Datasheet

LTC2481

2481fc

APPLICATIONS INFORMATION

LTC248X.h

Processor setup and

Lots of useful deﬁ nes for conﬁ guring the LTC2481 and LTC2485.

#include <16F73.h> // Device

#use delay(clock=6000000) // 6MHz clock

//#fuses NOWDT,HS, PUT, NOPROTECT, NOBROWNOUT // Conﬁ guration fuses

#rom 0x2007={0x3F3A} // Equivalent and more reliable fuse conﬁ g.

#use I2C(master, sda=PIN_C5, scl=PIN_C3, SLOW)// Set up i2c port

#include “PCM73A.h” // Various deﬁ nes

#include “lcd.c” // LCD driver functions

// Useful deﬁ nes for the LTC2481 and LTC2485 - OR them together to make the

// 8 bit conﬁ g word.

#deﬁ ne READ 0x01 // bitwise OR with address for read or write

#deﬁ ne WRITE 0x00

#deﬁ ne LTC248XADDR 0b01001000 // The one and only LTC248X in this circuit,

// with both address lines ﬂ oating.

// Select gain - 1 to 256 (also depends on speed setting)

#deﬁ ne GAIN1 0b00000000 // G = 1 (SPD = 0), G = 1 (SPD = 1)

#deﬁ ne GAIN2 0b00100000 // G = 4 (SPD = 0), G = 2 (SPD = 1)

#deﬁ ne GAIN3 0b01000000 // G = 8 (SPD = 0), G = 4 (SPD = 1)

#deﬁ ne GAIN4 0b01100000 // G = 16 (SPD = 0), G = 8 (SPD = 1)

#deﬁ ne GAIN5 0b10000000 // G = 32 (SPD = 0), G = 16 (SPD = 1)

#deﬁ ne GAIN6 0b10100000 // G = 64 (SPD = 0), G = 32 (SPD = 1)

#deﬁ ne GAIN7 0b11000000 // G = 128 (SPD = 0), G = 64 (SPD = 1)

#deﬁ ne GAIN8 0b11100000 // G = 256 (SPD = 0), G = 128 (SPD = 1)

// Select ADC source - differential input or PTAT circuit

#deﬁ ne VIN 0b00000000

#deﬁ ne PTAT 0b00001000

// Select rejection frequency - 50, 55, or 60Hz

#deﬁ ne R50 0b00000010

#deﬁ ne R55 0b00000000

#deﬁ ne R60 0b00000100

// Speed settings is bit 7 in the 2nd byte

#deﬁ ne SLOW 0b00000000 // slow output rate with autozero

#deﬁ ne FAST 0b00000001 // fast output rate with no autozero