The SN65C3243 and SN75C3243DW consist of three line drivers, five line receivers, and a dual charge-pump circuit with ±15-kV ESD protection pin to pin (serial-port connection pins, including GND). This device provides the electrical interface between an asynchronous communication controller and the serial-port connector. The charge pump and four small external capacitors allow operation from a single 3-V to 5.5-V supply. In addition, this device includes an always-active noninverting output (ROUT2B), which allows applications using the ring indicator to transmit data while the device is powered down. The device operates at data signaling rates up to 1 Mbit/s and an increased slew-rate range of 24 V/μs to 150 V/μs.
Flexible control options for power management are available when the serial port is inactive. The auto-powerdown feature functions when FORCEON is low and INVALID is low (invalid data) if all receiver input voltages are between –0.3 V and 0.3 V for more than 30 μs. Refer to Figure 5 for receiver input levels.
Feature
- Operates With 3-V to 5.5-V VCC Supply
- Always-Active Noninverting Receiver Output (ROUT2B)
- Low Standby Current . . . 1 μA Typ
- External Capacitors . . . 4 × 0.1 μF
- Accepts 5-V Logic Input With 3.3-V Supply
- Inter-Operable With SN65C3238, SN75C3238
- Supports Operation From 250 kbit/s to 1 Mbit/s
- RS-232 Bus-Pin ESD Protection Exceeds ±15 kV Using Human-Body Model (HBM)
- Latch-Up Performance Exceeds 100 mA Per JESD 78, Class II
- APPLICATIONS
- Battery-Powered Systems
- PDAs
- Notebooks
- Laptops
- Palmtop PCs
- Hand-Held Equipment
