19-3798; Rev 0; 09/06
Integrated T1/E1/J1 Short-Haul and
Long-Haul Protection Switch
The MAX4670 is an integrated T1/E1/J1 analog protection switch for 1+1 and N+1 line-card redundancy
applications. It protects two T1/E1/J1 ports by combining eight SPDT switches in a single package. The
switch is optimized for high-return loss and pulse-template performance in T1/E1/J1 long-haul and short-haul
applications. The part offers built-in chip-side surge
protection capability for short-haul intrabuilding applications.
The MAX4670 replaces two diode arrays or two transient voltage suppressors (TVSs) and four dual-SPDT
relays, significantly reducing board space and simplifying PC board routing. The MAX4670 pinout is targeted
for T1/E1/J1 applications, resulting in a simplified layout
when interfacing with standard line transformers and
line interface units (LIUs).
The MAX4670 has four 1.0Ω (max) on-resistance switches with 60pF/40pF on-/off-capacitances for interfacing to
the LIU transmitter outputs. The MAX4670 also includes
four 10Ω (max) on-resistance switches with low
24pF/12pF on-/off-capacitances for interfacing to the LIU
receiver inputs. Four logic inputs control the receive/
transmit pairs, in addition to a SWITCH input that connects all switches to the system’s protection bus.
The MAX4670 operates from a single +2.7V to +3.6V
supply and is available in 32-pin thermally enhanced
TQFN package. The MAX4670 is specified over the
-40°C to +85°C operating temperature range.
Features
♦ Single +3.3V Supply Voltage
♦ Quad-DPDT/Octal-SPDT Switches Support
Two T1/E1/J1 Ports
♦ Low RON
♦ 0.7Ω (typ) in Transmit Path; 5Ω (typ) in
Receive Path
♦ Low CON/COFF
60pF/40pF (typ) in Transmit Path
24pF/12pF (typ) in Receive Path
♦ Chip Surge Protection
IEC 61000-4-5 (8µs to 20µs Surge)
Class 2 (±1kV)
♦ -70dB (typ) Crosstalk/Off-Isolation (3MHz)
♦ Small, 32-Pin TQFN Package
Ordering Information
PINPACKAGE
PART*
SURGE
PROTECTION
PKG
CODE
YES
T3255-4
32 TQFN
(5mm x 5mm)
MAX4670ETJ
*This part operates at a -40°C to +85°C temperature range.
Pin Configuration
Applications
17 NO6
18 NC6
19 NO5
20 NC5
21 NO4
Multiservice Switches
22 NC4
TOP VIEW
24 NC3
Edge Routers
23 NO3
Optical Multiplexers (ADMs, M13s, etc.)
Base Station Controllers (Wireless Infrastructure
Equipment)
NO2
25
16
NC7
NC2
26
15
NO7
Media Gateways (VoIP)
NO1
27
14
NC8
NC1
28
13
NO8
12
COM8
COM1
29
COM2
30
11
COM7
INA
31
10
IND
V+
32
9
V+
SWITCH 8
COM6 7
COM5 6
INC 5
GND 4
COM4 3
*NOTE:
EXPOSED PADDLE
CONNECTED TO GND
COM3 2
*EP
INB 1
Functional Diagram/Truth Table appears at end of data sheet.
MAX4670
TQFN
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
1
MAX4670
General Description
MAX4670
Integrated T1/E1/J1 Short-Haul and
Long-Haul Protection Switch
ABSOLUTE MAXIMUM RATINGS
(All voltages referenced to GND.)
V+, IN_, SWITCH ......................................................-0.3V to +4V
COM_, NO_, NC_ (Note 1) ...........................-0.3V to (V+ + 0.3V)
Continuous Current
NO_, NC_, COM_ (Tx interface)..................................±150mA
NO_, NC_, COM_ (Rx interface) .................................±100mA
Peak Currents
NO_, NC_, COM_ (Tx interface)
(pulsed at 1ms, 10% duty cycle) ................................±300mA
NO_, NC_, COM_ (Rx interface)
(pulsed at 1ms, 10% duty cycle) ................................±200mA
Peak Surge Currents
Poised at 8µs ..................................................................21.4A
Poised at 20µs ................................................................11.9A
Continuous Power Dissipation (TA = +70°C)
32-Pin TQFN (derate 21.3mW/°C above +70°C) .......1702mW
38-Pin TSSOP (derate 13.7mW/°C above +70°C) .....1096mW
Operating Temperature Range ...........................-40°C to +85°C
Storage Temperature Range .............................-65°C to +150°C
Junction Temperature ......................................................+150°C
Lead Temperature (soldering, 10s) .................................+300°C
Note 1: Signals on NO_, NC_, COM_ exceeding V+ or GND are clamped by internal diodes. Limit forward-diode current to maximum
current rating.
