MagAlpha MA750 User Manual

NOT RECOMMENDED FOR

NEW DESIGNS

REFER TO MA850

MagAlpha MA750

All MPS parts are lead-free, halogen-free, and adhere to the RoHS directive. For
MPS green status, please visit the MPS website under Quality Assurance. “MPS”
and “The Future of Analog IC Technology” are registered trademarks of
Monolithic Power Systems, Inc.

Contactless Turning Knob Sensor

DESCRIPTION

The MagAlpha MA750 is a robust, contactless,
angle encoder suitable for control buttons and
knobs. The IC detects the absolute angular
position of a permanent magnet, typically a
diametrically magnetized cylinder attached to
the rotor.

The output is digital (SPI) or pulse-width
modulation (PWM). For usual potentiometer
replacement, the PWM signal can be filtered to
obtain an analog signal.

Please See Position Sensor Design Support for All
Supporting Software

TYPICAL APPLICATION

FEATURES

 8-Bit Digital and 12-Bit PWM Output
 500kHz Refresh Rate
 7.5mA Supply Current
 Serial Interface for Data Readout and

Settings

APPLICATIONS

 Potentiometer Replacement
 Knobs
 Dials
 Appliances
 Consumer Goods

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© 2018 MPS. All Rights Reserved.

NOT RECOMMENDED FOR

NEW DESIGNS

REFER TO MA850

MA750 – CONTACTLESS TURNING KNOB SENSOR

Part Number*

Package

Top Marking

MA750GQ

QFN-16 (3mmx3mm)

See Below

y: Year code
O: Optional marking
LLL: Lot number

TOP VIEW

QFN-16 (3mmx3mm)

ORDERING INFORMATION

* For Tape & Reel, add suffix –Z (e.g. MA750GQ–Z)

TOP MARKING

PACKAGE REFERENCE

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© 2018 MPS. All Rights Reserved.

NOT RECOMMENDED FOR

NEW DESIGNS

REFER TO MA850

(2)

NOTES:

1) Exceeding these ratings may damage the device.

2) The maximum allowable power dissipation is a function of the
maximum junction temperature TJ (MAX), the junction-to-

ambient thermal resistance θ

JA

, and the ambient temperature
TA. The maximum allowable continuous power dissipation at
any ambient temperature is calculated by PD (MAX) = (T

J

(MAX)-T

A

)/θ

JA

.

3) Measured on JESD51-7, 4-layer PCB.

(1)

ABSOLUTE MAXIMUM RATINGS

Supply voltage (continuous) ........ -0.5V to +3.8V

Supply voltage short term ........... -0.5V to +4.1V

I/O pin voltage .............................. -0.5V to 3.8V

Continuous power dissipation (TA = +25°C)

.................................................................. 2.5W

MA750 – CONTACTLESS TURNING KNOB SENSOR

Thermal Resistance

QFN-16 (3mmx3mm)..............50 ....... 12 ... °C/W

(3)

θJA θJC

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7/3/2018 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2018 MPS. All Rights Reserved.

NOT RECOMMENDED FOR

NEW DESIGNS

REFER TO MA850

MA750 – CONTACTLESS TURNING KNOB SENSOR

Parameter

Symbol

Condition

Min

Typ

Max

Units

Operating Conditions

Supply voltage

VDD

3.0

3.3

3.6

V

Supply voltage for OTP
flashing

V

flash

3.9

4.0

4.1

V

Supply current for OTP
flashing

(4)

I

flash

50 100

mA

Operating temperature

Top

-40 125

°C

Applied magnetic field

B 30

75 mT

ELECTRICAL CHARACTERISTICS

NOTE:

4) Please see the OTP Programming section for more details about the supply circuits for OTP flashing.

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7/3/2018 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2018 MPS. All Rights Reserved.

NOT RECOMMENDED FOR

NEW DESIGNS

REFER TO MA850

MA750 – CONTACTLESS TURNING KNOB SENSOR

Parameter

Symbol

Condition

Min

Typ

Max

Units

Sensor Output Specifications

Power-up time

(5)

2 3

ms

Supply current

6.0

7.7

8.8

mA

INL at 25°C

At room temperature over the field
range

±0.9

±1.6

±2.0

deg

INL between -40°C to
+125°C

(5)

The largest value over the
temperature range and field range

±0.5

±1.6

±2.5

deg

Output Drift

Temperature induced

(5)

-0.026

+0.026

deg/°C

Magnetic field induced

(5)

-0.023

+0.023

deg/mT

Voltage supply induced

(5)

-0.7

+0.7

deg/V

Absolute Output – Serial

Data output length

8 8

bit

Refresh rate

488

524

558

kHz

Latency

(6)

Measured at constant speed

3

µs

Resolution
(3σ noise level)

Measured by averaging over all
angles

8.0 8.0

bit

Absolute Output – PWM

8

bit

Resolution
(3σ noise level)

12 12

bit

Digital I/O

Threshold voltage high

1.75 V

Threshold voltage low

1.05 V

Rising edge slew rate

CL = 50pF

0.7 V/ns

Falling edge slew rate

CL = 50pF

0.7 V/ns

OTP Flash Timing

Flashing time for one
register

(6)

2.6

ms

Period for multiple
registers flashing

(6)

Time between 2 successive flash
commands

2.6

ms

ELECTRICAL CHARACTERISTICS (continued)

VDD = 3.3V, 50mT < B < 100mT, temp = -40°C to +125°C, unless otherwise noted.

NOTES:

5) Guaranteed by design.

6) Guaranteed by characteristic test.

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7/3/2018 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2018 MPS. All Rights Reserved.

NOT RECOMMENDED FOR

NEW DESIGNS

REFER TO MA850

MA750 – CONTACTLESS TURNING KNOB SENSOR

TYPICAL CHARACTERISTICS

VDD = 3.3V, temp = 25°C, unless otherwise noted

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7/3/2018 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2018 MPS. All Rights Reserved.