MAX4211 Maxim, MAX4211 Datasheet - Page 23

• Manufacturer Part Number: MAX4211
• Description: The MAX4210/MAX4211 low-cost, low-power, high-side power/current monitors provide an analog output voltage proportional to the power consumed by a load by multiplying load current and source voltage
• Manufacturer: Maxim

Figure 1. Window Comparator for Detecting Underpower and Overpower Faults (Also Detects Undercurrent and Overcurrent Faults
by R1 and R4 to IOUT Instead of POUT)
Figure 3 shows single-ended input, variable-gain ampli-
fiers (VGA). This VGA features more than 200kHz band-
width and is useful in automatic gain-control circuits
commonly found in baseband processors. The gain is
controlled by applying 0 to 1V to IN (V
MAX4210D/E/F; 0V corresponds to minimum gain and
1V corresponds to maximum gain.
The MAX4210A/B/C and MAX4211A/B/C have internal
voltage-divider resistors connected to RS+ and the
analog multiplier input. This configuration measures
source power accurately and provides protection to the
power source such as a battery. To measure the load
4V TO
28V
______________________________________________________________________________________
UNDERPOWER
+
-
OVER/
Variable-Gain Amplifier
Measure Load Power
2.7V TO
V
PULLUP
5.5V
+
-
GC
V
INHIBIT
LE
COUT1
COUT2
CC
) of the
MAX4211C
MAX4211A
MAX4211B
25:1
+
RS+
power accurately, choose the MAX4210D/E/F and
MAX4211D/E/F with an external resistor-divider con-
nected directly to the load as shown in Figure 4. This
configuration improves the load-power measurement
accuracy by excluding the additional power dissipated
by R
Bypass V
isolate the IC from supply-voltage transients. To pre-
vent high-frequency coupling, bypass RS+ or RS- with
a 0.1µF capacitor. On the TDFN and thin QFN pack-
ages, there is an exposed paddle that does not carry
any current, but should also be connected to the
ground plane for rated power dissipation.
GND
REFERENCE
V
R
1.21V
SENSE
SENSE
SENSE
High-Side Power and
CC
RS-
.
CIN1+
CIN1-
CIN2+
-
CIN2-
POUT
IOUT
REF
to GND with a 0.1µF ceramic capacitor to
Current Monitors
Power-Supply Bypassing
R1
R2
LOAD
R4
R5
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