MCP1631RD-MCC1 Microchip Technology, MCP1631RD-MCC1 Datasheet - Page 71

• Manufacturer Part Number: MCP1631RD-MCC1
• Description: REFERENCE DESIGN FOR MCP1631HV
• Manufacturer: Microchip Technology
• Type: Battery Managementr

Specifications of MCP1631RD-MCC1

• Main Purpose: Power Management, Battery Charger
• Embedded: Yes, MCU, 8-Bit
• Utilized Ic / Part: MCP1631HV, PIC16F883
• Primary Attributes: 1 ~ 2 Cell- Li-Ion, 1 ~ 4 Cell- NiCd/NiMH
• Secondary Attributes: Status LEDs
• Supported Devices: MCP1631HV, PIC16F883 Device Type
• Tool / Board Applications: Power Management-Battery Management
• Development Tool Type: Reference Design
• Input Voltage: 5.5 V to 16 V
• Product: Power Management Modules
• Mcu Supported Families: MCP1631HV/PIC16F883 Family
• Silicon Manufacturer: Microchip
• Silicon Core Number: MCP1631HV
• Kit Application Type: Reference Design
• Application Sub Type: Battery Charger
• Kit Contents: Board Only
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: MCP1631HV, PIC16F883
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

4.6
The system clock source can be switched between
external and internal clock sources via software using
the System Clock Select (SCS) bit of the OSCCON
register.
4.6.1
The System Clock Select (SCS) bit of the OSCCON
register selects the system clock source that is used for
the CPU and peripherals.
• When the SCS bit of the OSCCON register = 0,
• When the SCS bit of the OSCCON register = 1,
4.6.2
The Oscillator Start-up Time-out Status (OSTS) bit of
the OSCCON register indicates whether the system
clock is running from the external clock source, as
defined by the FOSC<2:0> bits in the Configuration
Word Register 1 (CONFIG1), or from the internal clock
source. In particular, OSTS indicates that the Oscillator
Start-up Timer (OST) has timed out for LP, XT or HS
modes.
4.7
Two-Speed Start-up mode provides additional power
savings by minimizing the latency between external
oscillator start-up and code execution. In applications
that make heavy use of the Sleep mode, Two-Speed
Start-up will remove the external oscillator start-up
time from the time spent awake and can reduce the
overall power consumption of the device.
This mode allows the application to wake-up from
Sleep, perform a few instructions using the INTOSC
as the clock source and go back to Sleep without
waiting for the primary oscillator to become stable.
© 2009 Microchip Technology Inc.
the system clock source is determined by
configuration of the FOSC<2:0> bits in the
Configuration Word Register 1 (CONFIG1).
the system clock source is chosen by the internal
oscillator frequency selected by the IRCF<2:0>
bits of the OSCCON register. After a Reset, the
SCS bit of the OSCCON register is always
cleared.
Note:
Note:
Clock Switching
Two-Speed Clock Start-up Mode
SYSTEM CLOCK SELECT (SCS) BIT
Any automatic clock switch, which may
occur from Two-Speed Start-up or Fail-Safe
Clock Monitor, does not update the SCS bit
of the OSCCON register. The user can
monitor the OSTS bit of the OSCCON
register to determine the current system
clock source.
OSCILLATOR START-UP TIME-OUT
STATUS (OSTS) BIT
Executing a SLEEP instruction will abort
the oscillator start-up time and will cause
the OSTS bit of the OSCCON register to
remain clear.
PIC16F882/883/884/886/887
When the oscillator module is configured for LP, XT or
HS modes, the Oscillator Start-up Timer (OST) is
enabled (see Section 4.4.1 “Oscillator Start-up Timer
(OST)”). The OST will suspend program execution until
1024 oscillations are counted. Two-Speed Start-up
mode minimizes the delay in code execution by
operating from the internal oscillator as the OST is
counting. When the OST count reaches 1024 and the
OSTS bit of the OSCCON register is set, program
execution switches to the external oscillator.
4.7.1
Two-Speed Start-up mode is configured by the
following settings:
• IESO (of the Configuration Word Register 1) = 1;
• SCS (of the OSCCON register) = 0.
• FOSC<2:0> bits in the Configuration Word
Two-Speed Start-up mode is entered after:
• Power-on Reset (POR) and, if enabled, after
• Wake-up from Sleep.
If the external clock oscillator is configured to be
anything other than LP, XT or HS mode, then Two-
speed Start-up is disabled. This is because the external
clock oscillator does not require any stabilization time
after POR or an exit from Sleep.
4.7.2
1.
2.
3.
4.
5.
6.
7.
Internal/External Switchover bit (Two-Speed Start-
up mode enabled).
Register 1 (CONFIG1) configured for LP, XT or
HS mode.
Power-up Timer (PWRT) has expired, or
Wake-up from Power-on Reset or Sleep.
Instructions begin execution by the internal
oscillator at the frequency set in the IRCF<2:0>
bits of the OSCCON register.
OST enabled to count 1024 clock cycles.
OST timed out, wait for falling edge of the
internal oscillator.
OSTS is set.
System clock held low until the next falling edge
of new clock (LP, XT or HS mode).
System clock is switched to external clock
source.
TWO-SPEED START-UP MODE
CONFIGURATION
TWO-SPEED START-UP
SEQUENCE
DS41291F-page 69