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(V+ = +2.7V to +3.6V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C, unless otherwise noted.) (Notes 2, 3)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
5
9
UNITS
Rx INTERFACE
On-Resistance
On-Resistance Match Between
Channels (Note 4)
On-Resistance Flatness (Note 4)
RON
V+ = 3V, ICOM_ = 10mA,
VNO_ or VNC_ = 1.5V
TA = +25°C
TA = TMIN to TMAX
10
∆RON
V+ = 3V, ICOM_ = 10mA,
VNO_ or VNC_ = 1.5V
TA = +25°C
1.0
TA = TMIN to TMAX
1.3
V+ = 3V; ICOM_ = 10mA;
VNO_ or VNC_ = 1.0V,
1.5V, 2.0V
TA = +25°C
RFLAT(ON)
INO(OFF)
NO_ or NC_ Off-Leakage
Current
INC (OFF)
COM_ On-Leakage Current
ICOM(ON)
2.0
Ω
Ω
3.0
Ω
TA = TMIN to TMAX
3.4
V+ = 3.6V; VCOM_ = 0.3V, 3.3V;
VNO_ or VNC_ = 3.3V, 0.3V
-1
+1
µA
V+ = 3.6V; VCOM_ = 0.3V, 3.3V;
VNO_ or VNC_ = 3.3V, 0.3V or floating
-1
+1
µA
Tx INTERFACE
On-Resistance (Note 5)
On-Resistance Match Between
Channels (Notes 3, 5)
On-Resistance Flatness
(Notes 5, 6)
2
RON
∆RON
RFLAT(ON)
V+ = 3V, ICOM_ = 100mA, TA = +25°C
VNO_ or VNC_ = 1.5V
TA = TMIN to TMAX
T
V+ = 3V, ICOM_ = 100mA, A = +25°C
VNO_ or VNC_ = 1.5V
TA = TMIN to TMAX
V+ = 3V;
ICOM_ = 100mA;
VNO_ or VNC_ = 1.0V,
1.5V, 2.0V
TA = +25°C
0.7
0.9
1.0
0.03
0.150
0.175
0.1
Ω
Ω
0.18
Ω
TA = TMIN to TMAX
_______________________________________________________________________________________
0.2
Integrated T1/E1/J1 Short-Haul and
Long-Haul Protection Switch
(V+ = +2.7V to +3.6V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C, unless otherwise noted.) (Notes 2, 3)
PARAMETER
SYMBOL
CONDITIONS
NO_ or NC_ Off-Leakage
Current
INO(OFF),
INC(OFF)
V+ = 3.6V; VCOM_ = 0.3V, 3.3V;
VNO_ or VNC_ = 0.3V, 3.3V
COM_ On-Leakage Current
ICOM(ON)
V+ = 3.6V; VCOM_ = 0.3V, 3.3V;
VNO_ or VNC_ = 0.3V, 3.3V or floating
MIN
TYP
MAX
UNITS
-1
+1
µA
-1
+1
µA
DYNAMIC CHARACTERISTICS
Turn-On Time
tON
Turn-Off Time
tOFF
Break-Before-Make Delay
tD
VNO_ or VNC_ = 1.5V,
RL = 50Ω, CL = 35pF,
Figure 2
TA = +25°C
400
TA = TMIN to TMAX
750
VNO or VNC = 1.5V,
RL = 50Ω,
CL = 35pF, Figure 2
TA = +25°C
200
TA = TMIN to TMAX
750
ns
ns
RL = 50Ω, CL = 35pF, Figure 3
80
Rx interface
8
Tx interface
20
Rx interface
300
Tx interface
300
RL = 50Ω, CL = 35pF,
f < 3MHz
-65
VISO2
RL = 50Ω, CL = 35pF,
3MHz < f < 30MHz
-58
VISO1
RL = 50Ω, CL = 35pF,
f < 3MHz
-60
RL = 50Ω, CL = 35pF,
3MHz < f < 30MHz
-40
RL = 50Ω, CL = 35pF,
f < 3MHz
-65
VCT2
RL = 50Ω, CL = 35pF,
3MHz < f < 30MHz
-50
VCT1
RL = 50Ω, CL = 35pF,
f < 3MHz
-78
RL = 50Ω, CL = 35pF,
3MHz < f < 30MHz
-30
Charge Injection
Q
On-Channel
3dB Bandwidth
BW
VGEN = 1.5V, RGEN =
0Ω, CL = 1nF, Figure 4
VISO1
ns
pC
MHz
Rx interface
Off-Isolation (Note 7)
dB
Tx interface
VISO2
VCT1
Rx interface,
Figure 5
Crosstalk (Note 8)
dB
Tx interface,
Figure 5
VCT2
NC_ or NO_ Off-Capacitance
COM_ On-Capacitance
COFFRX
Rx interface f = 1MHz, Figure 6
12
COFFTX
Tx interface f = 1MHz, Figure 6
40
CCOM(ON)TX
CCOM(ON)RX
f = 1MHz
Rx interface
24
Tx interface
60
pF
pF
_______________________________________________________________________________________
3
MAX4670
ELECTRICAL CHARACTERISTICS (continued)
ELECTRICAL CHARACTERISTICS (continued)
(V+ = +2.7V to +3.6V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C, unless otherwise noted.) (Notes 2, 3)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
0.5
V
µA
DIGITAL I/O (IN_, SWITCH )
Input-Low Voltage
VIL
V+ = 2.7V
Input-High Voltage
VIH
V+ = 3.6V
1.4
Input Leakage Current
IIL
VIN_ = 0 or V+, V SWIT C H = 0 or V+
-1
+1
2.7
3.6
V
10
µA
V
SUPPLY
Operating Voltage Range
V+
Supply Current
I+
V+ = 3.6V, VIN_ = V SWIT C H = 0 or V+
The algebraic convention is used in this data sheet. The most negative value is shown in the minimum column.
