Analog Devices Inc. ADM3312EARU

Triple Transmitter/Receiver RS-232 24-Pin TSSOP Tube
The ADM3312E is a three-driver/three-receiver serial port transceiver, which meets full EIA-232 standards while operating from a single power supply as low as 2.7V. It features an on-board, charge pump dc-to-dc converter, which eliminates the need for dual power supplies. This dc-to-dc converter also contains a voltage tripler and voltage inverter for internally generating positive and negative supplies from the power supply. It operates in Green Idle Mode, where the charge pump oscillator is gated on and off to maintain output voltage to /-7.25 V, regardless of the load conditions. Another key feature is its ESD protection: up to /-15kV on all I/O lines. The ADM3312E is available in a 24-pin TSSOP package as well as a space-saving 32-pin LFCSP package. APPLICATIONS Mobile phone handsets/data cables Laptop and notebook computers Printers Peripherals Modems PDAs/Hand-Held Devices/Palmtop Computers
The ADM33xxE line of driver/receiver products is designed to fully meet the EIA-232 standard while operating with a single 2.7 V to 3.6 V power supply. The devices feature an on-board charge pump dc-to-dc converter, eliminating the need for dual power supplies. This dc-to-dc converter contains a voltage tripler and a voltage inverter that internally generates positive and negative supplies from the input 3 V power supply. The dcto-dc converter operates in Green Idle mode, whereby the charge pump oscillator is gated on and off to maintain the output voltage at -7.25 V under varying load conditions. This minimizes the power consumption and makes these products ideal for battery-powered portable devices. The ADM33xxE devices are suitable for operation in harsh electrical environments and contain ESD protection up to -15 kV on their RS-232 lines (ADM3310E, ADM3311E, ADM3312E, and ADM3315E). The ADM3307E contains ESD protection up to -15 kV on all I/O lines (CMOS, RS-232, EN, and SD). A shutdown facility that reduces the power consumption to 66 nW is also provided. While in shutdown, one receiver remains active (two receivers active with ADM3310E), thereby allowing monitor-ing of peripheral devices. This feature allows the device to be shut down until a peripheral device begins communication. The active receiver can alert the processor, which can then take the ADM33xxE device out of the shutdown mode. The ADM3307E contains five drivers and three receivers and is intended for mobile phone data lump cables and portable computing applications. The ADM3311E contains three drivers and five receivers and is intended for serial port applications on notebook/laptop computers. The ADM3310E is a low current version of the ADM3311E. This device also allows two receivers to be active in shutdown mode. The ADM3312E contains three drivers and three receivers and is intended for serial port applications, Pd As, mobile phone data lump cables, and other hand-held devices. The ADM3315E is a low current version of the ADM3312E, with a 22 kOmega receiver input resistance that reduces the drive requirements of the DTE. Its main applications are Pd As, palmtop computers, and mobile phone data lump cables. The ADM33xxE devices are fabricated using CMOS technology for minimal power consumption. All parts feature a high level of over voltage protection and latch-up immunity. All ADM33xxE devices are available in a 32-lead 5 mm * 5 mm LFCSP_VQ and in a TS SOP (ADM3307E, ADM3310E, and ADM3311E in a 28-lead TSSOP; ADM3312E and ADM3315E in a 24-lead TSSOP). The ADM3311E also comes in a 28-lead SSOP. The ADM33xxE devices are ruggedized RS-232 line drivers/receivers that operate from a single supply of 2.7 V to 3.6 V. Step-up voltage converters coupled with level shifting transmitters and receivers allow RS-232 levels to be developed while operating from a single supply. Features include low power consumption, Green Idle operation, high transmission rates, and compatibility with the EU directive on electromagnetic compatibility. This EM compatibility directive includes protection against radiated and conducted interference, including high levels of electrostatic discharge. All RS-232 (and CMOS, SD, and EN for ADM3307E) inputs and outputs are protected against electrostatic discharges (up to -15 kV). This ensures compliance with IEC 1000-4-2 requirements. These devices are ideally suited for operation in electrically harsh environments or where RS-232 cables are frequently being plugged/unplugged. They are also immune to high RF field strengths without special shielding precautions. Emissions are also controlled to within very strict limits. CMOS technology is used to keep the power dissipation to an absolute minimum, allowing maximum battery life in portable applications.