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HMC856 single ended control lines

Category: Hardware
Product Number: HNC856
Software Version: N/A

I need to drive the device with single-ended control lines. The data sheet says that the min voltage is -1.5 and max is +0.5V. I'm looking for confirmation of my understanding as the datasheet "typical application circuit" has some inconsistencies that might be revealing a misunderstanding on my part.

The datasheet shows a "typical application circuit"  with series 2.7K resistors to the positive inputs for all BUT the B0+ input. There is a 1.2K resistor (R2) to "VS" which also goes to all the negative inputs and  looks like it wants to be signal ground.  I suspect R2 is an error. It does appear in the eval board Gerber artwork, connected to VS as are pin 7, 10, 13, 16, and 18, but the other end seems a ground (Metal four is a power ground  (?) )  if C1, C2, C4, and C5 are an indication. It's not clear to me what role R2 plays.  In any event this is different from the schematic that connects R2 between  VS and B0+

I think all of the Bx- are intended to be simply at ground potential.  And I further think the drive to the 2.7K resistors should either float or get pulled to Vee (-3.3V)  I'm somewhat inclined to add a pullup to ground at the drive point to insure they 'float' to ground reliably.

Can anyone confirm/check this?