Bit

Type

Description

1

R/W

Shutdown (Shutdown Mode). When set to "1" this bit stops the operation of all functions and places the

device in the lowest power consumption mode.

0: Device in Active Mode. (default)

1: Device in Shutdown Mode.

2

R/W

LowPwr (Low-Power Mode). When set to "1" this bit slows the operation of all functions and places the

device in a low power consumption mode. In Low-Power Mode, the conversion rate of the LM95010 is

effected see Section 2.10 for further details.

0: Device in Active Mode. (default)

1: Device in Low-Power Mode.

3RO

Not supported. Will always read "0".

4

R/W

EnF1 (Enable Function 1). When bit is set to "1" this bit Function 1 is enabled for operation. A function may

require setup before this bit is set. The function registers can be accessed even when the function is

disabled.

0: Function 1 is disabled. (default)

1: Function is enabled.

15-5

RO

Not supported. Will always read "0".

2.9 TEMPERATURE MEASUREMENT FUNCTION (TYPE - 0001)

This section defines the register structure and operation of a Temperature Measurement function as it applies to the LM95010.

The FuncDescriptor value of this function is ‘0001’.

2.9.1 Operation

The Temperature Measurement function as implemented in the LM95010 supports one temperature zone, the LM95010’s internal

temperature (LM95010’s junction temperature). Since the LM95010 only supports one temperature measurement the Sensor

Scan function as defined in the SensorPath specification only applies to one temperature sensor. A temperature scan is enabled

by the SensorEnable bit (EN0). The minimum scan rate is recommended to be 4Hz (i.e. the measurement data is updated at least

once in 250 ms), see Section 2.10 for further details. In Low-Power Mode, the scan rate is four time lower than the scan rate in

Active Mode. The scan rate effects the bus bandwidth required to read the results. The sampling rate of the temperature

measurements can also be controlled via the Conversion Rate register, see Section 2.10 for further details.

Data Readout

When a new result is stored in the Readout register a Function Event is generated. Reading the Readout

register clears the Status Function 1 flag (SF1). The result is available in the Readout register waiting for the master to read it

during the master sensor read sequence. If a new result is ready before the previous result has been read, the new result

overwrites the previous result and the Error Function 1 flag (ERF1) is set (indicating an overrun event). Reading the Readout

register clears also the Error Function 1 flag (ERF1). The Readout register contains the temperature data, and the sensor number.

Since the LM95010 only supports one temperature zone the sensor number field will always report zero. Other fields in the

Readout register as defined by the SensorPath specification are not supported.

Readout Resolution

The resolution of the readout is defined in the Temperature Capabilities register. The resolution of the

LM95010 is fixed and cannot be modified by software.

Function Event

The Temperature Measurement function generates a Function Event whenever a temperature conversion

cycle is completed and new data is stored in the Readout Register. When the new data is stored into the Readout register the SF1

bit in the device Status register is set to "1" and remains set, until it is cleared by reading the Readout register. An Attention

Request is generated on the bus, only if it is enabled by the Attention Enable bit (ATE) in the Temperature Control register.

Setup Before Enabling

No setup is required for the Temperature Measurement function before the function is enabled.

2.9.2 Temperature Capabilities (Addr 10o)

Reg

Add

Register

Name

R/

W

P

O

R

Val

Bit

15

MSb

Bit

14

Bit

13

Bit

12

Bit

11

Bit

10

Bit

9

Bit

8

Bit

7

Bit

6

Bit

5

Bit

4

Bit

3

Bit

2

Bit

1

Bit

0

LSb

001 000

Temperature

Capabilities

R 014Ah

Reserved

Int

Sens

Rout

Size

Sign

10Bits

0.25˚C

Resolution

0000000101001010

This register defines the format of the temperature data in the readout register. The LM95010 only supports one format as defined

by the values of this register.

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