Devices are 100% tested at hot and room and guaranteed by design at cold.
∆RON = RON(MAX) - RON(MIN).
Guaranteed by design.
Flatness is defined as the difference between the maximum and minimum value of on-resistance as measured over the
specified analog signal ranges.
Note 7: Off-isolation = 20log10 [VCOM_ / (VNO_ or VNC_)], VCOM_ = output, VNO_ or VNC_ = input to off switch.
Note 8: Crosstalk between any two switches.
Note 2:
Note 3:
Note 4:
Note 5:
Note 6:
Typical Operating Characteristics
(V+ = 3.0V, TA = +25°C, unless otherwise noted.)
V+ = 3V
TA = +85°C
0.8
TA = +25°C
0.6
0.4
TA = -40°C
0.6
0.2
0
0
0.6
1.2
1.8
VCOM_ (V)
4
2.4
3.0
3.6
9
8
V+ = 2.7V
7
6
5
4
V+ = 3.6V
0.5
10
ON-RESISTANCE (Ω)
V+ = 2.7V
0.7
1.0
ON-RESISTANCE (Ω)
0.8
ON-RESISTANCE
vs. COM_VOLTAGE (Rx INTERFACE)
MAX4670 toc02
1.2
MAX4670 toc01
0.9
ON-RESISTANCE vs. COM_ VOLTAGE
OVER TEMPERATURE (Tx INTERFACE)
MAX4670 toc03
ON-RESISTANCE
vs. COM_VOLTAGE (Tx INTERFACE)
ON-RESISTANCE (Ω)
MAX4670
Integrated T1/E1/J1 Short-Haul and
Long-Haul Protection Switch
V+ = 3.6V
V+ = 3V
3
0
0.3 0.6 0.9 1.2 1.5 1.8 2.1 2.4 2.7 3.0
VCOM_ (V)
0
0.6
1.2
1.8
VCOM_ (V)
_______________________________________________________________________________________
2.4
3.0
3.6
Integrated T1/E1/J1 Short-Haul and
Long-Haul Protection Switch
ON-RESISTANCE vs. COM_ VOLTAGE
OVER TEMPERATURE (Rx INTERFACE)
ON-RESISTANCE (Ω)
8
LEAKAGE CURRENT (nA)
TA = +25°C
6
4
MAX4670toc05
TA = +85°C
10
10
MAX4670 toc04
12
COM_ LEAKAGE CURRENT
vs. TEMPERATURE (Tx INTERFACE)
1
0.1
TA = -40°C
2
0
0.01
0.3 0.6 0.9 1.2 1.5 1.8 2.1 2.4 2.7 3.0
10
35
60
NC_/NO_ LEAKAGE CURRENT
vs. TEMPERATURE (Tx INTERFACE)
COM_ LEAKAGE CURRENT
vs. TEMPERATURE (Rx INTERFACE)
LEAKAGE CURRENT (nA)
MAX4670toc06
1
NC_
0.1
NO_
85
10
0.01
1
0.1
0.01
-15
35
10
60
85
-40
-15
10
35
60
85
TEMPERATURE (°C)
TEMPERATURE (°C)
NC_/NO_ LEAKAGE CURRENT
vs. TEMPERATURE (Rx INTERFACE)
TURN-ON TIME
vs. SUPPLY VOLTAGE (Tx INTERFACE)
MAX4670 toc08
10
NC_
NO_
0.1
280
TURN-ON TIME (ns)
1
MAX4670 toc09
-40
LEAKAGE CURRENT (nA)
-15
TEMPERATURE (°C)
10
LEAKAGE CURRENT (nA)
-40
VCOM_ (V)
MAX4670 toc07
0
250
220
190
160
130
100
0.01
-40
-15
10
35
TEMPERATURE (°C)
60
85
2.7 2.8 2.9 3.0 3.1 3.2 3.3 3.4 3.5 3.6
SUPPLY VOLTAGE (V)
_______________________________________________________________________________________
5
MAX4670
Typical Operating Characteristics (continued)
(V+ = 3.0V, TA = +25°C, unless otherwise noted.)
Typical Operating Characteristics (continued)
(V+ = 3.0V, TA = +25°C, unless otherwise noted.)
