TLC1514, TLC1518

5-V, 10-BIT, 400 KSPS, 4/8 CHANNEL, LOW POWER,

SERIAL ANALOG-TO-DIGITAL CONVERTERS WITH AUTO POWER DOWN

SLAS252 – DECEMBER 1999

32

POST OFFICE BOX 655303

• DALLAS, TEXAS 75265

PRINCIPLES OF OPERATION

1000000000

0111111111

0000000010

0000000001

0000000000

1111111110

0

0.00976

2.4937

2.4986

2.5034

1000000001

1111111101

1111111111

4.9874

4.9922

4.9871

512

511

2

1

0

1022

513

1021

1023

VI – Analog Input Voltage – V

VZT =VZS + 1/2 LSB

VZS

See Notes A and B

0.00488

VFT = VFS – 1/2 LSB

VFS

VFS Nom

NOTES: A. This curve is based on the assumption that Vref+ and Vref– have been adjusted so that the voltage at the transition from digital 0 to

1 (VZT) is 2.44 mV, and the transition to full scale (VFT) is 4.9898 V, 1 LSB = 4.88 mV.

B. The full scale value (VFS) is the step whose nominal midstep value has the highest absolute value. The zero-scale value (VZS) is

the step whose nominal midstep value equals zero.

Figure 36. Ideal 10-Bit ADC Conversion Characteristics

GND

CS

XF

TMS320 DSP

TLC1514/

TLC1518

SDI

SDO

SCLK

INT

TXD

RXD

CLKR

BIO

10 k

Ω

vcc

AIN

VDD

FSR

FS

CLKX

FSX

Figure 37. Typical Interface to a TMS320 DSP