IR3725MPBF International Rectifier, IR3725MPBF Datasheet - Page 4

• Manufacturer Part Number: IR3725MPBF
• Description: Input Power Monitor IC with Digital Interface
• Manufacturer: International Rectifier

Specifications of IR3725MPBF

• Package: 12 Lead DFN
• Bias Supply Voltage: +3.3V +/-5%
• Junction Temperature: 0oC to 125oC
• Pbf: Yes

IC PIN FUNCTIONS
VDD PIN
This pin provides operational bias current to circuits
internal to the IR3725. Bypass it with a high quality
ceramic capacitor to the GND pin.
GND PIN
This pin returns operational bias current to its source.
It is also the reference to which the voltage VO is
measured, and it sinks the reference current
established by the external resistor R
VO PIN
This pin is to be electrically connected to the location
in the circuit where voltage for the power calculation
is desired to be monitored. Power accuracy may be
degraded if the voltage at this pin is below VO
VCS1 AND VCS2 PINS
The average current into these pins is used to
calculate power. Current sources internal to the
IR3725 will null the average voltage between this pin
pair.
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NAME
VCS1
VCS2
VO
VT
GND
VDD
EXTCLK
ADDR
SCL
SDA
ALERT#
NC
PIN DESCRIPTION
NUMBER
10
11
12
1
2
3
4
5
6
7
8
9
I/O LEVEL
Analog 12V
Analog 12V
Analog 12V
Analog
0V
3.3V
3.3V Digital
3.3V Digital
3.3V Digital
3.3V Digital
3.3V Digital
T
.
DESCRIPTION
Current sensing input 1
Current sensing input 2
Voltage sensing input
Thermistor sensing input
IC bias supply and signal ground
3.3V bias supply
Input for optional external clock
Bus Address selection input
Bus Clock; Input only
Bus Data; Input / Open drain output
Programmable output function; Open drain output clamped to VDD
Do not connect
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min
.
VT FUNCTION
A voltage internal to the IR3725 drives the VT pin
while the pin current is monitored and used to set the
amplitude of the switched current source IT. This pin
should be connected to GND through a precision
resistor network RT. This network may include
provision for canceling the positive temperature
coefficient of the inductor’s DC resistance (DCR).
ALERT# FUNCTION
The ALERT# pin is a multi-use pin. During normal
use it can be configured via the serial bus as an open
drain ALERT# pin that will be driven logic low when
new data is available in the output register. After the
output register has been read via the serial bus the
ALERT# will be released to its high resistance state.
This pin can also be programmed to pull low when
the output exceeds the programmable level.
IR3725
Data Sheet
2011_11_16