Datasheet
dsPIC33EPXXXGP50X, dsPIC33EPXXXMC20X/50X AND PIC24EPXXXGP/MC20X
DS70000657H-page 414 2011-2013 Microchip Technology Inc.
FIGURE 30-2: EXTERNAL CLOCK TIMING
Q1 Q2 Q3 Q4
OSC1
CLKO
Q1 Q2 Q3
OS20
OS30 OS30
OS40
OS41
OS31 OS31
Q4
OS25
TABLE 30-17: EXTERNAL CLOCK TIMING REQUIREMENTS
AC CHARACTERISTICS
Standard Operating Conditions: 3.0V to 3.6V
(unless otherwise stated)
Operating temperature -40°C TA +85°C for Industrial
-40°C T
A +125°C for Extended
Param
No.
Symb Characteristic Min. Typ.
(1)
Max. Units Conditions
OS10 F
IN External CLKI Frequency
(External clocks allowed only
in EC and ECPLL modes)
DC — 60 MHz EC
Oscillator Crystal Frequency 3.5
10
—
—
10
25
MHz
MHz
XT
HS
OS20 T
OSC TOSC = 1/FOSC 8.33 — DC ns +125ºC
TOSC = 1/FOSC 7.14 — DC ns +85ºC
OS25 T
CY Instruction Cycle Time
(2)
16.67 — DC ns +125ºC
Instruction Cycle Time
(2)
14.28 — DC ns +85ºC
OS30 TosL,
To sH
External Clock in (OSC1)
High or Low Time
0.45 x TOSC — 0.55 x TOSC ns EC
OS31 TosR,
To sF
External Clock in (OSC1)
Rise or Fall Time
— — 20 ns EC
OS40 TckR CLKO Rise Time
(3,4)
—5.2—ns
OS41 TckF CLKO Fall Time
(3,4)
—5.2—ns
OS42 GM External Oscillator
Transconductance
(4)
— 12 — mA/V HS, VDD = 3.3V,
T
A = +25ºC
—6—mA/VXT, VDD = 3.3V,
T
A = +25ºC
Note 1: Data in “Typical” column is at 3.3V, +25°C unless otherwise stated.
2: Instruction cycle period (TCY) equals two times 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
“Minimum” values with an external clock applied to the OSC1 pin. When an external clock input is used,
the “Maximum” cycle time limit is “DC” (no clock) for all devices.
3: Measurements are taken in EC mode. The CLKO signal is measured on the OSC2 pin.
4: This parameter is characterized, but not tested in manufacturing.