MCP3909
TIMING CHARACTERISTICS
Electrical Specifications: Unless otherwise indicated, all parameters apply at AVDD = DVDD = 4.5V to 5.5V,
AGND, DGND = 0V, MCLK = 3.58 MHz; TA = -40°C to +85°C.
Parameter
Sym
Min
Typ
Max Units
Comment
Frequency Outputs
FOUT0 and FOUT1 Pulse Width
tFW
—
275
—
ms 984376 MCLK periods
(Logic Low)
(Note 1)
HFOUT Pulse Width
tHW
—
90
—
ms 322160 MCLK periods
(Note 2)
FOUT0 and FOUT1 Pulse Period
tFP
Refer to Equation 4-1
s
HFOUT Pulse Period
tHP
Refer to Equation 4-2
s
FOUT0 to FOUT1 Falling-Edge
tFS2
—
0.5 tFP
—
Time
FOUT0 to FOUT1 Minimum Sepa-
tFS
ration
—
4/MCLK
—
Digital I/O
FOUT0 and FOUT1 Output High
VOH
4.5
—
—
V IOH = 12 mA, DVDD = 5.0V
Voltage
FOUT0 and FOUT1 Output Low
VOL
—
Voltage
—
0.5
V IOL = 12 mA, DVDD = 5.0V
HFOUT and NEG Output High
VOH
4.5
—
—
V IOH = 12 mA, DVDD = 5.0V
Voltage
HFOUT and NEG Output Low
VOL
—
Voltage
—
0.5
V IOL = 12 mA, DVDD = 5.0V
High-Level Input Voltage
(All Digital Input Pins)
VIH
2.4
—
—
V DVDD = 5.0V
Low Level Input Voltage
(All Digital Input Pins)
VIL
—
—
0.85
V DVDD = 5.0V
Input Leakage Current
Pin Capacitance
—
0.1
±1
µA VIN = 0, VIN = DVDD
—
—
10
pF (Note 3)
Serial Interface Timings (Note 4)
Output Data Rate
fADC
— MCLK/256 —
Serial Clock Frequency
fCLK
—
20
MHz VDD = 5V
Window for serial mode entry tWINDOW —
codes
—
8/MCLK — Last bit must be clocked in
before this time.
Window start time for serial
mode entry codes
tWINSET 1/MCLK
—
—
— First bit must be clocked in
after this time.
Serial Clock High Time
tHI
10
—
40
ns
Serial Clock Low Time
tLO
30
—
20
ns
CS Fall to First Rising CLK Edge tSUCS
15
—
—
ns
Data Input Setup Time
tSU
10
—
—
ns
Data Input Hold Time
tHD
—
—
10
ns
CS Rise to Output Disable
tDIS
—
—
150
ns
CLK Fall to Output Data Valid
tDO
—
—
30
ns
Note 1: If output pulse period (tFP) falls below 984376*2 MCLK periods, then tFW = 1/2 tFP.
2: If output pulse period (tHP) falls below 322160*2 MCLK periods, then tHW = 1/2 tHP. When F2, F1, F0
equals 0,1,1, the HFOUT pulse time is fixed at 64 x MCLK periods or 18 µs for MCLK = 3.58 MHz
3: Specified by characterization, not production tested.
4: Serial timings specified and production tested with 180 pF load.
© 2006 Microchip Technology Inc.
DS22025A-page 5