SNLS544B September   2016  – October 2019 DS280BR820

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Simplified Schematic
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Electrical Characteristics – Serial Management Bus Interface
    7. 6.7 Timing Requirements – Serial Management Bus Interface
    8. 6.8 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Device Data Path Operation
      2. 7.3.2 AC-Coupled Receiver Inputs
      3. 7.3.3 Signal Detect
      4. 7.3.4 2-Stage CTLE
      5. 7.3.5 Driver DC Gain Control
      6. 7.3.6 FIR Filter (Limiting Mode)
      7. 7.3.7 Configurable SMBus Address
    4. 7.4 Device Functional Modes
      1. 7.4.1 SMBus Slave Mode Configuration
      2. 7.4.2 SMBus Master Mode Configuration (EEPROM Self Load)
    5. 7.5 Programming
      1. 7.5.1 Transfer of Data with the SMBus Interface
    6. 7.6 Register Maps
      1. 7.6.1 Register Types: Global, Shared, and Channel
      2. 7.6.2 Global Registers: Channel Selection and ID Information
        1. Table 2. Global Register Map
      3. 7.6.3 Shared Registers
        1. Table 3. Shared Register Map
      4. 7.6.4 Channel Registers
        1. Table 4. Channel Register Map
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Backplane and Mid-Plane Reach Extension
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
      2. 8.2.2 Front-Port Applications
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
      3. 8.2.3 Application Curves
        1. 8.2.3.1 Pattern Generator Characteristics
        2. 8.2.3.2 Equalizing Moderate Pre-Channel Loss
        3. 8.2.3.3 Equalizing High Pre-Channel Loss
        4. 8.2.3.4 Equalizing High Pre-Channel Loss and Moderate Post-Channel Loss
        5. 8.2.3.5 Output in FIR Limiting Mode with 16T Pattern
    3. 8.3 Initialization Set Up
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Examples
      1. 10.2.1 Stripline Example
      2. 10.2.2 Microstrip Example
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

5 Pin Configuration and Functions

Top View
DS280BR820 PinOut.gif

Pin Functions

PIN I/O DESCRIPTION
NAME NO.
HIGH SPEED DIFFERENTIAL I/O
RX0N B15 Input Inverting and non-inverting differential inputs to the equalizer. An on-chip 100-Ω termination resistor connects RXP to RXN. These inputs are AC coupled with 220-nF capacitors assembled on the package substrate.
RX0P C15 Input
RX1N A13 Input Inverting and non-inverting differential inputs to the equalizer. An on-chip 100-Ω termination resistor connects RXP to RXN. These inputs are AC coupled with 220-nF capacitors assembled on the package substrate.
RX1P B13 Input
RX2N A11 Input Inverting and non-inverting differential inputs to the equalizer. An on-chip 100-Ω termination resistor connects RXP to RXN. These inputs are AC coupled with 220-nF capacitors assembled on the package substrate.
RX2P B11 Input
RX3N A9 Input Inverting and non-inverting differential inputs to the equalizer. An on-chip 100-Ω termination resistor connects RXP to RXN. These inputs are AC coupled with 220-nF capacitors assembled on the package substrate.
RX3P B9 Input
RX4N A7 Input Inverting and non-inverting differential inputs to the equalizer. An on-chip 100-Ω termination resistor connects RXP to RXN. These inputs are AC coupled with 220-nF capacitors assembled on the package substrate.
RX4P B7 Input
RX5N A5 Input Inverting and non-inverting differential inputs to the equalizer. An on-chip 100-Ω termination resistor connects RXP to RXN. These inputs are AC coupled with 220-nF capacitors assembled on the package substrate.
RX5P B5 Input
RX6N A3 Input Inverting and non-inverting differential inputs to the equalizer. An on-chip 100-Ω termination resistor connects RXP to RXN. These inputs are AC coupled with 220-nF capacitors assembled on the package substrate.
RX6P B3 Input
RX7N B1 Input Inverting and non-inverting differential inputs to the equalizer. An on-chip 100-Ω termination resistor connects RXP to RXN. These inputs are AC coupled with 220-nF capacitors assembled on the package substrate.
RX7P C1 Input
TX0N H15 Output Inverting and non-inverting 50-Ω driver outputs. Compatible with AC-coupled differential inputs.
TX0P G15 Output
TX1N J13 Output Inverting and non-inverting 50-Ω driver outputs. Compatible with AC-coupled differential inputs.
TX1P H13 Output
TX2N J11 Output Inverting and non-inverting 50-Ω driver outputs. Compatible with AC-coupled differential inputs.
TX2P H11 Output
TX3N J9 Output Inverting and non-inverting 50-Ω driver outputs. Compatible with AC-coupled differential inputs.
TX3P H9 Output
TX4N J7 Output Inverting and non-inverting 50-Ω driver outputs. Compatible with AC-coupled differential inputs.
TX4P H7 Output
TX5N J5 Output Inverting and non-inverting 50-Ω driver outputs. Compatible with AC-coupled differential inputs.
TX5P H5 Output
TX6N J3 Output Inverting and non-inverting 50-Ω driver outputs. Compatible with AC-coupled differential inputs.
TX6P H3 Output
TX7N H1 Output Inverting and non-inverting 50-Ω driver outputs. Compatible with AC-coupled differential inputs.
TX7P G1 Output
CALIBRATION CLOCK PINS (FOR SUPPORTING UPGRADE PATH TO PIN-COMPATIBLE RETIMER DEVICE)
CAL_CLK_IN E1 Input 25-MHz (±100 PPM) 2.5-V single-ended clock from external oscillator. No stringent phase noise or jitter requirements on this clock. A 25-MHz input clock is only required if there is a need to support a future upgrade to the pin-compatible Retimer device. If there is no need to support a future upgrade to a pin-compatible Retimer device, then a 25-MHz clock is not required. This input pin has a weak active pull-down and can be left floating if the CAL_CLK feature is not required.
CAL_CLK_
OUT		 E15 Output 2.5-V buffered replica of calibration clock input (pin E1) for connecting multiple devices in a daisy-chained fashion.
SYSTEM MANAGEMENT BUS (SMBus) PINS
ADDR0 D13 Input, 4-Level 4-level strap pins used to set the SMBus address of the device. The pin state is read on power-up. The multi-level nature of these pins allows for 16 unique device addresses. The four strap options include:
0: 1 kΩ to GND
R: 10 kΩ to GND
F: Float
1: 1 kΩ to VDD
ADDR1 E13 Input, 4-Level
ALL_DONE_N D3 Output, LVCMOS Indicates the completion of a valid EEPROM register load operation when in SMBus master mode (EN_SMB = Float):
High = External EEPROM load failed or incomplete.
Low = External EEPROM load successful and complete.
When in SMBus slave mode (EN_SMB = 1 kΩ to VDD), this output will be high-Z until READ_EN_N is driven low, at which point ALL_DONE_N will be driven low. This behavior allows the reset signal connected to READ_EN_N of one device to propagate to the subsequent devices when ALL_DONE_N is connected to READ_EN_N in an SMBus slave mode application.
EN_SMB E3 Input, 4-Level 4-level 2.5-V input used to select between SMBus master mode (float) and SMBus slave mode (high). The four defined levels are:
0: 1 kΩ to GND - RESERVED
R: 10 kΩ to GND - RESERVED
F: Float - SMBus master mode
1: 1 kΩ to VDD - SMBus slave mode
READ_EN_N F13 Input, LVCMOS Pin has weak pull-up.
This pin is 3.3 V tolerant.

