PGA309

SBOS292A − DECEMBER 2003 − REVISED AUGUST 2004

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3

ELECTRICAL CHARACTERISTICS

TA = +25°C, VSA = VSD = +5V (VSA = VSUPPLY ANALOG, VSD = VSUPPLY DIGITAL; VSA must equal VSD), GNDD = GNDA = 0, and VREF = REFIN/REFOUT = +5V,

unless otherwise noted.

PGA309

PARAMETER

CONDITIONS

MIN

TYP

MAX

UNITS

FRONT-END PGA + OUTPUT AMPLIFIER

VOUT/VIN Differential Signal Gain Range(1)

Fine Gain Adjust = 1

Front-End PGA Gains: 4, 8, 16, 23.27, 32, 42.67, 64, 128

Output Amplifier Gains: 2, 2.4, 3, 3.6, 4.5, 6, 9

8 to 1152

V/V

VOUT Slew Rate

0.5

V/

µs

VOUT Settling Time (0.01%)

VOUT/VIN Differential Gain = 8, RL = 5kΩ || 200pF

6

µs

VOUT Settling Time (0.01%)

VOUT/VIN Differential Gain = 191, RL = 5kΩ || 200pF

4.1

µs

VOUT Nonlinearity

0.002

%FSR

External Sensor Output Sensitivity

VSA = VSD = VEXC = +5V

1 to 245

mV/V

FRONT-END PGA

Auto-Zero Internal Frequency

7

kHz

Offset Voltage (RTI)(2)

Coarse Offset Adjust Disabled

±3

±50

µV

vs Temperature

+0.2

µV/°C

vs Supply Voltage, VSA

±2

µV/V

vs Common-Mode Voltage

GF = Front-End PGA Gain

1500/GF

6000/GF

µV/V

Linear Input Voltage Range(3)

0.2

VSA−1.5

V

Input Bias Current

0.1

1.5

nA

Input Impedance: Differential

30 || 6

G

Ω || pF

Input Impedance: Common-Mode

50 || 20

G

Ω || pF

Input Voltage Noise

0.1Hz to 10Hz, GF = 128

4

µVPP

PGA Gain

Gain Range Steps

4, 8, 16, 23.27, 32, 42.67, 64, 128

4 to 128

V/V

Initial Gain Error

GF = 4 to 42

0.2

±1

%

GF = 64

0.25

±1.2

%

GF = 128

0.3

±1.6

%

vs Temperature

10

ppm/

°C

Output Voltage Range

0.05 to VSA − 0.1

V

Bandwidth

Gain = 4

400

kHz

Gain = 128

60

kHz

COARSE OFFSET ADJUST

(RTI OF FRONT-END PGA)

Range

±(14)(VREF)(0.00085)

±56

±59.5

±64

mV

vs Temperature

0.004

%/

°C

Resolution

±14 steps, 4-Bit + Sign

4

mV

FINE OFFSET ADJUST (ZERO DAC)

(RTO of the Front-End PGA)(2)

Programming Range

0

VREF

V

Output Range

0.1

VSA−0.1

V

Resolution

65,536 steps, 16-Bit DAC

73

µV

Integral Nonlinearity

20

LSB

Differential Nonlinearity

0.5

LSB

Gain Error

0.1

%

Gain Error Drift

10

ppm/

°C

Offset

5

mV

Offset Drift

10

µV/°C

OUTPUT FINE GAIN ADJUST (GAIN DAC)

Range

0.33 to 1

V/V

Resolution

65,536 steps, 16-Bit DAC

10

µV/V

Integral NonLinearity

20

LSB

Differential NonLinearity

0.5

LSB