LTC6945
4
6945f
ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TC = 25°C. VREF+ = VREF0+ = VD+ = VRF+ = VVCO+ = 3.3V, VCP+ = 5V unless otherwise
specified. All voltages are with respect to GND.
SYMBOL
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
Reference (R) Divider
R
Divide Range
All Integers Included
l
1
1023
Counts
VCO (N) Divider
N
Divide Range
All Integers Included
l
32
65535
Counts
Digital Pin Specifications
VIH
High Level Input Voltage
MUTE, CS, SDI, SCLK
l
1.55
V
VIL
Low Level Input Voltage
MUTE, CS, SDI, SCLK
l
0.8
V
VIHYS
Input Voltage Hysteresis
MUTE, CS, SDI, SCLK
250
mV
Input Current
MUTE, CS, SDI, SCLK
l
±1
μA
IOH
High Level Output Current
SDO and STAT, VOH = VD+ – 400mV
l
1.4
2.3
mA
IOL
Low Level Output Current
SDO and STAT, VOL = 400mV
l
1.8
3.4
mA
SDO Hi-Z Current
l
±1
μA
Digital Timing Specifications (See Figures 8 and 9)
tCKH
SCLK High Time
l
25
ns
tCKL
SCLK Low Time
l
25
ns
tCSS
CS Setup Time
l
10
ns
tCSH
CS High Time
l
10
ns
tCS
SDI to SCLK Setup Time
l
6ns
tCH
SDI to SCLK Hold Time
l
6ns
tDO
SCLK to SDO Time
To VIH/VIL/Hi-Z with 30pF Load
l
16
ns
Power Supply Voltages
VREF+ Supply Range
l
3.15
3.3
3.45
V
VREFO+ Supply Range
l
3.15
3.3
3.45
V
VD+ Supply Range
l
3.15
3.3
3.45
V
VRF+ Supply Range
l
3.15
3.3
3.45
V
VVCO+ Supply Range
l
3.15
3.3
3.45
V
VCP+ Supply Range
l
3.15
5.25
V
Power Supply Currents
IDD
VD+ Supply Current
Digital Inputs at Supply Levels
l
250
μA
ICC(CP)
VCP+ Supply Current
ICP = 11.2mA
ICP = 1.0mA
PDALL = 1
l
33
11
235
37
12.3
385
mA
μA
ICC(REFO)
VREFO+ Supply Currents
REFO Enabled, RZ = ∞
l
7.8
9.0
mA
ICC
Sum VREF+, VRF+, VVCO+ Supply
Currents
RF Muted, OD[2:0] = 1
RF Enabled, RFO[1:0] =0, OD[2:0] = 1
RF Enabled, RFO[1:0] = 3, OD[2:0] = 1
RF Enabled, RFO[1:0] =3, OD[2:0] = 2
RF Enabled, RFO[1:0] =3, OD[2:0] = 3
RF Enabled, RFO[1:0] =3, OD[2:0] = 4 to 6
PDALL = 1
l
68
78
87
104
110
115
202
75
85
95
114
121
125
396
mA
μA