HAL815 datasheet(19/24 Pages) MICRONAS

19 / 24 page

ADVANCE INFORMATION

HAL 815

Micronas

5. Programming of the Sensor

5.1. Definition of Programming Pulses

The sensor is addressed by modulating a serial tele-

gram on the supply voltage. The sensor answers with

a serial telegram on the output pin.

The bits in the serial telegram have a different bit time

for the VDD-line and the output. The bit time for the

VDD-line is defined through the length of the Sync Bit

at the beginning of each telegram. The bit time for the

output is defined through the Acknowledge Bit.

A logical “0” is coded as no voltage change within the

bit time. A logical “1” is coded as a voltage change

between 50% and 80% of the bit time. After each bit, a

voltage change occurs.

5.2. Definition of the Telegram

Each telegram starts with the Sync Bit (logical 0), 3

bits for the Command (COM), the Command Parity Bit

(CP), 4 bits for the Address (ADR), and the Address

Parity Bit (AP).

There are 4 kinds of telegrams:

– Write a register (see Fig. 5–2)

After the AP Bit, follow 14 Data Bits (DAT) and the

Data Parity Bit (DP). If the telegram is valid and the

command has been processed, the sensor answers

with an Acknowledge Bit (logical 0) on the output.

– Read a register (see Fig. 5–3)

After evaluating this command, the sensor answers

with the Acknowledge Bit, 14 Data Bits, and the

Data Parity Bit on the output.

– Programming the EEPROM cells (see Fig. 5–4)

After evaluating this command, the sensor answers

with the Acknowledge Bit. After the delay time tw,

the supply voltage rises up to the programming volt-

age.

– Activate a sensor (see Fig. 5–5)

If more than one sensor is connected to the supply

line, selection can be done by first deactivating all

sensors. The output of all sensors will be pulled to

ground by the internal 10 k

Ω resistors. With an Acti-

vate pulse on the appropriate output pin, an individ-

ual sensor can be selected. All following commands

will only be accepted from the activated sensor.

Fig. 5–1: Definition of logical 0 and 1 bit

tp0

logical 0

VDDH

VDDL

tp0

logical 1

VDDH

VDDL

tp0

tp1

Table 5–1: Telegram parameters

Symbol

Parameter

Min.

Typ.

Max.

Unit

Remarks

VDDL

Supply Voltage for Low Level

during Programming

5.6

VDDH

Supply Voltage for High Level

during Programming

16.8

8.0

8.5

Rise time

0.05

Fall time

0.05

tp0

Bit time on VDD

1.7

1.75

1.8

tp0 is defined through the Sync Bit

tpOUT

Bit time on output pin

tpOUT is defined through the

Acknowledge Bit

tp1

Voltage Change for logical 1

1, 3

% of tp0 or tpOUT

VDDPROG

Supply Voltage for

Programming the EEPROM

11.95

12.1

tPROG

Programming Time for EEPROM

100

105

HAL815 Datasheet(PDF) 19 Page - Micronas

HAL815 Datasheet(HTML) 19 Page - Micronas

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Datasheet Download

Link URL