30
20
10
tON
85
80
75
70
tOFF
65
60
0
250
225
200
175
150
125
100
-40
-15
10
35
85
60
SUPPLY VOLTAGE (V)
SUPPLY VOLTAGE (V)
TEMPERATURE (°C)
TURN-OFF TIME
vs. TEMPERATURE (Tx INTERFACE)
TURN-ON/OFF TIMES
vs. TEMPERATURE (Rx INTERFACE)
CHARGE INJECTION
vs. COM_ VOLTAGE (Tx INTERFACE)
34
32
30
28
26
24
40
30
tOFF
20
150
10
MAX4670 toc15
50
TURN-ON/OFF TIMES (ns)
36
tON
CHARGE INJECTION (pC)
V+ = 3V
MAX4670 toc14
60
MAX4670 toc13
40
38
V+ = 3V
300
275
3.6
2.7 2.8 2.9 3.0 3.1 3.2 3.3 3.4 3.5
2.7 2.8 2.9 3.0 3.1 3.2 3.3 3.4 3.5 3.6
TURN-OFF TIME (ns)
400
375
350
325
TURN-ON TIME (ns)
40
TURN-ON TIME
vs. TEMPERATURE (Tx INTERFACE)
MAX4670 toc11
90
TURN-ON/OFF TIMES (ns)
50
TURN-OFF TIME (ns)
95
MAX4670 toc10
60
TURN-ON/OFF TIMES
vs. SUPPLY VOLTAGE (Rx INTERFACE)
MAX4670 toc12
TURN-OFF TIME
vs. SUPPLY VOLTAGE (Tx INTERFACE)
120
90
60
30
22
0
20
-15
10
35
60
-15
10
35
60
85
0
1.0
1.5
2.0
TEMPERATURE (°C)
VCOM (V)
CHARGE INJECTION
vs. COM_ VOLTAGE (Rx INTERFACE)
FREQUENCY RESPONSE
(Tx INTERFACE)
FREQUENCY RESPONSE
(Rx INTERFACE)
ON LOSS
0
20
0
ON LOSS
-20
6
-40
OFF-ISOLATION
-60
-80
4
-100
2
CROSSTALK
1.0
1.5
VCOM_ (V)
2.0
2.5
3.0
CROSSTALK
-60
-80
OFF-ISOLATION
-120
-140
0.5
-40
-100
-120
0
3.0
-20
ON LOSS (dB)
ON LOSS (dB)
8
2.5
MAX4670 toc18
20
MAX4670 toc16
10
0
0.5
TEMPERATURE (°C)
12
6
0
-40
85
MAX4670 toc17
-40
CHARGE INJECTION (pC)
MAX4670
Integrated T1/E1/J1 Short-Haul and
Long-Haul Protection Switch
0.1
1
10
100
FREQUENCY (MHz)
1000
-140
0.1
1
10
100
FREQUENCY (MHz)
_______________________________________________________________________________________
1000
Integrated T1/E1/J1 Short-Haul and
Long-Haul Protection Switch
PIN
NAME
—
N.C.
No Connection. Not internally connected.
FUNCTION
1
INB
Transmitter 1 Logic Control. Drive INB high to connect NC3 and NC4. INB logic is ignored
when SWITCH asserts low.
2
COM3
Common Terminal 3. Transmitter 1 positive differential terminal. Connect COM3 to the transmit
interface transformer.
3
COM4
Common Terminal 4. Transmitter 1 negative differential terminal. Connect COM4 to the
transmit interface transformer.
4
GND
Ground
5
INC
Transmitter 2 Logic Control. Drive INC high to connect NC5 and NC6. INC logic is ignored
when SWITCH asserts low.
6
COM5
Common Terminal 5. Transmitter 2 positive differential terminal. Connect COM5 to the transmit
interface transformer.
7
COM6
Common Terminal 6. Transmitter 2 negative differential terminal. Connect COM6 to the
transmit interface transformer.
8
SWITCH
9, 32
V+
Positive Supply Voltage. Bypass V+ to ground with a 0.1µF ceramic capacitor.
10
IND
Receiver 2 Logic Control. Drive IND high to connect NC7 and NC8. IND logic is ignored when
SWITCH asserts low.
11
COM7
Common Terminal 7. Receiver 2 positive differential terminal. Connect COM7 to the receive
interface transformer.
12
COM8
Common Terminal 8. Receiver 2 negative differential terminal. Connect COM8 to the receive
interface transformer.
13
NO8
Normally Open Terminal 8. Receiver 2 differential protection terminal. Connect NO8 to the
protection bus.
14
NC8
Normally Closed Terminal 8. Receiver 2 differential terminal. Connect NC8 to LIU receiver.
15
NO7
Normally Open Terminal 7. Receiver 2 differential protection terminal. Connect NO7 to the
protection bus.
16
NC7
Normally Closed Terminal 7. Receiver 2 differential terminal. Connect NC7 to LIU receiver.
17
NO6
Normally Open Terminal 6. Transmitter 2 differential protection terminal. Connect NO6 to the
protection bus.
