© Semiconductor Components Industries, LLC, 2001

April, 2001 – Rev. 0

1

Publication Order Number:

AND8058/D

AND8058/D

Two New Analog Switches

Set Standards for Space

Efficiency

Prepared by: Fred Zlotnick

ON Semiconductor

INTRODUCTION

Analog switches that provide analog and digital switching

to circuit designers, have been around for more than

30 years. One of the most popular switches has been the

4053, a triple Single–Pole Double–Throw (SPDT) switch in

a 16–pin package. The most aggressive common package

The hand–held wireless phenomenon is driving the need

to get more functionality into even smaller spaces. In

response,

ON

Semiconductor

released

more

than

30 single–gate switches that supply exactly the right bit of

logic just where it is needed. These products were released

in industry standard SC88A/SOT–353 packages which

provide standard logic functions. An example is the

MC74VHC1G66, a Single–Pole, Single–Throw (SPST)

analog switch.

The NLAS4599

The new NLAS4599 device is a single SPDT switch,

one–third the size of the venerable 4053, contained in an

aggressive 0.6

µ CMOS technology. It provides voltage

frequency response. The NLAS4599 sets a new standard in

functionality as one–third of a 4053. Compared to the 4053,

the NLAS4599 is 2.5 times more space efficient. This is a

real boon to designers, who need to put as much

functionality as possible into every square inch.

Examples

1. Design a crystal–controlled oscillator that functions

at 32 KHz for minimum power consumption and

16 MHz for performance in a battery–operated

environment. The new NL27WZU04 provides two

gate is an oscillator; the second gate is a buffer. The

NLAS4599 is used to switch crystals. A single

control line (assumed to come from a

microcontroller) controls the frequency. When the

unit is near idle, the clock is 32 KHz and the

microcontroller/DSP functions at minimum power

consumption. When speed (performance) is

required, the clock switches to 16 MHz.

GND

CTRL

NLAS4599

GND

32 kHz

16 MHz

12 p

12 p

12 M

Ω

1/2 NL7WZU04

OSC OUT

Figure 1. Dual Frequency Oscillator

10 K

This circuit provides dual clock rates under microprocessor control and occupies minimal board space.

http://onsemi.com

APPLICATION NOTE