Datasheet

 2006-2012 Microchip Technology Inc. . DS39662E-page 81
ENC28J60
TABLE 16-1: AC CHARACTERISTICS: ENC28J60 (INDUSTRIAL AND COMMERCIAL)
TABLE 16-2: OSCILLATOR TIMING CHARACTERISTICS
TABLE 16-3: RESET AC CHARACTERISTICS
TABLE 16-4: CLKOUT PIN AC CHARACTERISTICS
TABLE 16-5: REQUIREMENTS FOR EXTERNAL MAGNETICS
AC CHARACTERISTICS
Standard Operating Conditions
-40°C T
A +85°C, 3.10V VDD 3.60V (Industrial)
0°C T
A +70°C, 3.10V VDD 3.60V (Commercial)
Param.
No.
Sym Characteristic Min Max Units Conditions
F
OSC Clock In Frequency 25 25 MHz
T
OSC Clock In Period 40 40 ns
TDUTY Duty Cycle
(external clock input)
40 60 %
f Clock Tolerance — 50 ppm
Param.
No.
Sym Characteristic Min Max Units Conditions
trl RESET
Pin High Time
(between Reset events)
2—s
tRSTLOW RESET Pin Low Time to
Trigger Reset
400 — ns
Param.
No.
Sym Characteristic Min Max Units Conditions
t
h
CLKOUT
CLKOUT Pin High Time 16.5 — ns TDUTY = 50% (Note 1)
t
l
CLKOUT
CLKOUT Pin Low Time 16.5 — ns TDUTY = 50% (Note 1)
t
r
CLKOUT CLKOUT Pin Rise Time — 3 ns Measured from 0.1 VDD to
0.9 V
DD, Load = 10 pF (Note 1)
t
f
CLKOUT
CLKOUT Pin Fall Time — 4 ns Measured from 0.9 VDD to
0.1 V
DD, Load = 10 pF (Note 1)
Note 1: CLKOUT prescaler is set to divide by one.
Parameter Min Norm Max Units Conditions
RX Transformer Turns Ratio — 1:1 — —
TX Transformer Turns Ratio — 1:1 — — Transformer Center Tap = 3.3V
Insertion Loss 0.0 0.6 1.1 dB
Primary Inductance 350 — — H 8 mA bias
Transformer Isolation — 1.5 — kV
Differential to Common Mode Rejection 40 — — dB 0.1 to 10 MHz
Return Loss -16 — — dB