TOA Electronics FPS-T1U, FPS1000-24, FPS1000-12, FPS1000-32, FPS-S1U I2C BUS Interface Option

FPS1000 Instruction Manual

CHAPTER 7 I2C BUS INTERFACE OPTION

7.1 Introduction

The I2C interface option includes facilities to monitor operating parameters of the power supply. The parameters are then transferred to the host PC if demanded, over a standard I2C bus.

The following data can be monitored for the individual units connected to the I2C bus:

1.Status of the unit.

2.Actual output voltage, output current and internal temperature of the unit.

3.Manufacturing related data (model, serial number, manufacturing date etc…).

7.1.1 Addressing (A0, A1, A2).

Three address lines allow up to eight FPS1000 units to be addressed on a single I2C bus. The address lines are internally pulled-up to +5V by resistors. Addressing of a unit is achieved by hard-wiring an address line to the -Sense to set it to "0" or leaving the address line open to set it to "1".

7.1.2 Serial clock

This line is clocked by the processor which controls the I2C bus. It should be connected to +5V (referenced to -Sense) via a pull-up resistor of 2KΩ. The I2C interface is designed to run with a serial clock speed of 100KHz.

7.1.3Serial dataThis line is a bidirectional data line. It should be connected to +5V (referenced to -Sense) via a pull-up resistor of 2KΩ.

7.2 I2C Interface Specifications
7.2.1 General specifications
1.	Clock frequency:	100KHz
2. Address lines:		Three (A0, A1, A2). Support 8 power supply modules
7.2.2 Output voltage measurement
1.	Measurement accuracy:	+/-2% of full scale
2.	Measurement resolution:	8 bits
3.	Measurement range:	0~60.0V for 48V model / 0~40.0V for 32V model / 0-30.0V for 24V model.
7.2.3 Output current measurement
1.	Measurement accuracy:	+/-10% of full scale
2.	Measurement resolution:	8 bits
3.	Measurement range:	0~25.0A for 48V model / 0~50A for 32V & 24V models
7.2.4 Internal temperature measurement		+/-3°C
1.	Measurement accuracy:
2.	Measurement resolution:	8 bits
3.	Measurement range:	0-100°C
7.2.5 EEPROM
1.	EEPROM type:	AT24C02AN-10S , Atmel, or equivalent
2.	EEPROM data:	Model name, Serial no., Revision, Manufacture. Name, Output voltage,
		Date, Country of manufacturing, Check-Sum
7.2.6 Status register
1.	Register type:	PCF8574, Philips, or equivalent.
2.	Register content:	DC Fail, Over-Temperature Protection (OTP)
		Temperature Alarm, Fan Fail, AC Fail

CAUTION

The I2C bus address lines, serial clock and data are referenced to the -Sense potential. When using series connection of FPS1000 units, do not connect the I2C lines of the units together.

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