MPT612 NXP Semiconductors, MPT612 Datasheet - Page 15

• Manufacturer Part Number: MPT612
• Description: The MPT612, the first dedicated IC for performing the Maximum Power Point Tracking (MPPT) function, is designed for use in applications that use solar photovoltaic (PV) cells or in fuel cells
• Manufacturer: NXP Semiconductors

NXP Semiconductors
MPT612
Product data sheet
7.17.1 Crystal oscillator
7.17.2 PLL
7.15 Watchdog timer
7.16 Real-time clock
7.17 System control
The purpose of the watchdog timer is to reset the processor core after a given time if it
enters an error state. When enabled, the watchdog generates a system reset if the user
program fails to reload the watchdog within the predetermined time. The watchdog timer
provides the following features:
The Real-Time Clock (RTC) is designed to provide a set of counters to measure time
when normal or idle operating mode is selected. The RTC has been designed to use
minimal power, making it suitable for battery powered systems where the CPU is not
running continuously (idle mode). The RTC provides the following features:
The on-chip integrated oscillator operates with external crystal in range of 1 MHz to
25 MHz. The oscillator output frequency is f
CCLK. f
The PLL accepts an input clock frequency in the range of 10 MHz to 25 MHz. The input
frequency is multiplied up into the range of 10 MHz to 70 MHz by a Current Controlled
Oscillator (CCO).
The multiplier can be an integer value from 1 to 32. In practice however, the multiplier
value cannot be higher than 6 on this family of processor cores due to the CPUs upper
frequency limit.
The CCO operates in a range from 156 MHz to 320 MHz, this forms an additional divider
in the loop to keep the CCO within its frequency range while the PLL is providing the
required output frequency.
• Internal device reset if not periodically reloaded
• Debug mode
• Enabled by software but requires a hardware reset or watchdog reset/interrupt to be
• Incorrect/Incomplete feed sequence causes reset/interrupt, if enabled
• Flag to indicate watchdog reset
• Programmable 32-bit timer with internal prescaler
• Selectable time period from (T
• Measures the passage of time to maintain a calendar and clock
• Ultra-low power design to support battery powered systems
• Provides seconds, minutes, hours, day of the month, month, year, day of the week
• Uses either the dedicated internal 32 kHz RTC oscillator input or the clock derived
• The programmable reference clock divider allows fine adjustment of the RTC
• Dedicated power supply pin can be connected to a battery or the main 3.3 V supply
disabled.
T
and day of the year
from the external crystal/oscillator input on pin XTAL1
PCLK
osc
× 4.
and CCLK are the same value unless the PLL is running and connected.
All information provided in this document is subject to legal disclaimers.
Rev. 2 — 14 September 2010
PCLK
× 256 × 4) to (T
osc
and the ARM processor clock frequency is
Maximum power point tracking IC
PCLK
× 232 × 4) in multiples of
© NXP B.V. 2010. All rights reserved.
MPT612
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