MCZ34702EWR2 Freescale Semiconductor, MCZ34702EWR2 Datasheet - Page 22

• 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

THERMAL SHUTDOWN
the 34702, an internal thermal shutdown function has been
incorporated into the switching regulator circuit. The 34702
senses the temperature of the buck regulator main switching
MOSFET (high side MOSFET M1; see
the low side (synchronous MOSFET M2), and control circuit.
If the temperature of any of the monitored components
exceeds the limit of safe operation (thermal shutdown), the
switching regulator and the LDO shut down. After the
temperature falls below the value given by the thermal
shutdown hysteresis window, the switcher tries again to
operate.
thermal shutdown control. If the M3 temperature exceeds the
thermal shutdown limit, the M3 is turned off without affecting
the switcher operation.
thermal shutdown control. If the M4 temperature exceeds the
thermal shutdown limit, the M4 will be turned off without
affecting the LDO operation.
SOFT START
the 34702. The soft start is active each time the IC is enabled,
VIN is reapplied, or after a fault retry. Other transient events
do not activate the soft start.
VOLTAGE MARGINING
through the I
independent adjustment of the Switcher V
the linear output V
in 1.0% steps to a range of ±7.0%. This feature allows for
worst case system validation; i.e., determining the design
margin. Margining details are described in the section entitled
I
22
34702
FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
2
C Bus Operation, beginning on page
To increase the overall safety of the system designed with
The V
The LDO pull-down MOSFET M4 has an independent
A switching regulator soft start feature is incorporated in
The 34702 includes a voltage margining feature accessed
OUT
2
C bus. Voltage margining allows for
pull-down MOSFET M3 has an independent
LDO
. Each can be adjusted up and down
FUNCTIONAL DEVICE OPERATION
26
Figure 2
OUT
of this datasheet.
voltage and
on page 2),
OPERATIONAL MODES
POWER SEQUENCING MODES
supply IC is in compliance with the Freescale Power QUICC
and other 32-bit microprocessor requirements. When the
input voltage is applied, the switcher and linear regulator
outputs follow the supply rail voltage during power-up and
power-down in the limits given by the microcontroller power
sequencing specification, illustrated in
19. There are two possible power sequencing modes,
Standard and Inverted, as explained in more detail below.
The third mode of operation is Power Sequencing Disabled.
Slope
Optional
1.0 V/ms
(typ.)
1.8V Start-Up
The power sequencing of the two outputs of this power
Figure 17. Standard Power-up / Down Sequence
3.3 V Input Supply (I/O Voltage)
ADDR
GND
VIN2
VBD
RT
SDA
SCL
CLKSYN
CLKSEL
FREQ
VBST
EN1
EN2
1.5 V Core Voltage
∆V = 2.1 V
Max. Lead
in +3.3V Supply System
34702
3.3 V Input
BOOT
PGND
Analog Integrated Circuit Device Data
VOUT
LDRV
VDDI
VIN1
LDO
RST
LFB
INV
SW
CS
∆V = 0.4 V
Max. Lag
Freescale Semiconductor
VBST
Figures 17
2.5 V
3.3 V
1.5 V
VDDL (Core)
VDDH (I/Os)
Circuits
∆V = 2.1 V
Max. Lead
Other
through
MCU