18
NC6
Normally Closed Terminal 6. Transmitter 2 differential terminal. Connect NC6 to LIU receiver.
19
NO5
Normally Open Terminal 5. Transmitter 2 differential protection terminal. Connect NO5 to the
protection bus.
20
NC5
Normally Closed Terminal 5. Transmitter 2 differential terminal. Connect NC5 to LIU receiver.
21
NO4
Normally Open Terminal 4. Transmitter 1 differential protection terminal. Connect NO4 to the
protection bus.
Protection Switch Control. Assert SWITCH low to connect all switches to protection bus. When
SWITCH asserts low, SWITCH overrides all IN_ inputs. Assert SWITCH high to enable all
switches and let the respective IN control the switches.
_______________________________________________________________________________________
7
MAX4670
Pin Description
Integrated T1/E1/J1 Short-Haul and
Long-Haul Protection Switch
MAX4670
Pin Description (continued)
PIN
NAME
22
NC4
Normally Closed Terminal 4. Transmitter 1 differential terminal. Connect NC4 to LIU receiver.
FUNCTION
23
NO3
Normally Open Terminal 3. Transmitter 1 differential protection terminal. Connect NO3 to the
protection bus.
24
NC3
Normally Closed Terminal 3. Transmitter 1 differential terminal. Connect NC3 to LIU receiver.
25
NO2
Normally Open Terminal 2. Receiver 2 differential protection terminal. Connect NO2 to the
protection bus.
26
NC2
Normally Closed Terminal 2. Receiver 1 differential terminal. Connect NC2 to LIU receiver.
27
NO1
Normally Open Terminal 1. Receiver 1 differential protection terminal. Connect NO1 to the
protection bus.
28
NC1
Normally Closed Terminal 1. Receiver 1 differential terminal. Connect NC1 to LIU receiver.
29
COM1
Common Terminal 1. Receiver 1 positive differential terminal. Connect COM1 to the receive
interface transformer.
30
COM2
Common Terminal 2. Receiver 1 negative differential terminal. Connect COM2 to the receive
interface transformer.
31
INA
Receiver 1 Logic Control. Drive INA low to connect receiver 1 to the LIU. INA logic is ignored
when SWITCH asserts low.
EP
EP
Exposed Paddle. Connect EP to GND or leave unconnected.
Detailed Description
The MAX4670 is a quad-DPDT/octal-SPDT analog switch
optimized for T1/E1/J1 line-card redundancy protection
applications. This analog switch is configurable as two
differential transmitter and receiver pairs utilized in
T1/E1/J1 redundancy architecture.
The MAX4670 has four low 0.7Ω on-resistance switches
with 60pF and 40pF on- and off-capacitances, respectively, for interfacing to the LIU transmitter inputs. The
MAX4670 also includes four 5Ω on-resistance switches
with low 24pF and 12pF on- and off-capacitances,
respectively, for interfacing to the LIU receiver inputs.
The MAX4670 replaces two diode arrays or two transient voltage suppressors and four dual-SPDT relays,
significantly reducing board space and simplifying PC
board routing. The MAX4670 pinouts are targeted for
T1/E1/J1 applications, resulting in a simplified layout
when interfacing with standard line transformers and
LIUs. Figure 1 is the functional diagram.
Logic Inputs (IN_, SWITCH)
The MAX4670 four logic inputs (IN_) control the switches
in pairs and contain a global logic input (SWITCH) that
connects all COMs to their respective NO_ inputs.
SWITCH overrides all IN_ inputs when asserted low, thus
connecting all NO_ to COM_ outputs (transmitter/receiver
8
pairs to the protection bus). When SWITCH asserts high,
IN_ controls the switch pairs. See Table 1.
Surge Protection
The MAX4670 includes chip-side, surge-protection capability for short-haul intrabuilding applications. The lowcapacitance diodes suppress surge residuals from the
primary, line-side protection devices. It is assumed that
adequate primary protection is included on the line die of
the transformer, as represented in Figures 7–10. Table 2
lists the applicable surge protection setups for E1
interfaces. The MAX4670 surge test was performed per
IEC 61000-4-5 Class 2 specifications and passed at ±1kV
with only an in-line transformer and primary surge suppressor. The transformer was a Halo TG83-1505NX transformer and the surge suppressor was a Teccor P0640SC.
Applications Information
Redundancy Architecture
Figures 7 through 10 illustrate the MAX4670 used in two
different redundancy architectures. There is one backup card for up to N line cards in the system (in this
example, N = 3). In the event one of the line cards fails
(memory failure, power supply went down, etc.), a system supervisory card issues a command to the switches to reroute the traffic to and from the problem line
card to the backup line card.
