19-5273; Rev 0; 7/10
MAX9934T Evaluation Kit
General Description
The MAX9934T evaluation kit (EV kit) demonstrates
the MAX9934T low-voltage, precision, current-sense
amplifier for power management in portable consumer
electronics. The device’s precision inputs and the EV
kit’s on-board, precision, low-value sense resistor allows
the measurement of bidirectional (e.g., battery charge/
discharge) currents up to 1A. Input common-mode
range is -0.1V to +5.5V independent of supply. The
device demonstrates a 25FA/mV fixed gain and the
EV kit is configured for a 250V/V gain. The device’s
chip-select (CS) logic input allows users to multiplex
several MAX9934T parts. The EV kit operates from a
+2.5V to +3.6V, 100mA DC power supply.
The EV kit can also be used to evaluate the MAX9934F
current-sense amplifier. See the
Evaluating the MAX9934F
section for more information.
Sensing_Up_to_1A
S
EV_Kit_Configured_for_250V/V_Gain
S
Chip-Select_(CS)_Logic_Input
S
-0.1V_to_+5.5V_Input_Common-Mode_Range
S
+2.5V_to_+3.6V_DC_Power-Supply_Operation
S
Proven_PCB_Layout
S
Fully_Assembled_and_Tested
Features
S
EV_Kit_Configured_for_Bidirectional_Current_
Evaluates: MAX9934
Ordering Information
PART
MAX9934TEVKIT+
TYPE
EV Kit
+Denotes
lead(Pb)-free and RoHS compliant.
Selector Guide
PART
MAX9934T
MAX9934F
GAIN
25FA/mV
5FA/mV
OUTPUT
Current
Current
LOGIC_PIN
Chip-select input
Chip-select input
Component List
DESIGNATION
C1
QTY
1
DESCRIPTION
4.7FF
Q10%,
16V X7R ceramic
capacitor (0805)
Murata GRM219R71C475K
0.1FF
Q10%,
16V X7R ceramic
capacitors (0603)
Murata GRM188R71C104K
0.01FF
Q10%,
16V X7R ceramic
capacitor (0603)
Murata GRM188R71C103K
Not installed, ceramic capacitor
(0603)
Black miniature PCB test points
Black multipurpose PCB test
points
2-pin headers
Red multipurpose PCB test point
—
—
3
1
U2
1
DESIGNATION
R1
QTY
1
DESCRIPTION
10mI
Q0.1%, Q15ppm/°C
4-terminal resistor (2512)
Vishay Y14870R01000B9
10kI
Q0.1%, Q25ppm/°C
resistor (0603)
Panasonic ERA-3YEB103V
10kI
Q5%
resistors (0603)
White miniature PCB test points
Current-sense amplifier
(6 UCSPK)
Maxim MAX9934TART+
(Top Mark: AAF)
Current-sense amplifier
(8
FMAX
M
)
Maxim MAX9934TAUA+
Shunts (JU1, JU2, JU3)
PCB: MAX9934T EVALUATION
KIT+
C2, C4, C5
3
R2
R3, R4
RS+, RS-
1
2
2
C3
C6
GND
GND,
OUT_REF
JU1, JU2, JU3
OUT
1
0
2
2
3
1
U1
1
UCSP is a trademark and µMAX is a registered trademark of
Maxim Integrated Products, Inc.
________________________________________________________________ _Maxim
Integrated Products_
_ 1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
MAX9934T Evaluation Kit
Evaluates: MAX9934
Component Suppliers
SUPPLIER
Murata Electronics North America, Inc.
Panasonic Corp.
PHONE
770-436-1300
800-344-2112
WEBSITE
www.murata-northamerica.com
www.panasonic.com
Vishay
402-563-6866
www.vishay.com
Note:
Indicate that you are using the MAX9934_ when contacting these component suppliers.
Quick Start
U
U
U
U
U
MAX9934T EV kit
9)
Required Equipment
Connect the DVM positive terminal to the OUT PCB
pad and the negative terminal to the OUT_REF PCB
pad.
+2.5V to +3.6V, 100mA DC power supply for VCC
+5.5V, 2A DC power supply
2A electronic load
One digital voltmeter (DVM) with 10M
I
input imped-
ance
10) Enable the power supplies and the electronic load.
Any power sequence can be used without damage
to U1 or U2.
11) Verify that the DVM measures +2.5V.
Detailed Description of Hardware
The MAX9934T EV kit demonstrates the MAX9934T low-
voltage, precision, current-sense amplifier in a tiny 1mm
x 1.5mm, 3 x 2-bump UCSP package (U1) and an 8-pin
FMAX
package (U2). The EV kit can also be used to
evaluate the MAX9934F current-sense amplifier. Contact
the factory to obtain free samples. See the
Evaluating the
MAX9934F
section for more information.
The device’s precision inputs measure very small
sense voltages up to
Q10mV
full scale. The EV kit
features a precision, on-board, four-terminal surface-
mount sense resistor, R1 (10mI
Q0.1%, Q15ppm/NC).
