Datasheet

MCP4921/4922
DS21897A-page 6  2004 Microchip Technology Inc.
AC CHARACTERISTICS (SPI TIMING SPECIFICATIONS)
FIGURE 1-1: SPI™ Input Timing.
Electrical Specifications: Unless otherwise indicated, V
DD
= 2.7V – 5.5V, T
A
= -40 to +125°C.
Typical values are at +25°C.
Parameters Sym Min Typ Max Units Conditions
Schmitt Trigger High-Level
Input Voltage (All digital input
pins)
V
IH
0.7 V
DD
——V
Schmitt Trigger Low-Level
Input Voltage
(All digital input pins)
V
IL
——0.2V
D
D
V
Hysteresis of Schmitt Trigger
Inputs
V
HYS
—0.05V
DD
—
Input Leakage Current I
LEAKAGE
-1 — 1 µASHDN = LDAC = CS = SDI =
SCK + V
REF
= V
DD
or AV
SS
Digital Pin Capacitance
(All inputs/outputs)
C
IN
,
C
OUT
—10—pFV
DD
= 5.0V, T
A
= +25°C,
f
cLK
= 1 MHz (Note 1)
Clock Frequency F
CLK
——20MHzT
A
= +25°C (Note 1)
Clock High Time t
HI
15 — — ns Note 1
Clock Low Time t
LO
15 — — ns Note 1
CS
Fall to First Rising CLK
Edge
t
CSSR
40 — — ns Applies only when CS falls with
CLK high. (Note 1)
Data Input Setup Time t
SU
15 — — ns Note 1
Data Input Hold Time t
HD
10 — — ns Note 1
SCK Rise to CS
Rise Hold
Time
t
CHS
15 — — ns Note 1
CS
High Time t
CSH
15 — — ns Note 1
LDAC
Pulse Width t
LD
100 — — ns Note 1
LDAC
Setup Time t
LS
40 — — ns Note 1
SCK Idle Time before CS
Fall t
IDLE
40 — — ns Note 1
Note 1: By design and characterization, not production tested.
CS
SCK
SI
LDAC
t
CSSR
t
HD
t
SU
t
LO
t
CSH
t
CHS
LSB in
MSB in
t
IDLE
Mode 1,1
Mode 0,0
t
HI
t
LD
t
LS