_______________________________________________________________________________________
Integrated T1/E1/J1 Short-Haul and
Long-Haul Protection Switch
MAX4670
V+
SWITCH
LOW
HIGH
HIGH
MAX4670
RX
NO1
COM1
LOW
HIGH
HIGH
COM2
LOW
HIGH
HIGH
NC1
RX
NO2
INA
NC2
0.6Ω
TX
NO3
COM3
0.6Ω
NC3
0.6Ω
TX
NO4
0.6Ω
LOW
HIGH
HIGH
INA
X
LOW
HIGH
INB
X
LOW
HIGH
INC
X
LOW
HIGH
IND
X
LOW
HIGH
NC1/NC2
OFF
OFF
ON
NC3/NC4
OFF
OFF
ON
NC5/NC6
OFF
OFF
ON
NC7/NC8
OFF
OFF
ON
NO1/NO2
ON
ON
OFF
NO3/NO4
ON
ON
OFF
NO5/NO6
ON
ON
OFF
NO7/NO8
ON
ON
OFF
COM4
INB
NC4
0.6Ω
TX
NO5
COM5
0.6Ω
NC5
0.6Ω
TX
NO6
0.6Ω
COM6
INC
NC6
RX
NO7
COM7
NC7
RX
NO8
COM8
IND
NC8
GND
SWITCH
Figure 1. Functional Diagram
In a switching-card architecture, a common switching
card contains all the protection switches for the T1/E1/J1
lines entering the system (see Figures 7 and 8).
With an adjacent card architecture, the switches protecting any given line card reside physically in the adjacent line card (see Figures 9 and 10).
Receive and transmit interfaces reside in the same
board for each T1/E1/J1 port. The diagrams represent
the typical interface transformers and resistors recommended for Dallas/Maxim LIUs, such as the DS21Q55.
The protection switches are placed in the low-voltage
side of the transformer to meet the isolation requirements. Note that there is also a TVS in the line side of
the transformers. The receive and transmit resistors provide impedance matching to the T1/E1/J1 transmission
cable characteristic impedance. Refer to Application
Note 2857 for more information on T1/E1/J1 applications.
_______________________________________________________________________________________
9
MAX4670
Integrated T1/E1/J1 Short-Haul and
Long-Haul Protection Switch
Table 1. MAX4670 Truth Table
SWITCH
INA
NC1/NC2
NO1/NO2
LOW
X
OFF
ON
HIGH
LOW
OFF
ON
HIGH
HIGH
ON
OFF
—
INB
NC3/NC4
NO3/NO4
LOW
X
OFF
ON
HIGH
LOW
OFF
ON
HIGH
HIGH
ON
OFF
The receive interface series resistance is small enough
to support LIUs with internal line termination, provided
the external 120Ω parallel resistor combination (Rr) is
connected, as shown in Figures 7 and 9.
While in normal operation, the MAX4670 requires the
input and output signals to be within the V+ and GND
supply rails.
ESD Test Conditions
ESD performance depends on a variety of conditions.
Contact Maxim for a reliability report that documents
test setup, test methodology, and test results.
—
INC
NC5/NC6
NO5/NC6
LOW
X
OFF
ON
Human Body Model
HIGH
LOW
OFF
ON
HIGH
HIGH
ON
OFF
—
IND
NC7/NC8
NO7/NO8
LOW
X
OFF
ON
HIGH
LOW
OFF
ON
Figure 11 shows the Human Body Model. Figure 12
shows the current waveform it generates when discharged into a low impedance. This model consists of a
100pF capacitor charged to the ESD voltage of interest,
which is then discharged into the test device through a
1.5kΩ resistor.
HIGH
HIGH
ON
OFF
Table 2. IEC 61000-4-5 Test Conditions
TEST CONFIGURATION
TEST CONDITIONS
Differential Surge
(Line to Line)
500V peak, 12A min current,
8µs/20µs surge
Common-Mode Surge
(Line to GND)
1000V peak, 24A min current,
8µs/20µs surge
LIU Interface Recommendations
The MAX4670 low 0.7Ω (typ) on-resistance is adequate, even in applications where the LIUs require no
external series transmit resistors (Rt = 0 in Figures 8
and 10). However, in some instances, increase the LIU
output amplitude to compensate for RON if the LIU supports programmable output amplitude. With LIUs
requiring external transmit resistors, it is recommended
to reduce Rt by the amount of the typical RON with LIUs
requiring external transmit resistors.
For example, if the LIU vendor recommends Rt = 9.1Ω,
the actual value in the application should be:
IEC 1000-4-2
The IEC 1000-4-2 standard covers ESD testing and
performance of finished equipment. It does not specifically refer to ICs. The major difference between tests
done using the Human Body Model and IEC 1000-4-2
is a higher peak current in IEC 1000-4-2, because
series resistance is lower in the IEC 1000-4-2 model.
Hence, the ESD withstands voltage measured to IEC
61000-4-2, and is generally lower than that measured
using the Human Body Model. Figure 13 shows the IEC
61000-4-2 model, and Figure 14 shows the current
waveform for the ±8kV IEC, 61000-4-2 Level 4, ESD
Contact Discharge test. The Air-Gap test involves
approaching the device with a charged probe. The
Contact Discharge method connects the probe to the
device before the probe is energized.
