LTC1288_15 Datasheet, PDF (6/24 Pages) Linear Technology – 3V Micropower Sampling 12-Bit A/D Converters in SO-8 Packages

LTC1285/LTC1288
TYPICAL PERFORMANCE CHARACTERISTICS
Spurious-Free Dynamic Range
vs Input Frequency
100
90
80
70
60
50
40
30
20
T_A = 25°C
V_CC = 2.7V
10 ^{VREF = 2.5V}
f_SMPL = f_SMPL(MAX)
0
1
10
100
INPUT FREQUENCY (kHz)
LTC1285/88 • G13
4096 Point FFT Plot
0
T_A = 25°C
V_CC = 2.7V
– 20 V_REF = 2.5V
f_IN = 3.05kHz
– 40
f_CLK = 120kHz
f_SMPL = 7.5kHz
– 60
– 80
– 100
– 120
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
FREQUENCY (kHz)
LTC1285/88 • TPC16
Maximum Clock Frequency
vs Source Resistance
200
180
T_A = 25°C
V_CC = 2.7V
160
V_REF = 2.5V
140
120
100
80
V_IN +INPUT
60
40
–INPUT
R_SOURCE–
20
0
0.1
1
10
SOURCE RESISTANCE (kΩ)
LTC1285/88 • G19
S/(N + D) vs Input Level
80
T_A = 25°C
70 ^{VCC = 2.7V}
V_REF = 2.5V
60
f_IN = 1kHz
f_SMPL = f_SMPL(MAX)
50
40
30
20
10
0
– 45 – 40 – 35 – 30 – 25 – 20 – 15 – 10 – 5 0
INPUT LEVEL (dB)
LTC1285/88 • TPC14
Intermodulation Distortion
0
T_A = 25°C
V_CC = 2.7V
– 20 V_REF = 2.5V
f1 = 2.05kHz
– 40
f2 = 3.05kHz
f_SMPL = 7.5kHz
– 60
– 80
– 100
– 120
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
FREQUENCY (kHz)
LTC1285/88 • TPC17
Sample-and-Hold Acquisition
Time vs Source Resistance
10000
T_A = 25°C
V_CC = 2.7V
V_REF = 2.5V
1000
100
1
R_SOURCE+
V_IN
+INPUT
–INPUT
10
100
1000
SOURCE RESISTANCE (Ω)
10000
LTC1285/88 • TPC20
Attenuation vs Input Frequency
0
10
20
30
40
50
60
70
T_A = 25°C
80 V_CC = 2.7V
90
V_REF = 2.5V
f_SMPL = f_SMPL(MAX)
100
1k
10k
100k
1M
10M
INPUT FREQUENCY (Hz)
LTC1285/86 • TPC15
Power Supply Feedthrough
vs Ripple Frequency
0
– 10
T_A = 25°C
V_CC = 2.7V (V_RIPPLE = 1mV)
– 20 ^VREF ^{= 2.5V}
f_CLK = 120kHZ
– 30
– 40
– 50
– 60
– 70
– 80
– 90
–100
1k
10k
100k
1M
10M
RIPPLE FREQUENCY (Hz)
LTC1285/86 • TPC18
Maximum Clock Frequency
vs Supply Voltage
300
280
T_A = 25°C
V_REF = 2.5V
260
240
220
200
180
160
140
120
100
2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0
SUPPLY VOLTAGE (V)
LTC1285/88 • TPC21
6