CMX994 Datasheet, PDF (25/61 Pages) CML Microcircuits – Local Oscillator

Direct Conversion Receivers
CMX994/CMX994A/CMX994E
Notes:
 All registers will retain data if DVDD and VDDIO pins are held high, even if all other power supply pins are
disconnected.
 If clock and data lines are shared with other devices, DVDD and VDDIO must be maintained in their normal
operating ranges otherwise ESD protection diodes may cause a problem with loading the signals connected
to SCLK, CDATA and RDATA pins, preventing correct programming of other devices. Other supplies may be
turned off and all circuits on the device may be powered down without causing this problem.
Single byte from µC (General Reset command)
CSN
SERIAL CLOCK (SCLK)
COMMAND DATA (CDATA)
765432 10
REPLY DATA (RDATA)
Hi-Z ^{Address (10 Hex = Reset)}
Note:
The SERIAL CLOCK line may be high
or low at the start and end of each
transaction.
= Level not important
One Address and one Data byte from µC to CMX994
CSN
SERIAL CLOCK (SCLK)
COMMAND DATA (CDATA)
765432 10
Address
REPLY DATA (RDATA)
Hi-Z
765432 10
Data to CMX994
One Address byte from µC and one Reply byte from CMX994
CSN
SERIAL CLOCK (SCLK)
COMMAND DATA (CDATA)
765432 10
Address
REPLY DATA (RDATA)
Hi-Z
765432 10
Data from CMX994
Figure 16 C-BUS Transactions
7.1 General Reset: $10 (no data)
A command to this register resets the device and clears all bits of all registers. The General Reset command
places the device into powersave mode.
Whenever power is applied to the DVDD pin, a built-in power-on-reset circuit ensures that the device powers
up into the same state as follows a General Reset command. The RESETN pin on the device will also reset the
device to the same state.
 2015 CML Microsystems Plc
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