LMH6521 Datasheet, PDF (18/24 Pages) Texas Instruments – LMH6521 High Performance Dual DVGA

Parameter
t_CSH
t_CSS
t_OZD
t_ODZ
t_OD
FIGURE 12. Read Timing
Read Timing
Data Output on SDO Pin
Description
Chip select hold time
Chip select setup time
Initial output data delay
High impedance delay
Output data delay
30120111
FIGURE 13. Write Timing
Data Written to SDI Pin
30120110
Write Timing
Data Input on SDI Pin
Parameter
t_PL
t_PH
t_SU
t_H
Description
Minimum clock low time (clock duty dycle)
Minimum clock high time (clock duty cycle)
Input data setup time
Input data hold time
PULSE MODE (MOD1= 0, MOD0 = 1)
Pulse mode is a simple yet fast way to adjust gain settings.
Using only two control lines per channel the LMH6521 gain
can be changed by simple up and down signals. Gain step
sizes is selectable either by hard wiring the board or using two
additional logic inputs. For a system where gain changes can
be stepped sequentially from one gain to the next and where
board space is limited this mode may be the best choice. The
ENA and ENB pins are fully active during pulse mode, and
the channel gain state is preserved during the disabled state.
Refer to Digital Control Mode Pin Functions table for pin def-
initions of the LMH6521 in pulse mode.
In this mode the gain step size can be selected from a choice
of 0.5, 1, 2 or 6dB steps. During operation the gain can be
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