Machine Model
The Machine Model for ESD tests all pins using a
200pF storage capacitor and zero discharge resistance. Its objective is to emulate the stress caused by
contact that occurs with handling and assembly during
manufacturing.
Rt = Rt – RON = 9.1Ω - 0.7 = 8.4Ω
10
______________________________________________________________________________________
Integrated T1/E1/J1 Short-Haul and
Long-Haul Protection Switch
V+
0.1µF
MAX4670
LOGIC
INPUT
V+
V NO_
OR
V NC_
NO_
OR NC_
50%
VINL
VOUT
COM_
RL
50Ω
CL
35pF
t OFF
IN_
VOUT
GND
LOGIC
INPUT
SWITCH
OUTPUT
(
0.9 × V0UT
0.9 × VOUT
0V
t ON
CL INCLUDES FIXTURE AND STRAY CAPACITANCE.
RL
RL + RON
VOUT = VN_
t r < 5ns
t f < 5ns
VINH
LOGIC INPUT WAVEFORMS INVERTED FOR SWITCHES
THAT HAVE THE OPPOSITE LOGIC SENSE.
)
WHERE, VN_ IS VNC_ OR VNO_.
Figure 2. Switching Time
V+
0.1µF
MAX4670
LOGIC
INPUT
V+
NC_
VNO_
OR
VNC_
50%
VINL
VOUT
COM_
VINH
NO_
RL
50Ω
IN_
LOGIC
INPUT
CL
35pF
GND
0.9 × VOUT
VOUT
tD
CL INCLUDES FIXTURE AND STRAY CAPACITANCE.
Figure 3. Break-Before-Make Intervals
V+
0.1µF
∆VOUT
MAX4670
VOUT
V+
RGEN
NC_
OR NO_
COM_
VOUT
IN_
OFF
CL
V GEN
GND
ON
OFF
IN_
IN_
VINL TO VINH
OFF
ON
OFF
Q = (∆V OUT )(C L )
IN DEPENDS ON SWITCH CONFIGURATION;
INPUT POLARITY DETERMINED BY SENSE OF SWITCH.
Figure 4. Charge Injection
______________________________________________________________________________________
11
MAX4670
Test Circuits/Timing Diagrams
MAX4670
Integrated T1/E1/J1 Short-Haul and
Long-Haul Protection Switch
Test Circuits/Timing Diagrams (continued)
+3V 0.1µF
V
OFF-ISOLATION = 20log OUT
VIN
NETWORK
ANALYZER
0 OR V+
IN_
NC_
V+
NO_
50Ω
VIN
MAX4670
COM_
50Ω
MEAS
VOUT
GND
V
ON-LOSS = 20log OUT
VIN
50Ω
REF
50Ω
V
CROSSTALK = 20log OUT
VIN
50Ω
MEASUREMENTS ARE STANDARDIZED AGAINST SHORTS AT IC TERMINALS.
OFF-ISOLATION IS MEASURED BETWEEN COM_ AND "OFF" NO_ OR NC_ TERMINAL ON EACH SWITCH.
ON-LOSS IS MEASURED BETWEEN COM_ AND "ON" NO_ OR NC_TERMINAL ON EACH SWITCH.
CROSSTALK IS MEASURED FROM ONE CHANNEL TO ALL OTHER CHANNELS.
SIGNAL DIRECTION THROUGH SWITCH IS REVERSED; WORST VALUES ARE RECORDED.
Figure 5. On-Loss, Off-Isolation, and Crosstalk
0.1µF
V+
V+
COM_
MAX4670
IN_
CAPACITANCE
METER
f = 1MHz
NC_ OR
NO_
VINL
OR
VINH
GND
Figure 6. Channel Off-/On-Capacitance
12
______________________________________________________________________________________
Integrated T1/E1/J1 Short-Haul and
Long-Haul Protection Switch
MAX4670
RECEIVE PATH
PROTECTION SWITCHING CARD
PROTECTION BUS
LINE CARD 1
RTIP
NO1
LIU RX
1:1
COM1
NC1
Rr
U1
Rr
RRING
COM2
NC2
NO2
LINE CARD 2
RTIP
COM7
NC7
NO7
1:1
Rr
LIU RX
U1
Rr
RRING
COM8
NC8
NO8
LINE CARD 3
RTIP
COM7
NC7
NO7
1:1
Rr
LIU RX
U2
Rr
RRING
NC8
COM8
NO8
BACKUP LINE CARD
RTIP
LIU RX
RRING
Figure 7. Switching-Card-Architecture Receive Path
______________________________________________________________________________________
13
MAX4670
Integrated T1/E1/J1 Short-Haul and
Long-Haul Protection Switch
TRANSMIT PATH
PROTECTION SWITCHING CARD
COM3
NO3
LINE CARD 1
RT
TRING
PROTECTION BUS
1:1
NC3
U1
LIU TX
COM4
NO4
RT
TTIP
NC4
COM5
NO5
LINE CARD 2
RT
TRING
1:1
NC5
U1
LIU TX
COM6
NO6
RT
TTIP
NC6
COM5
NO5
LINE CARD 3
RT
TRING
1:1
NC5
U2
LIU TX
NO6
RT
TTIP
COM6
NC6
BACKUP LINE CARD
TTIP
LIU TX
TRING
