MCZ34702EWR2 Freescale Semiconductor, MCZ34702EWR2 Datasheet - Page 25

• Manufacturer Part Number: MCZ34702EWR2
• Description: IC PWR SUPPLY 3A SW 32-SOIC
• Manufacturer: Freescale Semiconductor

Specifications of MCZ34702EWR2

• Applications: Controller, Power QUICC™ I, II
• Voltage - Input: 2.8 ~ 6 V
• Number Of Outputs: 2
• Voltage - Output: 7.75V, 0.8 ~ 6 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 32-SOIC (7.5mm Width)
• Output Current: 3 A
• Input Voltage: 2.8 V to 6 V
• Switching Frequency: 300 KHz
• Mounting Style: SMD/SMT
• Duty Cycle (max): 95 %
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Single 5.0V Supply, VIN1 = VIN2, or Dual Supply VIN1 ≠
VIN2
switcher supplies the core (e.g., 1.5V nominal) (see
Figure
Power-up
load current and capacitance, and the relative rise times of
the VIN1 and VIN2 supplies. There are two cases:
Power-down
and capacitance, and the relative fall times of the VIN1 and
VIN2 supplies. There are two cases:
Shorted Load
INVERTED OPERATING MODE
Single 3.3V Supply, VIN = VIN1 = VIN2 = 3.3V
LDO supplies core voltage (e.g., 1.5V nominal), and the
switcher VOUT operates independently. Power sequencing
Analog Integrated Circuit Device Data
Freescale Semiconductor
1. LDO rises faster than VOUT . The LDO uses control
2. VOUT rises faster than LDO. The switcher uses control
1. VOUT falls faster than LDO. The LDO uses control
2. LDO falls faster than VOUT . The switcher uses control
1. VOUT shorted to ground. The LDO uses method (1)
2. LDO shorted to ground. The switcher uses control
3. VIN1 shorted to ground. The device is not working.
4. VIN2 shorted to ground with VIN1 and VIN2 different.
5. VOUT shorted to supply. No load protection. 34702 is
6. LDO shorted to supply. No load protection. 34702 is
The LDO supplies the microprocessor I/O voltage. The
This condition depends upon the regulator current limit,
This condition depends upon the regulator load current
The 3.3V supplies the microprocessor I/O voltage, the
methods (1) and (2) described in the section
of Control on page
methods (5) and (6) described in the section
of Control on page
methods (1) and (2) described in the section
of Control on page
In the case VIN1 = VIN2, the intrinsic operation turns
on both the buck high side MOSFET and the LDO
external Pass MOSFET, and discharges the LDO load
capacitor into the VIN supply.
methods (5) and (6) described in the section
of Control on page
and (2) described in the section
page
methods (5) and (6) described in the section
of Control on page
This is equivalent to the switcher output shorted to
ground.
protected by current limit and thermal shutdown.
protected by current limit and thermal shutdown.
18, page 23).
23.
23.
23.
23.
23.
23.
Methods of Control on
Methods
Methods
Methods
Methods
Methods
depends only on the normal LDO intrinsic operation to control
the Pass MOSFET.
Power-up
point and the Pass MOSFET is on. In order not to exceed the
2.1V differential requirement between the I/O (VIN) and the
core (LDO), the LDO must start up at 2.1V or less and be able
to maintain the 2.1V or less differential. The maximum slew
rate for V
Power-down
therefore, the Pass MOSFET is on. In the case where LDO is
falling faster than VIN, the Pass MOSFET attempts to
maintain LDO. In the case where VIN is falling faster than
LDO, the Pass MOSFET is also on, and the LDO load
capacitor is discharged through the Pass MOSFET to VIN.
Thus, provided VIN does not fall too fast, the core voltage
(LDO) does not exceed the I/O voltage (VIN) by more than
maximum of 0.4V.
Shorted Load
Single 5.0V Supply, VIN1 = VIN2, or Dual Supply VIN1 ≠
VIN2
voltage. The LDO supplies the core (e.g., 1.5V nominal) (see
Figure
Power-up
load current and capacitance, and the relative rise times of
the VIN1 and VIN2 supplies. There are two cases:
Power-down
and capacitance and the relative fall times of the VIN1 and
VIN2 supplies. There are two cases:
1. LDO shorted to ground. This will cause the I/O voltage
2. VIN shorted to ground. Until the LDO load capacitance
3. LDO shorted to supply. No load protection.
1. VOUT rises faster than LDO. The switcher VOUT uses
2. LDO rises faster than VOUT . The LDO uses control
When VIN is rising, initially LDO is below the regulation
When VIN is falling, LDO falls below the regulation point;
The switcher VOUT supplies the microprocessor I/O
This condition depends upon the regulator current limit,
This condition depends upon the regulator load current
to exceed the core voltage by more than 2.1V. No load
protection.
is discharged, the core voltage exceeds the I/O voltage
by more than 0.4V. By the intrinsic operation of the
LDO, the load capacitor is discharged rapidly through
the Pass MOSFET to VIN.
control methods (1) and (2) described in the section
Methods of Control on page
methods (5) and (6) described in the section
of Control on page
19, page 23).
IN
is 1.0V/ms.
23.
FUNCTIONAL DEVICE OPERATION
23.
OPERATIONAL MODES
Methods
34702
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