DESCRIPTION
The LH1529A and LH1529B Telecom switches consist of an optically coupled solid state relay (SSR) and a bidirectional input optocoupler. The SSR is ideal for performing switchhook and dial-pulse switching while the optocoupler performs ring detection and loop current sensing functions. Both the SSR and optocoupler provide 5300 VRMS of input to output isolation.
The SSR is integrated on a monolithic receptor die using high voltage technology. The optocoupler provides bidirectional current sensing via two antiparallel GaAs infrared emitting diodes. The opto channel provides a minimum CTR of 33% at 6.0 mA.

FEATURES
• Solid State Relay and Optocoupler in One Package
• Surface Mount Package
• l/O Isolation, 5300 VRMS
• LH1529A, CTR Min.=33%
• LH1529B, CTR Min.=100%
• Flammability; UL94,VØ
• Optocoupler
   – Bidirectional Current Detection
• Solid-state Relay
   – See LH1540 Data Sheet
   – Typical RON 20 Ω
   – Load Voltage 350 V
   – Load Current 120 mA
   – Current Limit Protection

AGENCY APPROVALS
• UL – File No. E52744
• BSI/BABT Cert. No. 7980
• FIMKO Approval

APPLICATIONS
• General Telecom Switching
   – On/off Hook Control
   – Dial Pulse
   – Ring Current Detection
   – Loop Current Sensing
• See Appnote 56