AS8500 - Data Sheet

austriamicrosystems

Revision 1.2, 08-Junel-06

www.austriamicrosystems.com

Page 7 of 41

Electrical characteristics (continued)

VDDA=5V +/-0.1 V, fclk=8.192 MHz, chopping ratio MM=4 (see 7.5.3), oversampling frequency=2.048 MHz, oversampling ratio =128

temperature range : -40 to 125°C if not otherwise noted

symbol

parameter

conditions

min

typ

max

units

data conversion

RES

resolution

all channels

16

bits

1) 2)

Vref

reference voltage

room temperature

1.21

V

Vref_TC

temperature coefficient of Vref

0-85°C,box

method

20

ppm/K

3)

Vref_Ri

internal resistance of Vref

Rload > 50 kOhm

200

Ohm

fovs

clock frequency

4.096

MHz

R1

oversamplig ratio

64

128

MM

conversions during chopper cycle

4

8

BW

bandwidth

7.8

1000

16000

Hz

av

internal averaging

1

4

1024

cycles

fclk

external clock frequency

0.05

8.192

10

MHz

4)

CLK_extdiv

clock division factor

2

4

DR_clk

duty ratio of external clock

50

%

int_fclk

internal clock frequency

180

250

330

kHz

analog inputs

RSHH, VBAT, ETS, ETS

Rin

input resistance

Ue < 150 mV

50

100

MOhm

Cin

input capacitance at gain 24

8

15

30

pF

internal temperature sensor

T_out20

output at 23°C

G 6, typical

23 000

digits

T_sl

slope

-20 to 100°C

75

digits/degC

current source

output to RSHH, RSHL

Icurr_rshh

2

µA

Notes:

1)

with external averaging the resolution can be increased up to 21 bits with an effective sampling rate below 10 Hz

2

) the system works in overflow condition without degradation of accuracy up to 1.4 * range width.

This means that the overflow bit can work as bit no.17 in this range.

3)

TC- value of the reference voltage may be set through trimm bits intentionally higher to minimize TC of the entire measurement path for gain 24

4)

in the temperature range 0 - 85°C the clock frequency can be increased to 12 MHz