Linear Technology LTC1665, LTC1660 Datasheet

FEATURES

■

Tiny: 8 DACs in the Board Space of an SO-8

■

Micropower: 56µA per DAC Plus
1µA Sleep Mode for Extended Battery Life

■

Pin Compatible 8-Bit LTC1665 and 10-Bit LTC1660

■

Wide 2.7V to 5.5V Supply Range

■

Rail-to-Rail Voltage Outputs Drive 1000pF

■

Reference Range Includes Supply for Ratiometric
0V-to-VCC Output

■

Reference Input Impedance is Constant—
Eliminates External Buffer

U

APPLICATIO S

■

Mobile Communications

■

Remote Industrial Devices

■

Automatic Calibration for Manufacturing

■

Portable Battery-Powered Instruments

■

Trim/Adjust Applications

LTC1665/LTC1660

Micropower Octal

8-Bit and 10-Bit DACs

U

DESCRIPTIO

The 8-bit LTC®1665 and 10-bit LTC1660 integrate eight
accurate, serially addressable digital-to-analog convert­ers (DACs) in tiny 16-pin narrow SSOP packages. Each
buffered DAC draws just 56µA total supply current, yet is
capable of supplying DC output currents in excess of
5mA and reliably driving capacitive loads to 1000pF.
Sleep mode further reduces total supply current to 1µA.

Linear Technology’s proprietary, inherently monotonic
voltage interpolation architecture provides excellent lin­earity while allowing for an exceptionally small external
form factor.

Ultralow supply current, power-saving Sleep mode and
extremely compact size make the LTC1665 and LTC1660
ideal for battery-powered applications, while their ease of
use, high performance and wide supply range make them
excellent choices as general purpose converters.

, LTC and LT are registered trademarks of Linear Technology Corporation.

BLOCK DIAGRA

1GND

2

V

OUT A

V

3 14

OUT B

V

4 13

OUT C

V

5

OUT D

REF

6

7

CS/LD

SCK

8

DAC A DAC H

DAC B DAC G

DAC C DAC F

DAC D DAC E

CONTROL

LOGIC

W

SHIFT REGISTER

ADDRESS
DECODER

16

15

12

11

10

9

1665/60 BD

V

V

V

V

V

CLR

D

D

CC

OUT H

OUT G

OUT F

OUT E

OUT

IN

LTC1665 Differential Nonlinearity (DNL)

0.5
VCC = 5V

0.4

V

= 4.096V

REF

0.3

0.2

0.1

0

LSB

–0.1
–0.2
–0.3
–0.4
–0.5

0 64 128 192 255

CODE

1665/60 G09

LTC1660 Differential Nonlinearity (DNL)

1

VCC = 5V

0.8

V

= 4.096V

REF

0.6

0.4

0.2
0

LSB

–0.2
–0.4
–0.6
–0.8

–1

0 256 512 768 1023

CODE

1665/60 G13

1

LTC1665/LTC1660

WU

A

W

O

LUTEXI TIS

S

A

WUW

ARB

U
G

PACKAGE

/

O

RDER I FOR ATIO

(Note 1)

VCC to GND .............................................. –0.2V to 7.5V

Logic Inputs to GND ................................ –0.2V to 7.5V

V

OUT A

, V

OUT B…VOUT H

,

REF to GND ................................. –0.2V to (VCC + 0.2V)

Maximum Junction Temperature ......................... 125°C

Operating Temperature Range

LTC1665C/LTC1660C ............................ 0°C to 70°C

LTC1665I/LTC1660I .......................... –40°C to 85°C

Storage Temperature Range ................ –65°C to 150°C

Lead Temperature (Soldering, 10 sec)................ 300°C

LECTRICAL C CHARA TERIST

E

ICS

TOP VIEW

1

GND

2

V

OUT A

3

V

OUT B

4

V

OUT C

5

V

OUT D

6

REF

7

CS/LD

8

SCK

GN PACKAGE

16-LEAD PLASTIC SSOP

T

= 125°C, θJA = 150°C/W (GN)

JMAX

T

= 125°C, θJA = 100°C/W (N)

JMAX

Consult factory for Military grade parts.

V

16

CC

V

15

OUT H

V

14

OUT G

V

13

OUT F

V

12

OUT E

CLR

11

D

10

OUT

D

9

IN

N PACKAGE

16-LEAD PDIP

ORDER PART

NUMBER

LTC1665CGN
LTC1665CN
LTC1665IGN
LTC1665IN
LTC1660CGN
LTC1660CN
LTC1660IGN
LTC1660IN

GN PART MARKING

1665
1665I

1660
1660I

The ● denotes specifications which apply over the full operating temperature range, otherwise specifications
are at TA = 25°C. VCC = 2.7V to 5.5V, V

SYMBOL PARAMETER CONDITIONS MIN TYP MAX MIN TYP MAX UNITS
Accuracy

Resolution ● 8 10 Bits

Monotonicity V
DNL Differential Nonlinearity V
INL Integral Nonlinearity V
V

OS

FSE Full-Scale Error VCC = 5V, V

PSR Power Supply Rejection V

Offset Error (Note 7) ● ±10 ±30 ±10 ±30 mV

VOS Temperature Coefficient ● ±15 ±15 µV/°C

Full-Scale Error Temperature Coefficient ● ±30 ±30 µV/°C

≤ VCC, V

REF

unloaded, unless otherwise noted.

