LTC1298CS8 Linear Technology, LTC1298CS8 Datasheet

IC A/D CONV SAMPLING 12BIT 8SOIC

LTC1298CS8

Manufacturer Part Number
LTC1298CS8
Description
IC A/D CONV SAMPLING 12BIT 8SOIC
Manufacturer
Linear Technology
Datasheet

Specifications of LTC1298CS8

Number Of Bits
12
Sampling Rate (per Second)
11.1k
Data Interface
MICROWIRE™, Serial, SPI™
Number Of Converters
1
Power Dissipation (max)
1.8mW
Voltage Supply Source
Single Supply
Operating Temperature
0°C ~ 70°C
Mounting Type
Surface Mount
Package / Case
8-SOIC (0.154", 3.90mm Width)
Lead Free Status / RoHS Status
Contains lead / RoHS non-compliant

Available stocks

Company
Part Number
Manufacturer
Quantity
Price
Part Number:
LTC1298CS8
Manufacturer:
LINEAR/凌特
Quantity:
20 000
FEATURES
APPLICATIONS
TYPICAL APPLICATIONS
0V TO 5V RANGE
ANALOG INPUT
12-Bit Resolution
8-Pin SOIC Plastic Package
Low Cost
Low Supply Current: 250 A Typ.
Auto Shutdown to 1nA Typ.
Guaranteed 3/4LSB Max DNL
Single Supply 5V to 9V Operation
On-Chip Sample-and-Hold
60 s Conversion Time
Sampling Rates:
I/O Compatible with SPI, Microwire, etc.
Differential Inputs (LTC1286)
2-Channel MUX (LTC1298)
3V Versions Available: LTC1285/LTC1288
Battery-Operated Systems
Remote Data Acquisition
Battery Monitoring
Handheld Terminal Interface
Temperature Measurement
Isolated Data Acquisition
12.5 ksps (LTC1286)
11.1 ksps (LTC1298)
Samples at 200Hz and Runs Off a 5V Supply
1
2
3
4
25 W, S0-8 Package, 12-Bit ADC
V
+IN
–IN
GND
REF
LTC1286
U
CS/SHDN
D
CLK
V
OUT
CC
4.7 F
8
7
6
5
5V
U
SERIAL DATA LINK
N
(e.g., 8051)
P1.4
P1.3
P1.2
LTC1286/98 • TA01
MPU
The LTC1286/LTC1298 are micropower, 12-bit, succes-
sive approximation sampling A/D converters. They typi-
cally draw only 250 A of supply current when converting
and automatically power down to a typical supply current
of 1nA whenever they are not performing conversions.
They are packaged in 8-pin SO packages and operate on
5V to 9V supplies. These 12-bit, switched-capacitor, suc-
cessive approximation ADCs include sample-and-holds.
The LTC1286 has a single differential analog input. The
LTC1298 offers a software selectable 2-channel MUX.
On-chip serial ports allow efficient data transfer to a wide
range of microprocessors and microcontrollers over three
wires. This, coupled with micropower consumption, makes
remote location possible and facilitates transmitting data
through isolation barriers.
These circuits can be used in ratiometric applications or
with an external reference. The high impedance analog
inputs and the ability to operate with reduced spans (to
1.5V full scale) allow direct connection to sensors and
transducers in many applications, eliminating the need for
gain stages.
DESCRIPTION
12-Bit A/D Converters In
1000
100
10
Micropower Sampling
Supply Current vs Sample Rate
1
0.1k
T
V
f
CLK
A
CC
= 25°C
= V
= 200kHz
U
REF
SAMPLE FREQUENCY (Hz)
LTC1286/LTC1298
= 5V
1k
S0-8 Packages
10k
LTC1286/98 • TA02
100k
1

Related parts for LTC1298CS8

LTC1298CS8 Summary of contents

Page 1

FEATURES 12-Bit Resolution 8-Pin SOIC Plastic Package Low Cost Low Supply Current: 250 A Typ. Auto Shutdown to 1nA Typ. Guaranteed 3/4LSB Max DNL Single Supply Operation On-Chip Sample-and-Hold 60 s Conversion Time Sampling Rates: 12.5 ksps ...

Page 2

... CLK LTC1286CS8 6 D OUT LTC1286IS8 5 CS/SHDN PART MARKING S8 PACKAGE 1286 = 175 C/W JA 1286I TOP VIEW ORDER PART NUMBER REF 7 CLK LTC1298CS8 D 6 OUT LTC1298IS8 PART MARKING S8 PACKAGE 1298 = 175 C/W JA 1298I MIN TYP MAX 4.5 9.0 4.5 5.5 (Note 4) 200 = 200kHz 80 ...

Page 3

CONVERTER AND MULTIPLEXER CHARACTERISTICS PARAMETER Resolution (No Missing Codes) Integral Linearity Error Differential Linearity Error Offset Error Gain Error Analog Input Range REF Input Range (LTC1286) (Notes 7, 8, and 9) Analog Input Leakage Current (Note 10) ...

Page 4

LTC1286/LTC1298 AC CHARACTERISTICS SYMBOL PARAMETER t Analog Input Sample Time SMPL f Maximum Sampling Frequency SMPL (MAX) t Conversion Time CONV t Delay Time, CLK to D Data Valid dDO OUT t Delay Time Hi-Z dis OUT ...

