MAX9643TASA+ Maxim Integrated, MAX9643TASA+ Datasheet - Page 9

• Manufacturer Part Number: MAX9643TASA+
• Description: Current Sense Amplifiers 60V High-Speed Prec current-Sense Amp
• Manufacturer: Maxim Integrated
• Series: MAX9643r

Specifications of MAX9643TASA+

• Rohs: yes

input voltage transients below -3.5V should be limited by
the use of input series resistors. For example, if an input
voltage transient or fault condition of -12V were to occur
in the application, use a resistor greater than 8.5V/5mA =
1700I. Use 2kI for margin.
The maximum input common-mode voltage extends up
to 60V over the entire V
ommended to shield the device from overvoltages above
its 65V absolute maximum rating to protect the device.
The internal negative voltage rail generated by the
charge pump is also used to bias the output stage of
the current-sense amplifier, allowing it to feature true
V
voltages to be used and eases interface to other analog
and mixed-signal ICs. In reality, attaining true V
specification is usually limited by the offset voltage of the
current-sense amplifier since V
input V
In addition, the maximum output voltage of the IC is inter-
nally clamped to less than 5V even when it is powered
from a 40V rail. This allows easy interface to low-voltage
downstream circuitry without worrying about protecting
them from large input voltage transients or faults.
When the AC common-mode signal with large ampli-
tudes (>5V
(> 1kHz for example) is present at the inputs, AC
CMRR limitation causes spikes at the output as shown
in the Common Mode graph in the Typical Operating
Characteristics. Application Note 3888: Performance
of Current-Sense Amplifiers with Input Series Resistors
explains the way to filter out these common-mode tran-
sients as seen by the amplifier and filtering of the differ-
ential mode.
PROCESS: BiCMOS
Maxim Integrated
OL
60V High-Speed Precision Current-Sense Amplifier
= 0V performance. This feature allows small sense
Common Mode and Differential Filtering
SENSE
P-P
= 0V.
for example) at high frequencies
CC
range of 2.7V to 36V. It is rec-
Output Voltage Range
Chip Information
OUT
= V
OS
x gain, when
OL
= 0V
Choose R
U Voltage loss: A high R
U Accuracy: A high R
U Efficiency and power dissipation: At high current
U Inductance: Keep inductance low if I
For most applications, bypass V
ceramic capacitor. In many applications, V
connected to one of the current monitor terminals (R
or R
voltage, V
supply. There are no specific power-supply sequencing
issues to consider. The part can withstand 60V input
common-mode voltages even when V
maintains a high input impedance in this application
condition.
+Denotes a lead(Pb)-free/RoHS-compliant package.
*EP = Exposed pad.
MAX9643TATA+
MAX9643UATA+
power-source voltage to reduce due to IR drop. For
minimal voltage loss, use the lowest R
to be measured more accurately. This is because
input offset voltages become less significant when the
sense voltage is larger.
levels, the I
Take this into consideration when choosing the resis-
tor value and its power dissipation (wattage) rating.
Also, the sense resistor’s value might drift if it is
allowed to heat up excessively.
large high-frequency component. Because of the
high currents that flow through R
to eliminate parasitic trace resistance from causing
errors in the sense voltage. Either use a four-terminal
current-sense resistor or use Kelvin (force and sense)
PCB layout techniques.
S-
Power-Supply Bypassing and Grounding
). Because V
PART
SENSE
CC
can be connected to a separate regulated
2
R losses in R
based on the following criteria:
PIN-
PACKAGE
8 TDFN-EP*
8 TDFN-EP*
Choosing the Sense Resistor
CC
SENSE
Ordering Information
is independent of the monitored
value allows lower currents
SENSE
SENSE
CC
GAIN
(V/V)
2.5
10
MAX9643
to GND with a 0.1FF
can be significant.
value causes the
SENSE
-40NC to +125NC
-40NC to +125NC
CC
SENSE
SENSE
RANGE
, take care
CC
= 0V, and
TEMP
value.
can be
has a
S+
9