MAX9939EVKIT+ Maxim Integrated Products, MAX9939EVKIT+ Datasheet - Page 7

• Manufacturer Part Number: MAX9939EVKIT+
• Description: KIT EVAL FOR MAX9939
• Manufacturer: Maxim Integrated Products

Specifications of MAX9939EVKIT+

• Channels Per Ic: 2 - Dual
• Amplifier Type: Programmable Gain
• Output Type: Differential
• Slew Rate: 9 V/µs
• Current - Output / Channel: 70mA
• Operating Temperature: -40°C ~ 125°C
• Current - Supply (main Ic): 3.4mA
• Voltage - Supply, Single/dual (±): 2.9 V ~ 5.5 V
• Board Type: Fully Populated
• Utilized Ic / Part: MAX9939
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• -3db Bandwidth: -

The MAX9939 is a general-purpose PGA with input off-
set trim capability. Its gain and input offset voltage
(V
an uncommitted output operational amplifier that can
be used as either a high-order active filter or to provide
a differential output. The device can be put into shut-
down through SPI.
The gain of the amplifier is programmable between
0.2V/V and 157V/V. The input offset is programmable
between ±17mV and can be used to regain output
dynamic range in high gain settings. An input offset-volt-
age measurement mode enables input offset voltage to
(V
CC
OS
PIN
10
1
2
3
4
5
6
7
8
9
) are SPI programmable. The device also includes
= 5V, V
NAME
OUTB
OUTA
SCLK
INA+
GND
INA-
V
GND
DIN
INB
CS
CC
= 0V, V
Serial-Clock Input
Serial-Data Input. Data is clocked into the serial interface on the rising edge of SCLK.
Ground
PGA Inverting Input
PGA Noninverting Input
Buffer Output
Buffer Input
PGA Output
Power Supply. Bypass to GND with 0.1µF and 1µF capacitors.
Acti ve- Low C hi p - S el ect Inp ut. D r i ve CS l ow to enab l e the ser i al i nter face. D r i ve CS hi g h to d i sab l e the ser i al i nter face.
_______________________________________________________________________________________
COMMON-MODE REJECTION RESPONSE
with Input V
IN+
Detailed Description
= V
IN-
200µs/div
= 0V, Gain = 10V/V, R
V
V
CM
DM
SPI Programmable-Gain Amplifier
= 1V
= 25mV
GAIN = 157V/V
P-P
, 1kHz
P-P
MAX9939 toc19
, 10kHz
Typical Operating Characteristics (continued)
OUTA
2V/div
INA+
1V/div
INA-
1V/div
OS
OUTA
= R
Trim and Output Op Amp
OUTB
be calibrated out in firmware to obtain excellent DC
accuracy.
The main amplifier accepts a differential input and pro-
vides a single-ended output. The relationship between
the differential input and singled-ended output is given
by the representative equation:
The MAX9939 features three internal amplifiers as
shown in the Functional Diagram . The first amplifier
(amplifier LVL) is configured as a differential amplifier
for differential to single-ended conversion with an input
offset-voltage trim network. It has extremely high
V
FUNCTION
OUTA
= 1kΩ to V
= V
20
16
12
8
4
0
SHUTDOWN CURRENT vs. SUPPLY VOLTAGE
CC
2.8
CC
/2 + Gain x (V
/2, T
3.2
A
= +25°C, unless otherwise noted.)
3.6
VOLTAGE (V)
4.0
INA+
4.4
Pin Description
4.8
- V
INA-
5.2
Architecture
) + Gain x V
OS
7