MAX14504 Datasheet, PDF (10/12 Pages) Maxim Integrated Products – Internal Shunt Switches Reduce Click/Pop

Dual SPDT Negative Rail Analog Switches
with ±V_CC Capability
Digital Control Inputs
The MAX14504/MAX14505/MAX14505A/MAX14506
logic inputs accept up to +5.5V, regardless of supply
voltage. For example, with a +3.3V supply, CB and EN
can be driven low to GND and high to +5.5V, allowing
for mixed logic levels in a system. Using logic levels of
V_IL = 0 to V_IH ≥ V_CC reduces supply current.
Analog Signal Levels
These devices pass signals from -V_CC to +V_CC with
minimal distortion and very little change in on-resistance
(see the Typical Operating Characteristics). The switch-
es are bidirectional; therefore, the NO_, NC_, and COM_
terminals can be used as either inputs or outputs.
Click-and-Pop Suppression
The MAX14505/MAX14505A have a shunt switch on
NO1 and NO2 terminals to automatically discharge any
capacitance when they are not connected to COM1
and COM2. The shunt switch reduces audible click-
and-pop sounds that occur when switching between
capacitively coupled audio sources. Audible clicks and
pops are caused when a step DC voltage is switched
into the speaker. The DC step transients are reduced
by automatically discharging the side that is not con-
nected to the COM terminal, reducing any residual DC
voltage and reducing clicks and pops.
Applications Information
Power-Supply Sequencing
Proper power-supply sequencing is recommended for
all CMOS devices. Improper supply sequencing can
force the switch into latch-up, causing it to draw exces-
sive supply current. The only way out of latch-up is to
remove all signals and power and then reapply properly.
Connect all ground pins first, apply power to V_CC, and
finally apply signals to NO_, NC_, and COM_. Follow the
reverse order upon power-down.
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