Ultrasound VGA Integrated

with CW Octal Mixer

4

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AC ELECTRICAL CHARACTERISTICS—VGA MODE

puts pulled up to +11V through four separate ±0.1% 115Ω resistors, differential mixer inputs are driven from a low-impedance source.

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

Mode Select Response Time

CW_VG set from logic 1 to 0 or from 0 to 1

(Note 9)

2µs

VGA MODE

Differential output

capacitance is 10pF,

capacitance to GND at

each single-ended output

Ω

17

Large-Signal Bandwidth

f-3dB

3dB bandwidth,

gain = 20dB

No capacitive load,

Ω

22

MHz

Differential Input Resistance

170

200

230

Ω

Input Effective Capacitance

15

pF

Differential Output Resistance

100

Ω

Maximum Gain

39.5

dB

Minimum Gain

-10.5

dB

Gain Range

50

dB

°C, -2.0V < VG_CTL < -1.8V,

±0.6

°C, -1.8V < VG_CTL < +1.2V,

±0.5

Absolute Gain Error

°C, +1.2V < VG_CTL < +2.0V,

±1.2

dB

VGA Gain Response Time

50dB gain change to within 1dB final value

1

µs

Input-Referred Noise

VG_CTL set for maximum gain, no input signal

2

nV/√Hz

No input signal

60

Output-Referred Noise

VG_CTL set for

+20dB of gain

1kHz offset

120

nV/√Hz

VG_CLAMP_MODE = 1,

VG_CTL set for +20dB of gain,

-55

-62

Second Harmonic

HD2

VG_CLAMP_MODE = 1,

VG_CTL set for +20dB of gain,

-62

dBc

Third-Order Intermodulation

Distortion

IMD3

VG_CTL set for +20dB of gain,

-40

-52

dBc

Channel-to-Channel Crosstalk

VG_CTL set for +20dB of gain

-80

dB