DS21FF44 Maxim Integrated Products, DS21FF44 Datasheet - Page 89

• Manufacturer Part Number: DS21FF44
• Description: IC FRAMER E1 4X4 16CH 300-BGA
• Manufacturer: Maxim Integrated Products

Specifications of DS21FF44

• Controller Type: E1 Framer
• Interface: Parallel/Serial
• Voltage - Supply: 2.97 V ~ 3.63 V
• Current - Supply: 300mA
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 300-BGA
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

DS21FT44/DS21FF44
21.4. 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 DS21Q44 design. This test register is the
identification register and is used in conjunction with the IDCODE instruction and the Test-Logic-Reset
state of the TAP controller.
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 126 bits in length. able 21-3 shows all of the cell bit locations and definitions.
Bypass Register
This is a single 1-bit shift register used in conjunction with the BYPASS, CLAMP, and HIGH-Z
instructions, which provides a short path between JTDI and JTDO.
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.
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