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FEATURES
“CIickless” Bilateral Audio Switching
Four SPST Switches in a 20-Pin Package
Ultralow THD+N: 0.0008% @ 1 kHz (2 V rms,
R L = 100 k⍀)
Low Charge Injection: 35 pC typ
High OFF Isolation: –100 dB typ (RL = 10 k⍀ @ 1 kHz)
Low Crosstalk: –94 dB typ (R L = 10 k⍀ @ 1 kHz)
Low ON Resistance: 28 ⍀ typ
Low Supply Current: 900 A typ
Single or Dual Supply Operation: +11 V to +24 V or
؎5.5 V to ؎12 V
Guaranteed Break-Before-Make
TTL and CMOS Compatible Logic Inputs
Low Cost-Per-Switch
GENERAL DESCRIPTION
The SSM2404 integrates four SPST analog switches in a single
20-pin package. Developed specifically for high performance
audio applications, distortion and noise are negligible over the
full operating range of 20 Hz to 20 kHz. With very low charge
injection of 35 pC, “clickless” audio switching is possible, even
under the most demanding conditions.
Switch control is realized by conventional TTL or CMOS
logic. Guaranteed “break-before-make” operation assures that
all switches in a large system will open before any switch
reaches the ON state.
Single or dual supply operation is possible. Additional features
include –100 dB OFF isolation, –94 dB crosstalk and 28 Ω ON
resistance. Optional current-mode switching permits an
extended signal-handling range. Although optimized for large
load impedances, the SSM2404 maintains good audio
performance even under low load impedance conditions.
Quad Audio Switch
SSM2404
BLOCK DIAGRAM OF ONE SWITCH CHANNEL
V–
CONTROL
LOGIC INTERFACE
AND
BREAK-BEFORE-MAKE
CONTROL
SW1 A
RAMP
GENERATOR
DIGITAL
CONTROL
SW1 B
V+
PIN CONNECTIONS
Epoxy Mini-DIP (P Suffix)
and SOIC (S Suffix)
SW1 A
1
AGND
2
SW1 B
20
3
AGND
SW4 B
17
SW4
19
18
SW1
SW1
SW4 A
V+
DGND
4
SW1 CONTROL
5
16
SW4 CONTROL
SW2 CONTROL
6
15
SW3 CONTROL
NC*
7
14
V–
SW2 B
8
13
SW3 B
AGND
9
12
AGND
SW2 A
10
11
SW3 A
O
TOP VIEW
(Not to Scale)
SSM2404
SW2
SW3
NC = NO CONNECT
*CONNECT TO ANALOG GROUND
FOR BEST NOISE ISOLATION
REV. B
Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 617/329-4700
Fax: 617/326-8703
