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AS5048A/AS5048B

Magnetic Rotary Encoder

14-bit Angular Position Sensor

Datasheet

4.3

I²C interface

The AS5048B supports 2-wire high-speed I²C protocol in device mode. The host MCU (master) has to initiate the data

transfers. The 7-bit device address of the slave depends on the state of the OTP I2C register 21 (0x15) bit 0…4 + 2 I2C

address selection pin 3 and 4.

Supported modes:

Random/Sequential Read

Byte/Page Write

Standard : 0 to 100kHz clock frequency (slave mode)

Fast Mode : 0 to 400kHz clock frequency (slave mode)

High Speed: 0 to 3.4MHz clock frequency (slave mode)

The SDA signal is bidirectional and is used to read and write the serial data. The SCL signal is the clock generated by the

host MCU, to synchronize the SDA data in read and write mode. The maximum I²C clock frequency is 3.4MHz, data are

triggered on the rising edge of SCL.

4.3.1

I²C Electrical Specification

FS-mode+

HS-mode

HS-mode

Symbol

Parameter

Condition

Min

Max

Min

Max

Min

Max

Unit

LOW-Level Input Voltage

-0.5

-0.5

0.3VDD

-0.5

V

HIGH-Level Input Voltage

(1)

VDD +

0.5 (1)

0.7VDD

(1)

V

Hysteresis of Schmitt Trigger

Inputs

--

--

0.1VDD

--

V

LOW-Level Output Voltage

(open-drain or open-collector)

at 3mA Sink Current

--

--

0.2VDD

--

V

LOW-Level Output Current

20

--

--

--

--

mA

Pull-up current of SCLH

current source

--

--

3

12

3

12

mA

Pulse Width of Spikes that

must be suppressed by the

Input Filter

--

50 (2)

--

10

--

10

ns

Input Current at each I/O Pin

Input Voltage

between

-10

+10 (3)

--

10

--

10

A

Total Capacitive Load for

each Bus Line

--

550

--

100

--

400

pF

I/O Capacitance (SDA, SCL)

--

10

--

10

--

10

pF

Table 14 I²C Ele ctic al Spe cific ation

(2) Input filters on the SDA and SCL inputs suppress noise spikes of less than 50 ns.

(3) I/O pins of Fast-mode and Fast-mode Plus devices must not obstruct the SDA and SCL lines if VDD is switched

off.