1 Features

1• Dual-Channel, Individual SPI™-Controlled DVGA

• Single 5-V Supply

• –3-dB Bandwidth: 1.1 GHz (Max Gain)

• Flat Bandwidth Response: 300 MHz

• Channel-to-Channel Gain Matching: ±0.05 dB

• Channel-to-Channel Phase Matching: ±0.1°

• Gain:

– 30 dB to –9 dB

– 1-dB Steps ±0.2 dB

• Output Third-Order Intercept Point (OIP3):

– 43 dBm at 300 MHz

– 51 dBm at 200 MHz

• Noise Figure (NF):

– 6.5 dB (Max Gain) at 300 MHz, ZIN = 150 Ω

• Adjustable Power Consumption:

– 90 mA to 108 mA per Channel

• Power-Saving, Power-Down Feature:

– IQ < 4.5 mA per Channel

– Power-Down Pin and SPI Programmability

• Input Return Loss at 300 MHz:

– 17 dB (RS = 150 Ω)

2 Applications

• DOCSIS 3.1 CMTS Upstream Direct Sampling

Receivers

• CATV Modem Signal Scaling

• Programmable Gain IF Amplifiers

• Generic RF, IF Gain Stages

• ADC Drivers

3 Description

The LMH2832 is a high-linearity, dual-channel, digital

variable-gain amplifier (DVGA) for high-speed signal

chain and data-acquisition systems. The LMH2832 is

optimized to provide high bandwidth, low distortion,

and low noise, thus making the device ideally suited

as a dual, 14-bit, analog-to-digital converter (ADC)

driver. The device consists of one fixed-gain block

and one variable attenuator consisting of a total gain

of 30 dB with a maximum attenuation of 39 dB. The

gain range is from 30 dB to –9 dB in 1-dB gain steps

with a gain accuracy of ±0.2 dB. The input impedance

can be easily matched to 50-Ω or 75-Ω systems using

a 1:3-Ω or 1:2-Ω ratio balun, respectively. The

LMH2832 is designed to drive general-purpose ADCs

and also meets the requirements for both data over

cable service interface specification (DOCSIS) 3.0 32

quadrature amplitude modulation (QAM) carriers and

DOCSIS 3.1 wideband orthogonal frequency-division

multiplexing (OFDM) systems. With excellent NF

(6.5 dB) and linearity, the LMH2832 is designed to

perform to within DOCSIS specifications. The

quiescent current in the power-down state is less

than 5 mA per channel with the typical current

consumption during operation at 105 mA per channel.