Datasheet

4
LTC1329-10/
LTC1329-50/LTC1329A-50
TYPICAL PERFORMANCE CHARACTERISTICS
U
W
TEMPERATURE (°C)
0
FULL-SCALE I
OUT
ERROR (LSB)
3
2
1
0
–1
–2
–3
30 50
1329 G05
10 20
40 60 70
V
CC
= 3.3V
V(I
OUT
) = 0.45V
LTC1329-50
LTC1329-10
CODE
0
INL (LSB)
1.0
0.8
0.6
0.4
0.2
0
–0.2
–0.4
–0.6
–0.8
–1.0
64
128
160
1329 • TPC04
32 96
192
224
256
T
A
= 25°C
V
CC
= 3.3V
V(I
OUT
) = 0.45V
LTC1329-10/LTC1329-50 Full-
Scale Current vs Temperature
SUPPLY VOLTAGE (V)
0
FULL-SCALE I
OUT
ERROR (LSB)
2
1
0
–1
–2
35
1329 G06
12
467
T
A
= 25°C
V(I
OUT
) = 0.45V
LTC1329-50
LTC1329-10
LTC1329-10/LTC1329-50
Supply Voltage RejectionLTC1329-50 INL vs Code
PIN FUNCTIONS
UUU
I
OUT
(Pin 1): DAC Current Output. In 3.3V or 5V systems,
the DAC current output can be biased from –15V to 2V or
–15V to 2.5V respectively.
V
CC
(Pin 2): Voltage Supply (2.7V ≤ V
CC
≤ 6.5V). This
supply must be kept free from noise and ripple by bypass-
ing directly to the ground plane.
SHDN (Pin 3): Shutdown. A logic low puts the chip
into Shutdown mode. The digital setting for the DAC is
retained.
CLK (Pin 4): Shift Clock. This clock synchronizes the serial
data in 3-wire mode. This pin has a Schmitt trigger input.
CS (Pin 5): Chip Select Input. In 3-wire mode, a logic low
on this CS pin enables the LTC1329. Upon power-up, a
logic high at CS puts the chip into pulse mode. If CS ever
goes low, the chip is configured in 3-wire mode until the
next power is cycled.
GND (Pin 6): Ground. Ground should be tied directly to a
ground plane.
D
IN
(UP/DN)(Pin 7): Data Input. In 3-wire mode, the DAC
data is shifted into D
IN
on the rising edge of CLK. In pulse
mode, upon power-up a logic high at D
IN
puts the counter
into increment-only mode. If D
IN
ever goes low, the
I
OUT
BIAS VOLTAGE (V)
–15
FULL-SCALE I
OUT
ERROR (LSB)
0.5
0.4
0.3
0.2
0.1
0
–0.1
–0.2
–0.3
–0.4
–0.5
–6 0
1329 G07
–12 –9
–3 3 6
T
A
= 25°C
V
CC
= 3.3V
LTC1329-50
LTC1329-10
LTC1329-10/LTC1329-50
Bias Voltage Rejection
(Full-Scale Current)
I
OUT
BIAS VOLTAGE (V)
–15
ZERO-SCALE I
OUT
CURRENT (nA)
50
40
30
20
10
0
–10
–20
–30
–40
–50
–6 0
1329 G08
–12 –9
–3 3 6
LTC1329-10
LTC1329-50
LTC1329-10/LTC1329-50
Bias Voltage Rejection
(Zero-Scale Current)
SUPPLY VOLTAGE (V)
2.7
MAXIMUM I
OUT
BIAS VOLTAGE (V)
6.5
6.0
5.5
5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
3.7
4.7
5.2
1329 • TPC09
3.2 4.2
5.7
6.2
6.7
T
A
= 25°C
I
OUT
= FULL-SCALE CURRENT
Maximum I
OUT
Bias Voltage
vs Supply Voltage