DS21458-W+ Maxim Integrated, DS21458-W+ Datasheet - Page 222

• Manufacturer Part Number: DS21458-W+
• Description: Network Controller & Processor ICs
• Manufacturer: Maxim Integrated

Specifications of DS21458-W+

• Product: Framer
• Number Of Transceivers: 4
• Data Rate: 64 Kbps
• Supply Current (max): 328 mA
• Maximum Operating Temperature: + 70 C
• Mounting Style: SMD/SMT
• Package / Case: CSBGA
• Minimum Operating Temperature: 0 C
• Operating Supply Voltage: 3.3 V
• Supply Voltage - Max: 3.465 V
• Supply Voltage - Min: 3.135 V
• Part # Aliases: 90-21458+W00

DS21455/DS21458 Quad T1/E1/J1 Transceivers
35.2 Test Registers
IEEE 1149.1 requires a minimum of two test registers: the bypass register and the boundary scan register.
An optional test register has been included with the DS21455/DS21458 design. This test register is the
identification register and is used with the IDCODE instruction and the test-logic-reset state of the TAP
controller.
35.3 Boundary Scan Register
This register contains both a shift register path and a latched parallel output for all control cells and
digital I/O cells and is n bits in length. See
Table 35-4
for the cell bit locations and definitions.
35.4 Bypass Register
This is a single 1-bit shift register used with the BYPASS, CLAMP, and HIGH-Z instructions that
provides a short path between JTDI and JTDO.
35.5 Identification Register
The identification register contains a 32-bit shift register and a 32-bit latched parallel output. This register
is selected during the IDCODE instruction and when the TAP controller is in the test-logic-reset state.
See
Table 35-2
and
Table 35-3
for more information about bit usage.
222 of 269