MC34713EP Freescale, MC34713EP Datasheet - Page 11

• Manufacturer Part Number: MC34713EP
• Manufacturer: Freescale

Specifications of MC34713EP

• Operating Temperature (max): 85C
• Operating Temperature (min): -40C
• Pin Count: 24
• Mounting: Surface Mount
• Package Type: QFN
• Case Length: 4mm
• Screening Level: Industrial
• Lead Free Status / RoHS Status: Compliant

enhance the gate of the high side Power MOSFET during
switching.
SHUTDOWN INPUT (SD)
Shutdown mode. If left unconnected or tied to the VIN pin, the
device will be in Normal mode. The pin has an internal pull-
up of 1.5 MΩ.
INTERNAL BIAS CIRCUITS
supply voltages and bias currents for the internal circuitry. It
consists of:
SYSTEM CONTROL AND LOGIC
processes data and reacts to it. Based on the status of the SD
pin, the system control reacts accordingly and orders the
device into the right status. It also takes inputs from all of the
monitoring/protection circuits and initiates power up or power
Analog Integrated Circuit Device Data
Freescale Semiconductor
If this pin is tied to the GND pin, the device will be in
This block contains all circuits that provide the necessary
• Internal voltage supply regulator: This regulator
• Internal bandgap reference voltage: This supplies the
• Bias circuit: This block generates the bias currents
This block is the brain of the IC where the device
supplies the V
analog internal circuits. It is equipped with a Power-On-
Reset (POR) circuit that watches for the right regulation
levels. External filtering is needed on the VDDI pin. This
block will turn off during the shutdown mode.
reference voltage to some of the internal circuitry.
necessary to run all of the blocks in the IC.
DDI
voltage that is used to drive the digital/
MC34713 - Functional Block Diagram
Internal Bias Circuits
Protection Functions
FUNCTIONAL INTERNAL BLOCK DESCRIPTION
Figure 4. 34713 Block Diagram
System Control and Logic
Supervisory Functions
Buck Converter
Control and
POWER GOOD OUTPUT SIGNAL (PG)
report the status of the device to a host. This output activates
after a successful power up sequence and stays active as
long as the device is in normal operation and is not
experiencing any faults. This output activates after a 10 ms
delay and must be pulled up by an external resistor to a
supply voltage (e.g., V
down commands. It communicates with the buck converter to
manage the switching operation and protects it against any
faults.
OSCILLATOR
IC digital blocks. It also generates the buck converter
switching frequency. The switching frequency has a default
value of 1.0 MHz and can be programmed by connecting a
resistor divider to the FREQ pin, between VDDI and GND
pins (See
PROTECTION FUNCTIONS
This is an active low open drain output that is used to
This block generates the clock cycles necessary to run the
This block contains the following circuits:
• Over-current limit and short-circuit detection: This block
• Thermal limit detection: This block monitors the
monitors the output of the buck converter for over
current conditions and short-circuit events and alerts
the system control for further command.
temperature of the device for overheating events. If the
temperature rises above the thermal shutdown
Figure
Tracking and Sequencing
FUNCTIONAL INTERNAL BLOCK DESCRIPTION
1).
Oscillator
IN
).
FUNCTIONAL DESCRIPTION
34713
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