![]() |
Electronic Components Datasheet Search |
|
AN158 Datasheet(PDF) 1 Page - Macronix International |
|
AN158 Datasheet(HTML) 1 Page - Macronix International |
1 / 3 page ![]() INTERFACE CIRCUITS Jul 09, 1998 Serial-Data Interface Chip Supplies Bipolar Voltages Some of the interface ICs currently available for serial-data transmission not only operate from low VCC levels (5V or 3.3V); they also generate bipolar dc voltages (±6.5V to ±10V) to support the minimum driver-output levels as specified by EIa/TIa-232. With care, you can steal useful amounts of power from these voltage rails without interfering with the IC's operation. In Figure 1, the IC's switch-mode controller operates with an external inductor, two diodes, and two capacitors to produce ±6.5V. FETs Q1 and Q2 ensure start-up for the circuit by disconnecting the load until these switch-mode supply voltages are present. Note that Q1 must be a logic-level device. |