SMBus master mode (EN_SMB = Float): When asserted low, initiates the SMBus master mode EEPROM read function. Once EEPROM read is complete (indicated by assertion of ALL_DONE_N low), this pin can be held low for normal device operation.

SMBus slave mode (EN_SMB = 1 kΩ to VDD): When asserted low, this causes the device to be held in reset (SMBus state machine reset and register reset). This pin should be pulled high or left floating for normal operation in SMBus slave mode.

SDA E12 I/O, 3.3-V LVCMOS, Open Drain SMBus data input and open drain output. External 2-kΩ to 5-kΩ pull-up resistor is required. This pin is 3.3-V LVCMOS tolerant.
SDC F12 I/O, 3.3-V LVCMOS, Open Drain SMBus clock input and open drain clock output. External 2-kΩ to 5-kΩ pull-up resistor is required. This pin is 3.3-V LVCMOS tolerant.
MISCELLANEOUS PINS
INT_N F3 No Connect No connect on package. For applications using multiple repeaters and retimers, this pin should be connected to other devices’ INT_N pins. This is only a recommendation for cases where there is a need to support a potential future upgrade to the pin-compatible retimer device, which uses this pin as an interrupt signal to a system controller.
TEST0 E2 Input, LVCMOS Reserved test pin. During normal (non-test-mode) operation, this pin is configured as an input and therefore is not affected by the presence of a signal. This pin may be left floating, tied to GND, or connected to a 2.5-V (max) output.
TEST1 E14 Input, LVCMOS
POWER
GND A1, A2, A4, A6, A8, A10, A12, A14, A15, B2, B4, B6, B8, B10, B12, B14, C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, D1, D2, D4, D5, D7, D9, D11, D12, D14, D15, E4, E11, F1, F2, F4, F5, F7, F9, F11, F14, F15, G2, G3, G4, G5, G6, G7, G8, G9, G10, G11, G12, G13, G14, H2, H4, H6, H8, H10, H12, H14, J1, J2, J4, J6, J8, J10, J12, J14, J15 Power Ground reference. The GND pins on this device should be connected through a low-impedance path to the board GND plane.
VDD D6, D8, D10, E5, E6, E7, E8, E9, E10, F6, F8, F10 Power Power supply, VDD = 2.5 V ±5%. Use at least six de-coupling capacitors between the Repeater’s VDD plane and GND as close to the Repeater as possible. For example, four 0.1-μF capacitors and two 1-μF capacitors directly beneath the device or as close to the VDD pins as possible. The VDD pins on this device should be connected through a low-resistance path to the board VDD plane. For more information, see Power Supply Recommendations.