Datasheet

LTC2633
14
2633fb
typical perFormance characteristics
Gain Error vs Reference Input
0.1Hz to 10Hz Voltage Noise
DAC to DAC Crosstalk (Dynamic)
Gain Error vs Temperature
Multiplying Bandwidth Noise Voltage vs Frequency
FREQUENCY (Hz)
1k
dB
2
0
–2
–6
–4
–8
–12
–10
–16
–14
–18
100k
2633 G31
1M10k
V
CC
= 5V
V
REF(DC)
= 2V
V
REF(AC)
= 0.2V
P-P
CODE = FULL-SCALE
TEMPERATURE (°C)
–50
GAIN ERROR (%FSR)
1.0
0.5
0
–0.5
–1.0
–25 125100755025
2633 G36
1500
1s/DIV
10µV/DIV
2632 G34
V
CC
= 5V, V
FS
= 2.5V
CODE = MID-SCALE
INTERNAL REFERENCE
T
A
= 25°C unless otherwise noted.
LTC2633
REFERENCE VOLTAGE (V)
1 2.52
GAIN ERROR (%FSR)
0.8
0.4
0.6
0
0.2
–0.4
–0.6
–0.2
–0.8
4.5
2633 G33
5.53.51.5 4 53
V
CC
= 5.5V
GAIN ERROR OF 2 CHANNELS
pin Functions
SCL (Pin 1): Serial Clock Input Pin. Data is shifted into the
SDA pin at the rising edges of the clock. This high impedance
pin requires a pull-up resistor or current source to V
CC
.
CA0 (Pin 2): Chip Address Bit 0. Tie this pin to V
CC
, GND
or leave it floating to select an I
2
C slave address for the
part (see Table 1).
REF (Pin 3): Reference Voltage Input or Output. When
external reference mode is selected, REF is an input (1V ≤
V
REF
≤ V
CC
) where the voltage supplied sets the full-scale
DAC output voltage. When internal reference is selected,
the 10ppm/°C 1.25V (LTC2633-L) or 2.048V (LTC2633-H)
internal reference (half full-scale) is available at the pin.
This output may be bypassed to GND with up to 10µF
(0.1µF is recommended) and must be buffered when
driving external DC load current.
GND (Pin 4): Ground.
V
OUTA
, V
OUTB
(Pins 5,6): DAC Analog Voltage Output.
V
CC
(Pin 7): Supply Voltage Input. 2.7V ≤ V
CC
≤ 5.5V
(LTC2633-L) or 4.5V ≤ V
CC
≤ 5.5V (LTC2633-H). Bypass
to GND with a 0.1µF capacitor.
SDA (Pin 8): Serial Data Bidirectional Pin. Data is shifted
into the SDA pin and acknowledged by the SDA pin. This
pin is high impedance while data is shifted in. Open drain
N-channel output during acknowledgement. SDA requires
a pull-up resistor or current source to V
CC
.
FREQUENCY (Hz)
100 1k
NOISE VOLTAGE (nV/√Hz)
500
300
400
100
200
0
100k
2633 G32
1M10k
V
CC
= 5V
CODE = MID-SCALE
INTERNAL REFERENCE
LTC2633-H
LTC2633-L
SCL
5V/DIV
V
OUT
2mV/DIV
1 DAC
SWITCH 0-FS
2V/DIV
2µs/DIV
2633 G35
9TH CLOCK OF
3RD DATA BYTE
LTC2633-H12, V
CC
= 5V
6.7nV•s TYP