DS26900 Datasheet, PDF (1/50 Pages) Maxim Integrated Products – JTAG Multiplexer/Switch

Rev: 072707
DS26900
JTAG Multiplexer/Switch
General Description
The DS26900 is a JTAG signal multiplexer providing
connectivity between one of three master ports and
up to 18 (36 in cascade configuration) secondary
ports. The device is fully configurable from any one of
the three master ports. The DS26900 can
automatically detect the presence JTAG devices on
the secondary ports.
The DS26900 can be used in multiple configurations
including as a single device, two cascaded devices,
or two redundant devices.
All device control and configuration is accomplished
through standard JTAG operations via the selected
master port.
MicroTCA Chassis
ATCA Chassis
AMC Carrier Cards
JSM Modules
System Level JTAG
Applications
MicroTCA JSM Functional Diagram
MCH1
MASTER3
MCH2
MASTER2
CRAFT
MASTER1
DS26900
JTAG
SWITCH
AMC1
AMC2
AMC3
AMC4
AMCn
AMC18
Features
♦ Efficient Solution for Star Architecture JTAG
♦ Provides Transparent Communications
Between the Arbitrated Master and a Selected
Secondary Port
♦ Single-Package Solution Provides 18
Secondary Ports
♦ Two-Package Cascade Configuration
Provides 36 Secondary Ports
♦ Three Arbitrated Master Ports
♦ Autodetection of Port Presence
♦ Internal Pullup/Down Resistors
♦ Two 32-Bit Scratchpad Registers
♦ Four GPIO Pins for Read/Write Control and
Signaling Applications
♦ Operation Up to 50MHz
♦ Signal Path Modification Options
♦ Redundancy with High-Impedance Pin
♦ Independent Periphery JTAG
♦ Configuration Mode Uses IEEE 1149.1 TAP
Controller
♦ Supports Live Insertion/Withdrawal
♦ 3.3V Operation
♦ Industrial Temperature Operation
♦ RoHS-Compliant Packaging
Ordering Information
PART
DS26900N+
TEMP RANGE
-40°C to +85°C
+Denotes a lead-free package.
PIN-PACKAGE
144 LQFP
_____________________________________________ Maxim Integrated Products 1
Some revisions of this device may incorporate deviations from published specifications known
as errata. Multiple revisions of any device may be simultaneously available through various sales
channels. For information about device errata, go to: www.maxim-ic.com/errata. For pricing,
delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit
Maxim’s website at www.maxim-ic.com.