OUT

LTC1665 LTC1660

≤ VCC – 0.1V (Note 2) ● 8 10 Bits

REF

≤ VCC – 0.1V (Note 2) ● ±0.1 ±0.5 ±0.2 ±0.75 LSB

REF

≤ VCC – 0.1V (Note 2) ● ±0.2 ±1.0 ±0.6 ±2.5 LSB

REF

= 4.096V ● ±1 ±4 ±3 ±15 LSB

REF

= 2.5V 0.045 0.18 LSB/V

REF

U

The ● denotes specifications which apply over the full operating temperature range, otherwise specifications
are at TA = 25°C. VCC = 2.7V to 5.5V, V

SYMBOL PARAMETER CONDITONS MIN TYP MAX UNITS
Reference Input

Input Voltage Range ● 0V

Resistance Not in Sleep Mode ● 35 65 kΩ

Capacitance (Note 6) 15 pF
I

REF

Power Supply

V

CC

I

CC

Reference Current Sleep Mode ● 0.001 1 µA

Positive Supply Voltage For Specified Performance ● 2.7 5.5 V

Supply Current VCC = 5V (Note 3) ● 450 730 µA

≤ VCC, V

REF

unloaded, unless otherwise noted.

OUT

= 3V (Note 3) ● 340 550 µA

V

CC

Sleep Mode (Note 3)

● 13µA

CC

2

V

LTC1665/LTC1660

LECTRICAL C CHARA TERIST

E

ICS

The ● denotes specifications which apply over the full operating temperature range, otherwise specifications
are at TA = 25°C. VCC = 2.7V to 5.5V, V

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
DC Performance

Short-Circuit Current Low V

Short-Circuit Current High V

AC Performance

Voltage Output Slew Rate Rising (Notes 4, 5) 0.60 V/µs

Voltage Output Settling Time To ±0.5LSB (Notes 4, 5) 30 µs

Capacitive Load Driving 1000 pF

Digital I/O

V

IH

V

IL

V

OH

V

OL

I

LK

C

IN

Digital Input High Voltage VCC = 2.7V to 5.5V ● 2.4 V

Digital Input Low Voltage VCC = 4.5V to 5.5V ● 0.8 V

Digital Output High Voltage I

Digital Output Low Voltage I

Digital Input Leakage VIN = GND to V

Digital Input Capacitance (Note 6) ● 10 pF

≤ VCC, V

REF

= 0V, VCC = 5.5V, V

OUT

= VCC = 5.5V, V

OUT

Falling (Notes 4, 5) 0.25 V/µs

= 2.7V to 3.6V ● 2.0 V

V

CC

VCC = 2.7V to 5.5V ● 0.6 V

= –1mA, D

OUT

= 1mA, D

OUT

unloaded, unless otherwise noted.

OUT

= 5.1V, Code = Full Scale ● 10 30 100 mA

REF

= 5.1V, Code = 0 ● 10 27 120 mA

REF

Only ● VCC – 1 V

OUT

Only ● 0.4 V

OUT

CC

● ±10 µA

UW

TI I G CHARACTERISTICS

range, otherwise specifications are at TA = 25°C. (See Figure 1)

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
VCC = 4.5V to 5.5V

t

1

t

2

t

3

t

4

t

5

t

6

t

7

t

8

t

9

t

10

t

11

VCC = 2.7V to 5.5V

t

1

t

2

t

3

t

4

t

5

DIN Valid to SCK Setup ● 40 15 ns

DIN Valid to SCK Hold ● 0 –11 ns

SCK High Time (Note 6) ● 30 5 ns

SCK Low Time (Note 6) ● 30 7 ns

CS/LD Pulse Width (Note 6) ● 80 30 ns

LSB SCK High to CS/LD High (Note 6) ● 30 4 ns

CS/LD Low to SCK High (Note 6) ● 80 26 ns

D

Propagation Delay C

OUT

SCK Low to CS/LD Low (Note 6) ● 20 0 ns

CLR Pulse Width (Note 6) ● 100 37 ns

CS/LD High to SCK Positive Edge (Note 6) ● 30 0 ns

SCK Frequency Continuous Square Wave (Note 6) ● 5.00 MHz

DIN Valid to SCK Setup (Note 6) ● 60 20 ns

DIN Valid to SCK Hold (Note 6) ● 0 –14 ns

SCK High Time (Note 6) ● 50 8 ns

SCK Low Time (Note 6) ● 50 12 ns

CS/LD Pulse Width (Note 6) ● 100 30 ns

The ● denotes specifications which apply over the full operating temperature

= 15pF (Note 6) ● 52680ns

LOAD

Continuous 23% Duty Cycle Pulse (Note 6)
Gated Square Wave (Note 6) ● 16.7 MHz

● 7.69 MHz

3

LTC1665/LTC1660

UW

TI I G CHARACTERISTICS

range, otherwise specifications are at TA = 25°C. (See Figure 1)

