7

FN6356.2

June 11, 2007

Detailed Description

The ISL54050 is a bidirectional, dual single pole/double

throw (SPDT) analog switch that offers precise switching

capability from a single 1.65V to 4.5V supply with low

ON-resistance (0.29

Ω) and high speed operation

suited for portable battery powered equipment due to its low

operating supply voltage (1.65V), low power consumption

(4.5

μW max), low leakage currents (195nA max), and the tiny

flatness provide very low insertion loss and distortion to

applications that require signal reproduction.

External V+ Series Resistor

For improved ESD and latch-up immunity, Intersil

recommends adding a 100

Ω resistor in series with the V+

power supply pin of the ISL54050 IC (see Figure 8).

During an overvoltage transient event, such as occurs during

system level IEC 61000 ESD testing, substrate currents can

be generated in the IC that can trigger parasitic SCR

structures to turn ON, creating a low impedance path from

the V+ power supply to ground. This will result in a

significant amount of current flow in the IC, which can

potentially create a latch-up state or permanently damage

the IC. The external V+ resistor limits the current during this

over-stress situation and has been found to prevent latch-up

or destructive damage for many overvoltage transient

events.

IC produces an insignificant voltage drop across the 100

Ω

series resistor resulting in no impact to switch operation or

performance.

FIGURE 4. OFF ISOLATION TEST CIRCUIT

FIGURE 6. CROSSTALK TEST CIRCUIT

FIGURE 7. CAPACITANCE TEST CIRCUIT

ANALYZER

SIGNAL

GENERATOR

V+

C

0V or V+

NO or NC

COM

IN

GND

Signal direction through switch is reversed, worst case values

are recorded. Repeat test for all switches.

V+

C

0V or V+

NO or NC

COM

IN

GND

100mA

Repeat test for all switches.

0V or V+

ANALYZER

V+

C

NO or NC

SIGNAL

GENERATOR

GND

COM

50

Ω

N.C.

COM

NC or NO

Signal direction through switch is reversed, worst case values

are recorded. Repeat test for all switches.

V+

C

GND

NO or NC

COM

IN

IMPEDANCE

ANALYZER

0V or V+

Repeat test for all switches.

ISL54050