Datasheet

MAX19707
10-Bit, 45Msps, Ultra-Low-Power
Analog Front-End
20 ______________________________________________________________________________________
Figure 5. Tx DAC System Timing Diagram
t
DSQ
t
DSI
Q: N - 2 I: N - 1
D0–D9
CLK
ID
QD
Q: N - 1
I: N
Q: N I: N + 1
N - 2
N - 1
N
N - 2
N - 1
N
t
DHQ
t
DHI
Tx DAC Timing
Figure 5 shows the relationship between the clock, input
data, and analog outputs. Data for the I channel (ID) is
latched on the falling edge of the clock signal, and Q-
channel (QD) data is latched on the rising edge of the
clock signal. Both I and Q outputs are simultaneously
updated on the next rising edge of the clock signal.
3-Wire Serial Interface and
Operation Modes
The 3-wire serial interface controls the MAX19707 oper-
ation modes as well as the three 12-bit aux-DACs and
the 10-bit aux-ADC. Upon power-up, program the
MAX19707 to operate in the desired mode. Use the 3-
wire serial interface to program the device for shut-
down, idle, standby, Rx, Tx, aux-DAC controls, or
aux-ADC conversion. A 16-bit data register sets the
mode control as shown in Table 3. The 16-bit word is
composed of A3–A0 control bits and D11–D0 data bits.
Data is shifted in MSB first (D11) and LSB last (A0).
Tables 4, 5, and 6 show the MAX19707 operating
modes and SPI commands. The serial interface remains
active in all modes.
SPI Register Description
Program the control bits, A3–A0, in the register as shown
in Table 3 to select the operating mode. Modify A3–A0
bits to select from ENABLE-16, Aux-DAC1, Aux-DAC2,
Aux-DAC3, IOFFSET, QOFFSET, Aux-ADC, ENABLE-8,
and COMSEL modes. ENABLE-16 is the default operat-
ing mode. This mode allows for shutdown, idle, and
standby states as well as switching between FAST,
SLOW, Rx, and Tx modes. Table 4 shows the MAX19707
power-management modes. Table 5 shows the T/R pin-
controlled external Tx-Rx switching modes. Table 6
shows the SPI-controlled Tx-Rx switching modes.