Datasheet
© 2009-2011 Microchip Technology Inc. DS61156G-page 195
PIC32MX5XX/6XX/7XX
TABLE 31-17: EXTERNAL CLOCK TIMING REQUIREMENTS
AC CHARACTERISTICS
Standard Operating Conditions: 2.3V to 3.6V
(unless otherwise stated)
Operating temperature -40°C ≤ TA ≤ +85°C for Industrial
-40°C
≤ TA ≤ +105°C for V-Temp
Param.
No.
Symbol Characteristics Min. Typical
(1)
Max. Units Conditions
OS10 FOSC External CLKI Frequency
(External clocks allowed only
in EC and ECPLL modes)
DC
4
—
—
50
50
MHz
MHz
EC (Note 4)
ECPLL
(Note 3)
OS11 Oscillator Crystal Frequency 3 — 10 MHz XT
(Note 4)
OS12 4 — 10 MHz XTPLL
(Notes 3,4)
OS13 10 — 25 MHz HS
(Note 5)
OS14 10 — 25 MHz HSPLL
(Notes 3,4)
OS15 32 32.768 100 kHz SOSC
(Note 4)
OS20 TOSC TOSC = 1/FOSC = TCY
(2)
— — — — See parameter
OS10 for F
OSC
value
OS30 T
OSL,
T
OSH
External Clock
In (OSC1)
High or Low Time
0.45 x TOSC ——nsEC (Note 4)
OS31 TOSR,
T
OSF
External Clock
In (OSC1)
Rise or Fall Time
— — 0.05 x TOSC ns EC (Note 4)
OS40 TOST Oscillator Start-up Timer Period
(Only applies to HS, HSPLL,
XT, XTPLL and S
OSC Clock
Oscillator modes)
—1024—T
OSC (Note 4)
OS41 TFSCM Primary Clock Fail Safe
Time-out Period
—2—ms(Note 4)
OS42 GM External Oscillator
Transconductance
—12—mA/VVDD = 3.3V,
T
A = +25°C
(Note 4)
Note 1:
Data in “Typical” column is at 3.3V, 25°C unless otherwise stated. Parameters are characterized but are
not tested.
2: Instruction cycle period (TCY) equals the input oscillator time base period. All specified values are based on
characterization data for that particular oscillator type under standard operating conditions with the device
executing code. Exceeding these specified limits may result in an unstable oscillator operation and/or
higher than expected current consumption. All devices are tested to operate at “min.” values with an
external clock applied to the OSC1/CLKI pin.
3: PLL input requirements: 4 MHZ ≤ FPLLIN ≤ 5 MHZ (use PLL prescaler to reduce FOSC). This parameter is
characterized, but tested at 10 MHz only at manufacturing.
4: This parameter is characterized, but not tested in manufacturing.