LINEAR TECHNOLOGY LTC2757 Technical data

±1LSB 18-Bit DAC

1.0
±10V Range

0.8

0.6

Parallel

I/O

V

OUT

LTC2757

±10V

2.1µs Settling

Guaranteed ±1LSB INL & DNL Over Temperature

The LTC®2757 is the first monolithic 18-bit DAC to offer precision DC specifications of ±1LSB INL (max) and ±1LSB DNL (max).
The LTC2757 provides better than ±4ppm accuracy over four bipolar and two unipolar output ranges for precision adjustment in
open loop applications. Excellent temperature drift and power supply rejection simplify system design.

0.4

0.2

0

INL (LSB)

–0.2

–0.4

–0.6

–0.8

–1.0

0 65536

90°C
25°C
–45°C

131072 196608 262143

CODE

Features

n

Program or Pin-Strap Six Output Ranges:

0V to 5V, 0V to 10V, –2.5V to 7.5V, ±2.5V, ±5V, ±10V

n

 18-BitSettlingTime:2.1μs

n

 GlitchImpulse:1.4nV•s(3V),3nV•s(5V)

n

Output Noise: 14nV/√Hz with LT®1468 Output Amp

n

1MHz Reference Multiplying Bandwidth

n

Temperature Drift:
n ±0.2 LSB INL Drift from –40°C to 85°C
n ±0.25 ppm/°C Gain Drift
n ±0.15 ppm/°C Bipolar Zero Drift

n

Power Supply Rejection: ±0.8 LSB/V

n

Voltage-Controlled Offset and Gain Trims

n

Parallel Interface with Readback of All Registers

n

Reset to 0V Regardless of Output Range

n

2.7V to 5.5V Single Supply Operation

n

Maximum Supply Current: 1µA

n

48-Pin 7mm × 7mm LQFP Package

Applications

n

ATE

n

Precision Instrumentation

n

Galvanometer Scanners

n

DAQ Modules

n

Calibration Equipment

SoftSpan™ Selectable

Output Spans

10V

5V

0

–5V

–10V

L, LT, LTC, LTM, Linear Technology and the Linear logo are
registered trademarks and SoftSpan is a trademark of Linear
Technology Corporation. All other trademarks are the property
of their respective owners.

DAC Architecture

The LTC2757 uses a current output
R-2R or 4-quadrant multiplying DAC
architecture. This architecture offers
many advantages for high precision
applications. The reference load
impedance is constant and can be driven
with an unbuffered reference or a slow low
precision op amp with no impact on static
or dynamic performance.
Internal feedback and level-shift resistors
simplify the output loop design and
eliminate the need for external precision
resistors. The unbuffered output and
selectable voltage range give designers
maximum flexibility to choose the best
amplifier for their applications.

REF

5V

WR

UPD

READ

D/S

CLR

M-SPAN

R

IN

GAIN

ADJUST

R

GE

COM

ADJ

SPAN I/O

S2-S0

150pF

REF

DATA I/O

D17-D0

R

R

OFS

FB

V

OSADJ

OFFSET
ADJUST

I

OUT1

I

OUT2

GND

V

DD

27pF

0.1µF

V

OUT

5V

UPD

5V/DIV

Gated

Settling

Waveform

100µV/DIV

(Averaged)

Final 300µV

500ns/DIV

t

= 1.8µs to 0.0004% (18 Bits)

SETTLE

Single/Dual/Quad, I

Single

Serial I/O

18-Bit

16-Bit

14-Bit

2756

1592

1589

OUT

Fast Settling, Low Noise Output Waveforms

The LTC2757 also offers excellent AC specifications. When

Settling

combined with an LT1468 amplifier, the DAC output settles from a
10V step to within 1LSB in less than 2.1µs. The glitch impulse at

majorcarrytransitionsislimitedto1.4nV•s,andtheoutputnoise

density is 14nV/√Hz. Fast settling and low glitch reduce harmonic
distortion, making it possible to produce higher frequency, lower
noise output waveforms.

R-2R Multiplying DACs

Single

Parallel I/O

2757

2751-16

2751-14

Dual

Serial I/O

2758

2752

Dual

Parallel I/O

2753-16

2753-14

Quad

Serial I/O

2754-16

Quad

Parallel I/O

2755-16

2755-14

12-Bit

1588

www.linear.com/2757 n 1-800-4-LINEAR

2751-12

1590

2753-12

2754-12

2755-12

0312D