LTC221 - Micropower, Low Charge Injection, Quad CMOS Analog Switches with Data Latches

The LTC221 and LTC222 are micropower, quad CMOS analog switches which typically dissipate only 250µW from ±15V supplies and 40µW from a single 5V supply. Onboard latches allow the LTC221 and LTC222 to interface directly to most microprocessor buses. The switches have 65 Ohms typical on resistance and a very high off resistance. A break before make characteristic is inherent in these switches to prevent the shorting of two channels. The signal range is ±15V with a supply voltage of ±15V and 0V to 5V with a single 5V supply. The switches have special charge compensation circuitry which greatly reduces charge injection to a maximum of ±25pC (±15V supplies).

The LTC221 and LTC222 are designed for applications such as microprocessor controlled programmable gain amplifiers, automatic test equipment, communication systems, and data acquisition systems. The LTC221 is normally closed and the LTC222 is normally open as shown in the Logic Table.

Features

Micropower Operation
Single 5V or ±15V Supply Operation
Low Charge Injection
Low RON
Low Leakage
Guaranteed Break Before Make
Latch Resistant Design
TTL/CMOS Compatible
Improved Second Source for DG221/DG222
Microprocessor Bus Compatible

Typical Application

Applications

Supply Current.................. I+ = 40µA, I- = 5µA Max
Charge Injection ±15V Supplies.................. �25pC MaxSingle 5V Supply.................. 2pC Typ
RON................... 65 Ohms Typ
Signal Range.................... ±15V