MM-PDS-0038 Rev A
Subject to Change Without Notice
IC Assembly:
The device is designed to operate with either single-ended or differential inputs. Figures 1, 2 & 3 show
the IC assembly diagrams for positive and negative supply voltages. In either case the supply should
be capacitively bypassed to the ground to provide a good AC ground over the frequency range
of interest. The backside of the chip should be connected to a good thermal heat sink.
All RF I/O’s are connected to VCC through on-chip termination resistors. This implies that when VCC
is not DC grounded (as in the case of positive supply), the RF I/O’s should be AC coupled through
series capacitors unless the connecting circuit can generate the correct levels through level shifting.
ESD Sensitivity:
Although SiGe IC’s have robust ESD sensitivities, preventive ESD measures should be taken while
storing, handling, and assembling.
Inputs are more ESD susceptible as they could expose the base of a BJT or the gate of a MOSFET.
For this reason, all the inputs are protected with ESD diodes. These inputs have been tested
to withstand voltage spikes up to 400V.
CML Logic Levels for DC Coupling (T=25˚C):
Assuming 50 Ω Terminations at Inputs and Outputs
Differential versus Single-Ended:
The MX1DS10P is fully differential to maximize signal-to-noise ratios for high-speed operation.
All high speed inputs and outputs are terminated to Vcc with on-chip resistors (refer to functional
block diagram for specific resistor values). The maximum DC voltage on any terminal must be limited
to V max to prevent damaging the termination resistors with excessive current. Regardless of bias
conditions, the following equation should be satisfied when driving the inputs differentially:
I Vdm/2 + Vcm I < Vcc ≥ Vmax
where Vdm is the differential input signal and Vcm is the common-mode voltage.
In addition to the maximum input signal levels, single-ended operation imposes additional restrictions:
the average DC value of the waveform at IC should be equal to Vcc for single-ended operation.
In practice, this is easily achieved with a single capacitor on the input acting as a DC block. The value
of the capacitor should be large enough to pass the lowest frequencies of interest. Use the positive
terminals for single-ended operation while terminating the negative terminal to Vcc.