SNOSC72F June   2012  – February 2015 LMH6881

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and 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 Typical Characteristics
      1. 6.6.1 Single-Ended Input
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
    4. 7.4 Device Functional Modes
    5. 7.5 Programming
      1. 7.5.1 Digital Control of the Gain and Power-Down Pins
        1. 7.5.1.1 Parallel Interface
        2. 7.5.1.2 SPI-Compatible Serial Interface
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Input Characteristics
      2. 8.1.2 Output Characteristics
      3. 8.1.3 Interfacing to an ADC
        1. 8.1.3.1 ADC Noise Filter
        2. 8.1.3.2 AC Coupling to ADC
        3. 8.1.3.3 DC Coupling to ADC
      4. 8.1.4 Figure of Merit: Dynamic Range Figure
    2. 8.2 Typical Applications
      1. 8.2.1 LMH6881 Typical Application
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curves
      2. 8.2.2 LMH6881 Used as Twisted-Pair Cable Driver
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
        3. 8.2.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
      1. 10.1.1 Uncontrolled Impedance Traces
    2. 10.2 Layout Example
    3. 10.3 Thermal Considerations
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Trademarks
    3. 11.3 Electrostatic Discharge Caution
    4. 11.4 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

5 Pin Configuration and Functions

RTW Package
24-Pins WQFN
Top View
30195803.gif

Pin Functions

PIN TYPE DESCRIPTION
NO. NAME
1 NC —
2 OCM I Output Common Mode, gain of 2
3 D1, SDI I Parallel mode = Logic control signal, position 1 or weight 21
SPI mode = serial data in (SDI)
4 D0, SDO I/O Parallel mode = Logic control signal, position 0 or weight 20
SPI mode = serial data out (SDO)
5 SPI I Serial mode control
6 GND I/O Ground
7 GND I/O Ground
8 INMS I Amplifier single-ended input minus swing (negative)
9 INMD I Amplifier differential input minus swing (negative)
10 INPD I Amplifier differential input plus swing (positive)
11 INPS I Amplifier single-ended input plus swing (positive)
12 GND I/O Ground
13 GND I/O Ground
14 NC —
15 D2 I Parallel mode = Logic control signal, position 2 or weight 22 SPI mode = serial clock (CLK)
16 D3 I Parallel mode = Logic control signal, position 3 or weight 23 SPI mode = chip select (CS)
17 SD I Device Shutdown
18 NC —
19 VCC I/O Power supply nominal value of 5 V
20 VCC I/O Power supply nominal value of 5 V
21 OUTM O Amplifier output minus (negative)
22 OUTP O Amplifier output plus (positive)
23 VCC I/O Power supply nominal value of 5 V
24 VCC I/O Power supply nominal value of 5 V

Pin Descriptions

NO. SYMBOL PIN CATEGORY DESCRIPTION
ANALOG I/O
9,10 INPD, INMD Analog Input Differential inputs 100 Ω
8, 11 INPS, INMS Analog Input Single-ended inputs 50 Ω
21, 22 OUTP, OUTM Analog Output Differential outputs, low impedance
POWER
6, 7, 12, 13 GND Ground Ground pins. Connect to low impedance ground plane. All pin voltages are specified with respect to the voltage on these pins. The exposed thermal pad is internally bonded to the ground pins.
19, 20, 23, 24 VCC Power Power supply pins. Valid power supply range is 4.75 V to 5.25 V.
Exposed Center Pad Thermal/ Ground Thermal management/ Ground
DIGITAL INPUTS
5 SPI Digital Input 0 = Parallel Mode, 1 = Serial Mode
PARALLEL MODE DIGITAL PINS, SPI = LOGIC LOW
3, 4, 15, 16 D0, D1, D2, D3 Digital Input Attenuator control
17 SD Digital Input Shutdown 0 = amp on, 1 = amp off
SERIAL MODE DIGITAL PINS, SPI= LOGIC HIGH, SPI COMPATIBLE
4 SDO Digital Output - Open Emitter Serial Data Output (Requires external bias.)
3 SDI Digital Input Serial Data In
16 CS Digital Input Chip Select (active low)
15 CLK Digital Input Clock