Datasheet

3
LTC1657/LTC1657L
The ● denotes specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
CC
= 4.5V to 5.5V (LTC1657), V
CC
= 2.7V to 5.5V (LTC1657L),
V
OUT
unloaded, REFOUT tied to REFHI, REFLO tied to GND, X1/X2 tied to GND, unless otherwise noted.
ELECTRICAL CHARACTERISTICS
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Op Amp DC Performance
Short-Circuit Current Low V
OUT
Shorted to GND ● 70 120 mA
Short-Circuit Current High V
OUT
Shorted to V
CC
● 80 140 mA
Output Impedance to GND Input Code = 0 (LTC1657) ● 40 120 Ω
Input Code = 0 (LTC1657L)
● 120 275 Ω
Output Line Regulation Input Code = 65535, LTC1657: V
CC
= 4.5V to 5.5V ● 4 mV/V
Input Code = 65535, LTC1657L: V
CC
= 2.7V to 5.5V ● 3 mV/V
AC Performance
Voltage Output Slew Rate (Note 5) ● ±0.3 ±0.7 V/µs
Voltage Output Settling Time (Note 5) to 0.0015% (16-Bit Settling Time) 20 µs
(Note 5) to 0.012% (13-Bit Settling Time) 10 µs
Digital Feedthrough (Note 6) 0.3 nV•s
Midscale Glitch Impulse DAC Switch Between 8000
H
and 7FFF
H
8nV•s
Output Voltage Noise Using X1/X2 Tied to V
OUT
(Notes 8, 9)
Internal Reference at 1kHz LTC1657 165 nV/√Hz
LTC1657L 105 nV/√Hz
Output Voltage Noise Using X1/X2 Tied to V
OUT
(Notes 8, 9, 10) 50 nV/√Hz
External Reference at 1kHz
Output Voltage Noise Density Using X1/X2 Tied to V
OUT
(Notes 8, 9) 8 µV
P-P
Internal Reference from 0.1Hz to 10Hz
Refererence Input Multiplying BW 700 kHz
Reference Output (REFOUT)
Reference Output Voltage LTC1657 ● 2.036 2.048 2.060 V
LTC1657L
● 1.240 1.250 1.260 V
Reference Output 15 ppm/°C
Temperature Coefficient
Reference Line Regulation LTC1657: V
CC
= 4.5V to 5.5V ● ±1.5 mV/V
LTC1657L: V
CC
= 2.7V to 5.5V ● ±1.0 mV/V
Reference Load Regulation Measured at I
OUT
= 100µA (LTC1657) ● 5 mV/A
Measured at I
OUT
= 100µA (LTC1657L) ● 3 mV/A
Short-Circuit Current REFOUT Shorted to GND ● 50 100 mA
Reference Output Voltage Noise at 1kHz LTC1657 150 nV/√Hz
LTC1657L 90 nV/√Hz
Reference Output Voltage Noise Density 6 µV
P-P
from 0.1Hz to 10Hz
Reference Input
REFHI, REFLO Input Range (Note 7) See Applications Information
X1/X2 Tied to V
OUT
● 0V
CC
– 1.5 V
X1/X2 Tied to GND
● 0V
CC
/2 V
REFHI Input Resistance LTC1657 ● 16 25 kΩ
LTC1657L (Relative to REFLO)
● 16 23 kΩ