
ADMC401
–5–
REV. B
Parameter
Min
Max
Unit
Clock Signals
t
CK is defined as 0.5tCKI. The ADMC401 uses an input clock
with a frequency equal to half the instruction rate; a 13 MHz
clock (which is equivalent to 76.9 ns) yields a 38.5 ns processor
cycle (equivalent to 26 MHz). t
CK values within the range of
0.5t
CKI period should be substituted for all relevant timing
parameters to obtain specification value.
Example: t
CKH = 0.5tCK – 10 ns = 0.5 (38.5 ns) – 10 ns = 9.25 ns.
Timing Requirements:
t
CKI
CLKIN Period
76.9
150
ns
t
CKIL
CLKIN Width Low
20
ns
t
CKIH
CLKIN Width High
20
ns
Switching Characteristics:
t
CKL
CLKOUT Width Low
0.5t
CK – 10
ns
t
CKH
CLKOUT Width High
0.5t
CK – 10
ns
t
CKOH
CLKIN High to CLKOUT High
0
20
ns
Control Signals
Timing Requirement:
t
RSP
RESET Width Low
5t
CK
1
ns
PWM Shutdown Signals
Timing Requirements:
tPWMTPW
PWMTRIP Width Low
tCK
ns
tPIOPWM
PIO Width Low
2tCK
ns
ADC Signals
Timing Requirements:
tCSI
Internal Convert Start Width High
2tCK
ns
tCSE
External Convert Start Width High
2tCK
ns
NOTE
1Applies after power-up sequence is complete. Internal phase lock loop requires no more than 2000 CLKIN cycles assuming stable CLKIN (not including crystal
oscillator start-up time).
CLKIN
CLKOUT
tCKOH
tCKI
tCKIH
tCKIL
tCKH
tCKL
Figure 1. Clock Signals