MAX4670:Integrated T1/E1/J1 Short-Haul and Long-Haul Protection Switches

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 active-low 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.

Key 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
MAX4670: Functional Diagram
MAX4670: Functional Diagram
DataSheet
titleDownload file
MAX4670 Data SheetMAX4670.pdf
Parametrics
Part NumberConfig.ChannelsNormal PositionVSUPPLY (Single)
(V)
VSUPPLY (Single)
(V)
VSIGNAL
(V)
VSIGNAL
(V)
Dynamic Range (max)
(V)
RON
(Ω)
RFLAT(ON)
(Ω)
RFLAT(ON)
(Ω)
Bandwidth
(MHz)
IL(OFF)
(nA)
tON
(ns)
tOFF
(ns)
QINJECTION
(pC)
CON
(pF)
COFF
(pF)
Package/PinsBudgetary
Price
minmaxminmaxmaxmaxtypmaxmaxminmaxSee Notes
MAX46702-to-1
DPDT
8Open/Closed2.73.603.63.6920.18300.0140020082412TQFN/32$4.79 @1k
Ordering Information
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX4670ETJNo Longer AvailableMAX4670ETJ+TQFN,;32 pin;26 mm²-40°C to +85°CNo
MAX4670ETJ+ActiveTQFN,;32 pin;26 mm²-40°C to +85°CLead Free
MAX4670ETJ+TActiveTQFN,;32 pin;26 mm²-40°C to +85°CLead Free
MAX4670ETJ-TNo Longer AvailableMAX4670ETJ+TQFN;32 pin-40°C to +85°CSee data sheet
MAX4670.pdf MAX4670
MAX4670.pdf MAX4670