CTW138

Features 

• Low current – 0.5mA 

• Superior CTR-2000% 

• CTR guaranteed 0–70°C 

• Regulatory Approvals 

UL - UL1577 (E364000) 

VDE - EN60747-5-5(VDE0884-5) 

CQC – GB4943.1, GB8898 

IEC60065, IEC60950 

Applications 

• Digital logic ground isolation 

• Telephone ring detector 

• EIA-RS-232C line receiver 

• High common mode noise line receiver 

• Current loop receiver 

Description 

The CTW138 & CTW139 optocouplers consist of an 

AlGaAs LED optically coupled to a high gain split 

darlington photodetector. 

The combination of a very low input current of 

0.5mA and a high current transfer ratio of 2000% 

makes this family particularly useful for input 

interface to MOS, CMOS, LSTTL and EIA RS232C, 

while output compatibility is ensured to CMOS as 

well as high fan-out TTL requirements. 

The devices are packaged in an 8-pin widebody 

package and also available in surface mount lead 

forming option.