Packaging information
| Package | Pins WQFN (RGH) | 16 |
| Operating temperature range (°C) -40 to 85 |
| Package qty | Carrier 250 | SMALL T&R |
Features for the LMH6518
- Gain Range: 40 dB
- Gain Step Size: 2 dB
- Combined Gain Resolution With Gsps ADCs:
8.5 mdB - Minimum Gain: −1.16 dB
- Maximum Gain: 38.8 dB
- −3 dB BW: 900 MHz
- Rise and Fall Time: <500 ps
- Recovery Time: <5 ns
- Propagation Delay Variation: 100 ps
- HD2 at 100 MHz: −50 dBc
- HD3 at 100 MHz: −53 dBc
- Input-Referred Noise (Maximum Gain): 0.98 nV/√Hz
- Overvoltage Clamps for Fast Recovery
- Power Consumption: Auxiliary Turned Off 1.1 W to 0.75 W
Description for the LMH6518
The LMH6518 device is a digitally controlled variable gain amplifier whose total gain is varied from −1.16 dB to 38.8 dB for a 40 dB range in 2-dB steps. The −3-dB bandwidth is 900 MHz at all gains. Gain accuracy at each setting is typically 0.1 dB. When used in conjunction with TI's Gsample/second (Gsps) ADC with adjustable full-scale (FS) range, the LMH6518 gain adjustment accommodates full scale input signals from 6.8 mVPP to 920 mVPP to get 700 mVPP nominal at the ADC input. The auxiliary output (+OUT AUX and −OUT AUX) follows the main output and is intended for use in oscilloscope trigger function circuitry but may have other uses in other applications.
The LMH6518 gain is programmed through a SPI-1 compatible serial bus. A signal path combined gain resolution of 8.5 mdB is achieved when the device's gain and the Gsps ADC’s FS input are both manipulated. Inputs and outputs are DC-coupled. The outputs are differential with individual common mode (CM) voltage control (for main and auxiliary outputs), and have a selectable bandwidth limiting circuitry (common to both main and auxiliary) of 20, 100, 200, 350, 650, 750 MHz or full bandwidth.