MLX90821

Relative Pressure Sensor IC

Page 9 of 40

REV 004 – 4 MAR 2021

3901090821

A broken wire detection block allows actively driving the output to one of the rails in case of a broken supply

or ground connection. Extensive protection of the supply lines allows the MLX90821 to handle extreme

overvoltage conditions and is immune to severe external disturbances. Several diagnostic functions (over -

voltage, under-voltage, overpressure, under pressure detections) have been implemented on the 90821 and

can be enabled by programming EEPROM settings. Figure 3 describes MLX90821 block diagram.

Analog

Output

Piezoresistive

sensing element

Overvoltage &

reverse voltage

protection

Voltage regulator

POR

Gnd

Vsupply

Test

Vbrg

InP

InN

Test

On chip temperature

sensor

OPA

ADC

M

U

X

InP, InN, VEXT

PGA

16 bits

DSP

Rom

Pressure Linearization

Gain & Offset

Temperature

Compensation

Programmable Filter

Vana

Oscillator

EEPROM

Ram

Sensor bias

Off chip temperature

sensor current output

IV conversion

6/7 VDDA

Divided bridge

current

DAC

Gain

12 bits

External NTC

interface

SENT

Output

NTC

Input

Figure 3: MLX90821 block diagram