Datasheet

LTC6946
4
6946fa
ELECTRICAL CHARACTERISTICS
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
C
= 25°C. V
REF
+
= V
REF0
+
= V
D
+
= V
RF
+
= 3.3V, V
CP
+
= V
VCO
+
= 5V unless otherwise
specified (Note 2). All voltages are with respect to GND.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Output Current vs Output Voltage
Sensitivity
(Note 5)
l
0.1 0.5 %/V
Output Current vs Temperature V
CP
= V
CP
+
/2
l
170 ppm/°C
Output Hi-Z Leakage Current I
CP
= 700μA, CPCLO = CPCHI = 0 (Note 5)
I
CP
= 11.2mA, CPCLO = CPCHI = 0 (Note 5)
0.5
5
nA
nA
V
CLMP(LO)
Low Clamp Voltage CPCLO = 1 0.84 V
V
CLMP(HI)
High Clamp Voltage CPCHI = 1, Referred to V
CP
+
–0.96 V
V
MID
Mid-Supply Output Bias Ratio Referred to (V
CP
+
– GND) 0.48 V/V
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
V
IH
High Level Input Voltage MUTE, CS, SDI, SCLK
l
1.55 V
V
IL
Low Level Input Voltage MUTE, CS, SDI, SCLK
l
0.8 V
V
IHYS
Input Voltage Hysteresis MUTE, CS, SDI, SCLK 250 mV
Input Current MUTE, CS, SDI, SCLK
l
±1 μA
I
OH
High Level Output Current SDO and STAT, V
OH
= V
D
+
– 400mV
l
1.4 2.3 mA
I
OL
Low Level Output Current SDO and STAT, V
OL
= 400mV
l
1.8 2.6 mA
SDO Hi-Z Current
l
±1 μA
Digital Timing Specifications (See Figures 7 and 8)
t
CKH
SCLK High Time
l
25 ns
t
CKL
SCLK Low Time
l
25 ns
t
CSS
CS Setup Time
l
10 ns
t
CSH
CS High Time
l
10 ns
t
CS
SDI to SCLK Setup Time
l
6ns
t
CH
SDI to SCLK Hold Time
l
6ns
t
DO
SCLK to SDO Time To V
IH
/V
IL
/Hi-Z with 30pF Load
l
16 ns
Power Supply Voltages
V
REF
+
Supply Range
l
3.15 3.3 3.45 V
V
REFO
+
Supply Range
l
3.15 3.3 3.45 V
V
D
+
Supply Range
l
3.15 3.3 3.45 V
V
RF
+
Supply Range
l
3.15 3.3 3.45 V
V
VCO
+
Supply Range
l
4.75 5.0 5.25 V
V
CP
+
Supply Range
l
4.0 5.25 V
Power Supply Currents
I
DD
V
D
+
Supply Current Digital Inputs at Supply Levels
l
250 μA
I
CC(5V)
Sum V
CP
+
, V
VCO
+
Supply Currents I
CP
= 11.2mA
I
CP
= 1.0mA
PDALL = 1
l
l
l
49
27
405
61
37
660
mA
mA
μA
I
CC(REFO)
V
REFO
+
Supply Currents
REFO Enabled, R
Z
= ∞
l
7.8 9.0 mA