Datasheet

MAX4908/MAX4909/MAX4930/MAX4932
Detailed Description
The MAX4908/MAX4909/MAX4930/MAX4932 dual 3:1
clickless audio multiplexers are low 0.38Ω (typ) on-resis-
tance, low 150nA (typ) supply current, high power-sup-
ply rejection ratio (PSRR) devices that operate from a
+1.8V to +5.5V single supply. These devices feature a
negative signal capability that allows signals below GND
to pass through without distortion and break-before-
make switching.
The MAX4908/MAX4909/MAX4930/MAX4932 use two
digital control bits CB1 and CB2 to switch between sig-
nals (see Table 1). The MAX4908 has shunt resistors on
all the unselected terminals to suppress click-and-pop
sounds that may occur from switching to a pre-charged
terminal. The MAX4909 does not have click-and-pop
suppression resistors on X0 and Y0 terminals for appli-
cations that do not require predischarge switching. The
MAX4930 only has shunt resistors on X2 and Y2 termi-
nals. The MAX4932 has no shunt resistors on all termi-
nals.
Applications Information
Digital Control Inputs
The MAX4908/MAX4909/MAX4930/MAX4932 logic
inputs accept up to +5.5V regardless of supply voltage.
For example, with a +3.3V supply, CB_ can be driven
low to GND and high to +5.5V, allowing for mixing of
logic levels in a system. Driving CB_ rail-to-rail mini-
mizes power consumption. For a +3.3V supply voltage,
the logic thresholds are +0.5V (low) and +1.4V (high).
Analog Signal Levels
The MAX4908/MAX4909/MAX4930/MAX4932 have a low
on-resistance of 0.38Ω (typ) and the on-resistance flat-
ness is guaranteed over temperature and will show
minimal variation over the entire voltage supply range
(see the
Typical Operating Characteristics ). The on-
resistance flatness and low-leakage features make it
ideal for bidirectional operation. The switches are bidi-
rectional, so X_, Y_, and common terminals X and Y
pins can be either inputs or outputs.
These devices pass signals as low as V
CC
- 5.5V,
including signals below ground with minimal distortion.
Dual 3:1 Clickless Audio Multiplexers
with Negative-Signal Handling
6 _______________________________________________________________________________________
Table 1. Truth Table
CB1
CB2
COMMON X COMMON Y
0 0 High Impedance High Impedance
0 1 Connected to X0 Connected to Y0
1 0 Connected to X1 Connected to Y1
1 1 Connected to X2 Connected to Y2
Pin Description
PIN
TDFN-EP
WLP
NAME FUNCTION
1B4V
CC
Positive Supply Voltage Input
2 C4 X Analog Output X Common Terminal
3,10 — N.C. No Connection. Not internally connected.
4 C3 X2 Analog Input X2
5 C2 X1 Analog Input X1
6 B2 CB1 Digital Control Input 1
7 C1 X0 Analog Input X0
8 B1 GND Ground
9 A1 Y0 Analog Input Y0
11 A2 Y1 Analog Input Y1
12 A3 Y2 Analog Input Y2
13 B3 CB2 Digital Control Input 2
14 A4 Y Analog Output Y Common Terminal
— — EP Exposed Pad. Connect to ground or leave unconnected.