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

t

6

t

7

t

8

t

9

t

10

t

11

LSB SCK High to CS/LD High (Note 6) ● 50 5 ns

CS/LD Low to SCK High (Note 6) ● 100 27 ns

D

Propagation Delay C

OUT

SCK Low to CS/LD Low (Note 6) ● 30 0 ns

CLR Pulse Width (Note 6) ● 120 41 ns

CS/LD High to SCK Positive Edge (Note 6) ● 30 0 ns

SCK Frequency Continuous Square Wave (Note 6) ● 3.85 MHz

The ● denotes specifications which apply over the full operating temperature

= 15pF (Note 6) ● 5 47 150 ns

LOAD

Continuous 28% Duty Cycle Pulse ● 5.55 MHz
Gated Square Wave

● 10 MHz

Note 1: Absolute maximum ratings are those values beyond which the life
of a device may be impaired.

Note 2: Nonlinearity and monotonicity are defined from code 4 to code
255 for the LTC1665 and from code 20 to code 1023 for the LTC1660.
See Applications Information.

Note 3: Digital inputs at 0V or VCC.

Note 5: VCC = V

i.e., codes 26 and 230 for the LTC1665 or codes 102 and 922 for the
LTC1660.

Note 6: Guaranteed by design and not production tested.
Note 7: Measured at code 4 for the LTC1665 and code 20 for the

LTC1660.

Note 4: Load is 10kΩ in parallel with 100pF.

UW

TYPICAL PERFOR A CE CHARACTERISTICS

Midscale Output Voltage
vs Load Current

3

V

= V

REF

CC

CODE = 128 (LTC1665)

2.9
CODE = 512 (LTC1660)

2.8

2.7

2.6

(V)

2.5

OUT

V

2.4

2.3

2.2

2.1

2

–30 –20 –10 0 10 20 30

VCC = 5.5V

VCC = 5V

VCC = 4.5V

I

(mA)

OUT

SINKSOURCE

1665/60 G01

2

1.9

1.8

1.7

1.6

(V)

1.5

OUT

V

1.4

1.3

1.2

1.1
1

–15 – 4–8–12 0 4 8 12 15

= 5V. DAC switched between 0.1VFS and 0.9VFS,

REF

(LTC1665/LTC1660)

Midscale Output Voltage
vs Load Current

V

= V

REF

CC

CODE = 128 (LTC1665)
CODE = 512 (LTC1660)

VCC = 3.6V

VCC = 3V

VCC = 2.7V

SINKSOURCE

I

(mA)

OUT

1665/60 G02

4

UW

LOGIC INPUT VOLTAGE (V)

012345

SUPPLY CURRENT (mA)

1665/60 G07

2

1.6

1.2

0.8

0.4

0

ALL DIGITAL INPUTS
SHORTED TOGETHER

TYPICAL PERFOR A CE CHARACTERISTICS

LTC1665/LTC1660

(LTC1665/LTC1660)

Minimum Supply Headroom vs
Load Current (Output Sourcing)

1400

V

= 4.096V

REF

< 1LSB

∆V

OUT

1200

CODE = 255 (LTC1665)
CODE = 1023 (LTC1660)

1000

(mV)

800

OUT

600

– V

CC

V

400

200

0

0246810

|

I

|

(mA) (Sourcing)

OUT

Large-Signal Step Response Supply Current vs Logic Input Voltage

5

4

3

(V)

OUT

V

2

1

0

0 20406080100

TIME (µs)

VCC= V

10% TO
90% STEP

REF

1665/60 G05

= 5V

125°C

25°C

–55°C

1665/60 G03

Supply Current vs Temperature

500
480
460
440
420
400
380
360

SUPPLY CURRENT (µA)

340
320
300

–55 –35 –15 5 25 45 65 85 105 125

VCC = 5.5V

VCC = 4.5V

VCC = 3.6V

VCC = 2.7V

TEMPERATURE (°C)

Minimum V
Load Current (Output Sinking)

1400

VCC = 5V
CODE = 0

1200

1000

800

(mV)

OUT

600

V

400

200

0

0246810

1665/60 G06

OUT

|

I

|

(mA) (Sinking)

OUT

vs

125°C

25°C

–55°C

1665/60 G04

TYPICAL PERFOR A CE CHARACTERISTICS

Integral Nonlinearity (INL)

1

0.8

0.6

0.4

0.2
0

LSB

–0.2
–0.4
–0.6
–0.8

–1

0 64 128 192 255

VCC = 5V

= 4.096V

V

REF

UW

CODE

1665/60 G08

(LTC1665)

Differential Nonlinearity (DNL)

0.5
VCC = 5V

0.4

0.3

0.2

0.1

LSB

–0.1
–0.2
–0.3
–0.4
–0.5

= 4.096V

V

REF

0

0 64 128 192 255

CODE

1665/60 G09

5