Figure 8. Switching-Card-Architecture Transmit Path
14
______________________________________________________________________________________
Integrated T1/E1/J1 Short-Haul and
Long-Haul Protection Switch
MAX4670
RECEIVE PATH
PROTECTION
BUS
LINE CARD 1
MAX4670
COM1
NO1
COM2
NO2
1:1
RTIP
Rr
LIU RX
Rr
RRING
LINE CARD 2
MAX4670
COM1
NO1
COM2
NO2
1:1
RTIP
Rr
LIU RX
Rr
RRING
LINE CARD 3
MAX4670
COM1
NO1
COM2
NO2
1:1
RTIP
Rr
LIU RX
Rr
RRING
BACKUP LINE CARD
RTIP
LIU RX
RRING
Figure 9. Adjacent-Card-Architecture Receive Path
______________________________________________________________________________________
15
MAX4670
Integrated T1/E1/J1 Short-Haul and
Long-Haul Protection Switch
TRANSMIT PATH
PROTECTION
BUS
LINE CARD 1
MAX4670
COM3
NO3
COM4
NO4
RT
1:2
TTIP
LIU Tx
RT
TRING
LINE CARD 2
MAX4670
COM3
NO3
COM4
NO4
RT
1:2
TTIP
LIU Tx
RT
TRING
LINE CARD 3
MAX4670
RT
TTIP
COM3
NO3
COM4
NO4
1:2
LIU Tx
RT
TRING
BACKUP LINE CARD
RT
RTIP
LIU Tx
RT
RRING
Figure 10. Adjacent-Card-Architecture Transmit Path
16
______________________________________________________________________________________
Integrated T1/E1/J1 Short-Haul and
Long-Haul Protection Switch
CHARGE-CURRENTLIMIT RESISTOR
HIGHVOLTAGE
DC
SOURCE
Cs
100pF
RC
50MΩ TO 100MΩ
RD
1500Ω
CHARGE-CURRENTLIMIT RESISTOR
DISCHARGE
RESISTANCE
DEVICE
UNDER
TEST
STORAGE
CAPACITOR
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
DEVICE
UNDER
TEST
I
100%
90%
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
I PEAK
Ir
Cs
150pF
RD
330Ω
Figure 13. IEC 1000-4-2 ESD Test Model
Figure 11. Human Body ESD Test Model
IP 100%
90%
HIGHVOLTAGE
DC
SOURCE
MAX4670
RC
1MΩ
AMPERES
36.8%
10%
0
10%
0
tRL
TIME
tDL
CURRENT WAVEFORM
Figure 12. Human Body Model Current Waveform
t r = 0.7ns TO 1ns
t
30ns
60ns
Figure 14. IED 1000-4-2 ESD Generator Current Waveform
______________________________________________________________________________________
17
Integrated T1/E1/J1 Short-Haul and
Long-Haul Protection Switch
MAX4670
Functional Diagram/Truth Table
V+
SWITCH
LOW
HIGH
HIGH
MAX4670
RX
NO1
COM1
LOW
HIGH
HIGH
COM2
LOW
HIGH
HIGH
NC1
RX
NO2
INA
NC2
0.6Ω
TX
NO3
COM3
0.6Ω
NC3
0.6Ω
TX
NO4
0.6Ω
LOW
HIGH
HIGH
INA
X
LOW
HIGH
INB
X
LOW
HIGH
INC
X
LOW
HIGH
IND
X
LOW
HIGH
NC1/NC2
OFF
OFF
ON
NC3/NC4
OFF
OFF
ON
NC5/NC6
OFF
OFF
ON
NC7/NC8
OFF
OFF
ON
NO1/NO2
ON
ON
OFF
NO3/NO4
ON
ON
OFF
NO5/NO6
ON
ON
OFF
NO7/NO8
ON
ON
OFF
COM4
INB
NC4
0.6Ω
TX
NO5
COM5
0.6Ω
NC5
0.6Ω
TX
NO6
0.6Ω
COM6
INC
NC6
RX
NO7
COM7
NC7
RX
NO8
COM8
IND
NC8
GND
SWITCH
Chip Information
PROCESS: CMOS
18
______________________________________________________________________________________
Integrated T1/E1/J1 Short-Haul and
Long-Haul Protection Switch
QFN THIN.EPS
______________________________________________________________________________________
19
MAX4670
Package Information (continued)
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)
MAX4670
Integrated T1/E1/J1 Short-Haul and
Long-Haul Protection Switch
Package Information (continued)
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
20 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2005
2006 Maxim Integrated Products
is a registered trademark of Maxim Integrated Products, Inc.
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