Page 5

W U TYPICAL PERFORMANCE CHARACTERISTICS Reference Current vs Sample Rate (LTC1286) 100 T = 25° REF 200kHz CLK ...

Page 6

LTC1286/LTC1298 W TYPICAL PERFORMANCE CHARACTERISTICS Spurious Free Dynamic Range vs Frequency 100 25° REF 12.5kHz SMPL 0 1k 10k 100k ...

Page 7

W U TYPICAL PERFORMANCE CHARACTERISTICS Minimum Clock Frequency for 0.1 LSB Error vs Temperature 200 REF 150 100 50 0 –55 –35 – TEMPERATURE (°C) LT1286/98 • G14 U ...

Page 8

LTC1286/LTC1298 W BLOCK DIAGRAM + IN (CH0) – IN (CH1) TEST CIRCUITS Load Circuit for dDO 1. OUT 100pF Voltage Waveforms for D Delay Times, t OUT CLK dDO D OUT 8 ...

Page 9

TEST CIRCUITS Voltage Waveforms for OUT WAVEFORM 1 (SEE NOTE 1) D OUT WAVEFORM 2 (SEE NOTE 2) NOTE 1: WAVEFORM 1 IS FOR AN OUTPUT WITH INTERNAL CONDITIONS SUCH THAT THE OUTPUT IS HIGH UNLESS DISABLED ...

Page 10

LTC1286/LTC1298 U U APPLICATION INFORMATION SERIAL INTERFACE The 2-channel LTC1298 communicates with micropro- cessors and other external circuitry via a synchronous, half duplex, 4-wire serial interface. The single channel LTC1286 uses a 3-wire interface (see Operating Sequence in Figures 1 ...

Page 11

U U APPLICATION INFORMATION SHIFT MUX ADDRESS IN MSB-First Data (MSBF = suCS CLK ODD/ START SIGN D IN SGL/ MSBF DIFF NULL HI-Z BIT D OUT B11 B10 (MSB) SMPL MSB-First Data (MSBF ...

Page 12

LTC1286/LTC1298 U U APPLICATION INFORMATION Input Data Word The LTC1286 requires no D word permanently IN configured to have a single differential input. The conver- sion result appears on the D line. The data format is OUT MSB ...

Page 13

U U APPLICATION INFORMATION CS 1 CLK DATA ( START IN OUT MPU CONTROLS DATA LINE AND SENDS MUX ADDRESS TO LTC1298 Figure 3. LTC1298 Operation with D ACHIEVING MICROPOWER PERFORMANCE With typical operating currents of 250 A ...

Page 14

LTC1286/LTC1298 U U APPLICATION INFORMATION 25° REF (AFTER CONVERSION 0.002 ...

Page 15

APPLICATION INFORMATION BOARD LAYOUT CONSIDERATIONS Grounding and Bypassing The LTC1286/LTC1298 are easy to use if some care is taken. They should be used with an analog ground plane and single point grounding techniques. The GND pin should ...

Page 16

LTC1286/LTC1298 U U APPLICATION INFORMATION Differential Inputs With differential inputs, the ADC no longer converts just a single voltage but rather the difference between two volt- ages. In this case, the voltage on the selected “+” input is still sampled ...

Page 17

APPLICATION INFORMATION will slow the settling of the inputs important that the overall RC time constants be short enough to allow the analog inputs to completely settle within the allowed time. RC Input Filtering It ...

Page 18

LTC1286/LTC1298 U U APPLICATION INFORMATION 0.2V reference. If this offset is unacceptable, it can be corrected digitally by the receiving system or by offsetting the “–” input of the LTC1286. Noise with Reduced V REF The total input referred noise ...

Page 19

APPLICATION INFORMATION 25° 200kHz CLK 12.5kHz SMPL 100 INPUT FREQUENCY (kHz) ...

Page 20

LTC1286/LTC1298 TYPICAL APPLICATIONS MICROPROCESSOR INTERFACES The LTC1286/LTC1298 can interface directly without ex- ternal hardware to most popular microprocessor (MPU) synchronous serial formats (see Table 1 MPU without a dedicated serial port is used, then ...

Page 21

TYPICAL APPLICATIONS CS CLK OUT MPU TRANSMIT WORD BYTE 1 MPU ? ? ? ? ? ? ? RECEIVED WORD BYTE 1 D OUT FROM LTC1298 STORED IN MC68HC11 RAM ...

Page 22

LTC1286/LTC1298 TYPICAL APPLICATIONS Interfacing to the Parallel Port of the INTEL 8051 Family The Intel 8051 has been chosen to demonstrate the interface between the LTC1298 and parallel port micro- processors. Normally the CS, CLK and D be generated on ...

Page 23

... Figure 14. Scope Trace the LTC1286 “Quick Look” Circuit Showing A/D Output 101010101010 (AAA Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. U ...

Page 24

... MIN 0.189 – 0.197* (4.801 – 5.004 0.228 – 0.244 (5.791 – 6.197 sn128698 128698fs LT/GP 0394 10K • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 1994 0.250 ± 0.010 0.150 – 0.157* (3.810 – 3.988) 4 SO8 0294 ...

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