DS1050

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OPERATION

Interface protocol is simplified to an 8-bit control byte and 8-bit data byte. Information can be read or

written to the DS1050 including a commanded shutdown operation.

Power-Up Configuration

The DS1050 powers-up to half-scale (10000B) providing 50% duty-cycle. In this mode, the DS1050 can

be used as a standalone oscillator of the frequency specified. Once powered, the PWM output can be

changed via the 2-wire addressable serial port.

Pin Description

from +2.7 volts to +5.5 volts.

GND – Ground terminal.

0% to 96.88%. An additional command sequence will provide a 100% duty cycle or “full-on.”

SCL – Serial clock input.

SDA – Serial bi-directional data I/O.

A0, A1, A2 – Device address (chip selects).

2-Wire Addressable Serial Port Control

The 2-wire serial port interface supports a bi-directional data transmission protocol with device

addressing. A device that sends data on the bus is defined as a transmitter, and a device receiving data as

a receiver. The device that controls the message is called a “master.” The devices that are controlled by

the master are “slaves.” The bus must be controlled by a master device that generates the serial clock

(SCL), controls the bus access, and generates the START and STOP conditions. The DS1050 operates as

a slave on the 2-wire bus. Connections to the bus are made via the open-drain I/O lines SDA and SCL.

The following I/O terminals control the 2-wire serial port: SDA, SCL, A0, A1, and A2. A 2-wire serial

port overview and timing diagrams for the 2-wire serial port can be found in Figures 2 and 5,

respectively. Timing information for the 2-wire serial port is provided in the “AC Electrical

Characteristics” table for 2-wire serial communications.