular purpose, or infringement of any intellectual property right.
The products described in this document are not designed, intended, authorized, or warranted for use as components in systems intended for surgical implant into
the body, or in other applications intended to support or sustain life, or where malfunction of Clare’s product may result in direct physical harm, injury, or death to a
person or severe property or environmental damage. Clare, Inc. reserves the right to discontinue or make changes to its products at any time without notice.
Specification: DS-CPC7695-R00D
© Copyright 2009, Clare, Inc.
All rights reserved. Printed in USA.
10/14/09
R00D
PRELIMINARY
23