MAX1452 データシートの表示（PDF） - Maxim Integrated

部品番号

コンポーネント説明

メーカー

MAX1452

Low-Cost Precision Sensor Signal Conditioner

Maxim Integrated 

MAX1452

Low-Cost Precision Sensor

Signal Conditioner

Pin Description (continued)

PIN

SSOP/TSSOP

TQFN-EP

9

11

10

12

11

14

12

15

13

17

14

18

15

19

16

21

—

—

NAME

FUNCTION

VDDF

UNLOCK

DIO

CLK1M

AMPOUT

AMP-

AMP+

FSOTC

EP

Positive Supply Voltage for EEPROM. Connect a 1µF capacitor from

VDDF to VSS. Connect VDDF to VDD or for improved noise performance

connect a 30Ω resistor to VDD.

Secure-Lock Disable. Allows communication to the device.

Digital Input Output. DIO allows communication with the device.

1MHz Clock Output. The output can be controlled by a configuration bit.

Uncommitted Amplifier Output

Uncommitted Amplifier Negative Input

Uncommitted Amplifier Positive Input

Full Span TC Buffered Output

Exposed Pad (TQFN Only). Internally connected; connect to VSS.

Detailed Description

The MAX1452 provides amplification, calibration, and

temperature compensation to enable an overall perfor-

mance approaching the inherent repeatability of the sen-

sor. The fully analog signal-path introduces no quantiza-

tion noise in the output signal while enabling digitally con-

trolled trimming with the integrated 16-bit DACs. Offset

and span can be calibrated to within ±0.02% of span.

The MAX1452 architecture includes a programmable

sensor excitation, a 16-step programmable-gain ampli-

fier (PGA), a 768-byte (6144 bits) internal EEPROM,

four 16-bit DACs, an uncommitted op amp, and an on-

chip temperature sensor. The MAX1452 also provides a

unique temperature compensation strategy for offset TC

and FSOTC that was developed to provide a remarkable

degree of flexibility while minimizing testing costs.

The customer can select from one to 114 temperature

points to compensate their sensor. This allows the

latitude to compensate a sensor with a simple first order

linear correction or match an unusual temperature curve.

Programming up to 114 independent 16-bit EEPROM

locations corrects performance in 1.5°C temperature

increments over a range of -40°C to +125°C. For sensors

that exhibit a characteristic temperature performance,

a select number of calibration points can be used with

a number of preset values that define the temperature

curve. In cases where the sensor is at a different tempera-

ture than the MAX1452, the MAX1452 uses the sensor

bridge itself to provide additional temperature correction.

The single pin, serial Digital Input-Output (DIO) communi-

cation architecture and the ability to timeshare its activity

with the sensor’s output signal enables output sensing

and calibration programming on a single line by paral-

lel connecting OUT and DIO. The MAX1452 provides a

Secure-Lock feature that allows the customer to prevent

modification of sensor coefficients and the 52-byte user

definable EEPROM data after the sensor has been

calibrated. The Secure-Lock feature also provides a hard-

ware override to enable factory rework and recalibration

by assertion of logic high on the UNLOCK pin.

The MAX1452 allows complete calibration and sensor

verification to be performed at a single test station. Once

calibration coefficients have been stored in the MAX1452,

the customer can choose to retest in order to verify per-

formance as part of a regular QA audit or to generate final

test data on individual sensors.

The MAX1452’s low current consumption and the integrat-

ed uncommitted op amp enables a 4–20mA output signal

format in a sensor that is completely powered from a 2-wire

current loop. Frequency response can be user-adjusted

to values lower than the 3.2kHz bandwidth by using the

uncommitted op amp and simple passive components.

The MAX1452 (Figure 1) provides an analog amplification

path for the sensor signal. It also uses an analog architec-

ture for first-order temperature correction. A digitally con-

trolled analog path is then used for nonlinear temperature

correction. Calibration and correction is achieved by vary-

ing the offset and gain of a programmable-gain-amplifier

(PGA) and by varying the sensor bridge excitation current

www.maximintegrated.com

Maxim Integrated │  6

Share Link: