OM13005,598 NXP Semiconductors, OM13005,598 Datasheet - Page 14

• Manufacturer Part Number: OM13005,598
• Description: BOARD EVAL EM773 METER US PLUG
• Manufacturer: NXP Semiconductors
• Type: Other Power Managementr

Specifications of OM13005,598

• Design Resources: Plug Meter Schematics, Gerber Files USB Dongle Schematics, Gerber Files
• Main Purpose: Power Management, Energy/Power Meter
• Embedded: Yes, MCU, 32-Bit
• Utilized Ic / Part: EM773FHN33,551
• Interface Type: USB
• Maximum Operating Temperature: + 150 C
• Operating Supply Voltage: 1.8 V to 3.6 V
• Product: Power Management Development Tools
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Primary Attributes: -
• Secondary Attributes: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• For Use With/related Products: EM773, OL2381
• Other names: 568-6680

NXP Semiconductors
EM773
Objective data sheet
Fig 4.
watchdog oscillator
system oscillator
IRC oscillator
IRC oscillator
EM773 clock generation block diagram
(system PLL clock select)
7.15.1.1 Internal RC oscillator
7.15.1.2 System oscillator
SYSPLLCLKSEL
Following reset, the EM773 will operate from the Internal RC oscillator until switched by
software. This allows systems to operate without any external crystal and the bootloader
code to operate at a known frequency.
See
The IRC may be used as the clock source for the WDT, and/or as the clock that drives the
PLL and subsequently the CPU. The nominal IRC frequency is 12 MHz. The IRC is
trimmed to 1 % accuracy over the entire voltage and temperature range.
Upon power-up or any chip reset, the EM773 uses the IRC as the clock source. Software
may later switch to one of the other available clock sources.
The system oscillator can be used as the clock source for the CPU, with or without using
the PLL.
The system oscillator operates at frequencies of 1 MHz to 25 MHz. This frequency can be
boosted to a higher frequency, up to the maximum CPU operating frequency, by the
system PLL.
Figure 4
SYSTEM PLL
(main clock select)
MAINCLKSEL
for an overview of the EM773 clock generation.
All information provided in this document is subject to legal disclaimers.
main clock
Rev. 1 — 1 September 2010
watchdog oscillator
watchdog oscillator
system oscillator
SYSTEM CLOCK
IRC oscillator
IRC oscillator
DIVIDER
(WDT clock update enable)
(CLKOUT update enable)
CLKOUTUEN
WDTUEN
system clock
AHBCLKCTRL[1:18]
(AHB clock enable)
CLKOUT PIN CLOCK
UART PERIPHERAL
SPI0 PERIPHERAL
CLOCK DIVIDER
CLOCK DIVIDER
18
WDT CLOCK
DIVIDER
DIVIDER
Energy metering IC
AHB clock 0
(system)
AHB clocks 1 to 18
(memories
and peripherals)
© NXP B.V. 2010. All rights reserved.
EM773
em773_002aae514
SPI0
UART
WDT
CLKOUT pin
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