This enables measurement of bidirectional currents up to
1A connected across the EV kit’s I_RS+ and I_RS- PCB
pads. The input common-mode range is -0.1V to +5.5V
independent of VCC. The EV kit operates from a +2.5V
to +3.6V, 100mA DC power supply connected across the
VCC and GND PCB pads.
The device’s 25FA/mV fixed-gain output current cre-
ates an output voltage across the output-load resistor,
R2 (10kI
Q0.1%),
achieving a 250V/V gain. R2 can be
replaced with an appropriate surface-mount 0603 resis-
tor to achieve different output gains. The EV kit’s output
voltage can be measured across the OUT and OUT_REF
PCB pads. Connect a 1.65V reference voltage across
the OUT_REF and GND PCB pads. The device’s CS pin
allows users to multiplex several MAX9934T parts.
Surface-mount 0603 capacitors C5 (installed) and C6
(not installed) provide optional input filters.
The EV kit is fully assembled and tested. Follow the steps
below to verify board operation:
1)
Procedure
Verify that jumpers JU1, JU2, and JU3 shunts are
in-stalled as follows:
JU1: Installed (OUT_REF PCB pad connected to
GND PCB pad)
JU2: Not installed (U1 output enabled)
JU3: Installed (U2 output disabled; high impedance)
2)
3)
4)
5)
Set the +2.5V to +3.6V, 100mA DC power-supply
voltage to +3.3V and disable the output.
Set the +5.5V, 2A DC power-supply voltage to +5V,
the current limit above 1A, and disable the output.
Set the electronic load to 1A and disable the output.
Connect the low-power DC power-supply positive
terminal to the VCC PCB pad and the negative ter-
minal to the nearby GND PCB pad.
Connect the 2A DC power-supply positive terminal
to the I_RS+ PCB pad and the negative terminal to
the GND PCB pad.
Connect the 2A electronic load positive terminal to
the I_RS- PCB pad and the negative terminal to the
GND PCB pad.
Set the DVM to measure voltage.
6)
7)
8)
2_ _ _______________________________________________________________________________________
MAX9934T Evaluation Kit
Evaluates: MAX9934
Jumpers JU2 and JU3 enable or disable the respective
amplifier’s output by controlling the device’s CS pins
on U1 and U2, respectively. An external controller can
drive the U1 and U2 CS input pins using the EV kit’s
CS1(SIGN1) and CS2(SIGN2) PCB pads, respectively.
The CS pins are compatible with +1.8V through +3.3V
logic. Connect the external controller’s logic ground
return to a GND PCB pad and remove pullup resistors R3
and R4, if not needed. See Tables 1 and 2 for jumpers
JU2 and JU3 configuration.
Chip Select (CS)
To evaluate the MAX9934F, replace U1 (3 x 2-bump
UCSP) or U2 (8-pin
FMAX)
with the appropriate version.
The device can be multiplexed with other MAX9934F
parts. See the
Chip Select (CS)
section for additional
information.
Output Measurements
The device provides a current output that can be
measured across the OUT and OUT_REF PCB pads.
Connect a 1.65V reference voltage across the OUT_REF
and GND PCB pads.
Evaluating the MAX9934F
Table_1._U1_CS_Pin_Logic_Input_(JU2)
SHUNT_
POSITION
Not
installed
Installed
U1_CS_PIN_
CONNECTION
Pulled up to VCC
through R3
GND
EV_KIT_FUNCTION
U1 output enabled
U1 output disabled
(high impedance)
Table_2._U2_CS_Pin_Logic_Input_(JU3)
SHUNT_
POSITION
Not
installed
Installed
U2_CS_PIN_
CONNECTION
Pulled up to VCC
through R4
GND
EV_KIT_FUNCTION
U2 output enabled
U2 output disabled
(high impedance)
________________________________________________________________________________________ _ 3
Evaluates: MAX9934
VCC
OUT
VCC
R2
C1
4.7uF
GND
C2
1
JU1
2
0.1uF
A1
A2
A3
GND
GND
10k
0.1%
C3
0.01uF
OUT_REF
OUT_REF
OUT
MAX9934T Evaluation Kit
Figure 1. MAX9934T EV Kit Schematic
OUT
VCC
U1
MAX9934TART+
OUT
GND
VCC
VCC
1
RS+
VCC
8
RS+
RS+
B1
B2
B3
C4
0.1uF
RS-
CS
R3
10k
CS1(SIGN1)
RS-
U2
OUT
RS+
RS+
CS
2
RS-
OUT
7
1
RS-
RS-
E1
I1
0.1%
10m
R1
E2
I2
OPEN
C6
GND
MAX9934TAUA+
C5
GND
0.1uF
N.C.
JU2
2
GND
3
6
GND
4
5
N.C.
VCC
R4
10k
I_RS+
1
JU3
2
I_RS-
4_ _ _______________________________________________________________________________________
CS2(SIGN2)
MAX9934T Evaluation Kit
Evaluates: MAX9934
1.0’’
Figure 2. MAX9934T EV Kit Component Placement Guide—
Component Side
1.0’’
Figure 3. MAX9934T EV Kit PCB Layout—Component Side
1.0’’
Figure 4. MAX9934T EV Kit PCB Layout—Solder Side
________________________________________________________________________________________ _ 5
国产芯片交流
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
