FUNCTIONAL DEVICE OPERATION
SUPPLIES
Table 43. Power Tree Summary
Supply
Purpose (Typical Application)
Output Voltage (in V)
2.5/2.6/2.75/3.0
Load Capability (in mA)
Camera supply, internal PMOS
65
VCAM
Camera supply, external PNP
2.5/2.6/2.75/3.0
250
200
350
50
VGEN1
VGEN2
General peripherals supply #1, external PNP
General peripherals supply #2, external PNP
General peripherals supply #3, internal PMOS
General peripherals supply #3, external PNP
USB Transceiver supply
1.2/1.5/2.775/3.15
1.2/1.5/1.6/1.8/2.7/2.8/3.0/3.15
1.8/2.9
1.8/2.9
3.3
VGEN3
VUSB
250
100
BUCK SWITCHER SUPPLIES
Four buck switchers are provided with integrated power switches and synchronous rectification. In a typical application, SW1
and SW2 are used for supplying the application processor core power domains. Split power domains allow independent DVS
control for processor power optimization, or to support technologies with a mix of device types with different voltage ratings. SW3
is used for powering internal processor memory as well as low voltage peripheral devices and interfaces which can run at the
same voltage level. SW4 is used for powering external memory as well as low voltage peripheral devices and interfaces which
can run at the same voltage level.
An anticipated platform use case applies SW1 and SW2 to processor power domains that require voltage alignment to allow
direct interfacing without bandwidth limiting synchronizers.
The buck switchers have to be supplied from the system supply BP, which is drawn from the main battery or the battery charger
(when present). Figure 16 shows a high level block diagram of the buck switchers.
Figure 16. Buck Switcher Architecture
13892
Analog Integrated Circuit Device Data
72
Freescale Semiconductor
FREESCALE [ Freescale ]
