LTC2622 SDI pin float

Question

Hello, 
 I am driving with SPI from an FPGA the LTC2622CMS8#PBF. 
 The nCS has a pull up to keep a defined state. 
 I am wondering, do I need a pull down on the SDI line? according to the datasheet table1 page 10 when nCS is high the SDI pulses define specific commands. Since the SDI will be floating on startup then the state is undefined. Is this correct or does the LTC2622CMS8#PBF have an internal pull down on the SDI pin? 
 
 Thank you

ADIApproved · Accepted Answer

Data can only be transferred to the DAC when CS is low. When it is high then the SCK and SDI are ignored. Data is latched into the register on the rising edge of chip select. There are not internal pull downs on SDI.)

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LTC2622 SDI pin float

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