MC34717EP Freescale Semiconductor, MC34717EP Datasheet - Page 14

• Manufacturer Part Number: MC34717EP
• Description: IC CONVERTER DDR 26QFN
• Manufacturer: Freescale Semiconductor

Specifications of MC34717EP

• Applications: Converter, DDR
• Voltage - Input: 3 ~ 6 V
• Number Of Outputs: 2
• Voltage - Output: 0.7 ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 26-QFN
• Output Voltage: 0.7 V to 3.6 V
• Output Current: 5 A
• Input Voltage: 3 V to 6 V
• Switching Frequency: 1 MHz
• Operating Temperature Range: - 40 C to + 85 C
• Mounting Style: SMD/SMT
• No. Of Outputs: 2
• Power Dissipation Pd: 2.03W
• No. Of Pins: 26
• Filter Terminals: SMD
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

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
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 converters
switching frequency. The switching frequency can be
14
34717
FUNCTIONAL DESCRIPTION
FUNCTIONAL INTERNAL BLOCK DESCRIPTION
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
This block generates the clock cycles necessary to run the
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/
MC34717 - Functional Block Diagram
Internal Bias Circuits
Protection Functions
FUNCTIONAL INTERNAL BLOCK DESCRIPTION
Figure 4. Block Illustration
System Control and Logic
Supervisory Functions
2 x Buck Converter
Control and
programmed by connecting a resistor divider to the FREQ
pin, between VDDI and GND pins (See
PROTECTION FUNCTIONS
CONTROL AND SUPERVISORY FUNCTIONS
contains the following circuits.
This block contains the following circuits:
• Over-current limit and short-circuit detection: This block
• Thermal limit detection: This block monitors the
• Output over-voltage and under-voltage monitoring: This
This block is used to interface with an outside host. It
• Shutdown control input: An outside host can put the
• Power good output signal: The 34717 can communicate
monitors the output of the buck converters 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
threshold, this block will alert the system control for
further commands.
block monitors the buck converters output voltages to
ensure they are within regulation boundaries. If not, this
block alerts the system control for further commands.
34717 device into shutdown mode by sending a logic
“0” to the SD pin.
to an outside host that a fault has occurred by pulling
the voltage on the PG pin high.
Tracking and Sequencing
Oscillator
Analog Integrated Circuit Device Data
Freescale Semiconductor
Figure
1).