Specifications

Product Technical Specification & Customer Design Guidelines
Interfaces
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WA_DEV_Q64_PTS_001-003 January 9, 2009
3.7.3 Application
The voltage level shifter must be set at 2.8V and compliant with a V28 electrical
signal.
Figure 8: Example of RS-232 level shifter implementation for UART2
Recommended components:
Capacitors
 C1 : 220nF
 C2, C3, C4 : 1μF
Inductor
 L1 : 10μH
RS-232 Transceiver
 U1 : LINEAR TECHNOLOGY LTC2802IDE
 J1 : SUB-D9 female
The LTC2802 can be powered by an external regulator at 2.8 V.
The UART2 interface can be connected directly to others components if the voltage
interface is 2.8 V.