SPT SPT7810ACN, SPT7810AIJ, SPT7810BCN, SPT7810BCU, SPT7810BIJ Datasheet

SPT7810

10-BIT, 20 MSPS, ECL OUTPUT A/D CONVERTER

FEATURES

• Monolithic 20 MSPS Converter

• On-Chip Track/Hold

• Bipolar ±2.0 V Analog Input

• 60 dB SNR @ 1 MHz Input

• Low Power (1.3 W Typical)

• 5 pF input Capacitance

• ECL Outputs

GENERAL DESCRIPTION

The SPT7810 A/D converter is a 10-bit monolithic converter capable of word rates of a minimum of 20 MSPS. On board track/hold function assures excellent dynamic performance without the need for external components. Drive requirement problems are minimized with an input capacitance of only 5 pF.

Inputs and outputs are ECL to provide a higher level of noise immunity in high speed system applications. An overrange output signal is provided to indicate overflow conditions.

BLOCK DIAGRAM

APPLICATIONS

• Medical Imaging

• Professional Video

• Radar Receivers

• Instrumentation

• Electronic Warfare

• Digital Communications

Output data format is straight binary. Power dissipation is very low at only 1.3 watts with power supply voltages of +5.0 and -5.2 volts. The SPT7810 also provides a wide input voltage swing of ±2.0 volts.

The SPT7810 is available in a 28-lead ceramic sidebrazed DIP, PDIP, and die form. Commercial and industrial temperature ranges are currently offered. Contact the factory for availability of military temperature range and /883 processed units.

Analog

Input

Coarse

A/D

Analog

Prescaler

T/H Amplifier

Bank

Successive Interpolation

Stage i

Successive Interpolation

Stage i+1

Successive Interpolation

Stage N

Decoding Network

Signal Processing Technologies, Inc.

4755 Forge Road, Colorado Springs, Colorado 80907, USA

Phone: (719) 528-2300 FAX: (719) 528-2370

Digital

Output

ABSOLUTE MAXIMUM RATINGS (Beyond which damage may occur)1 25 °C

Supply Voltages

VCC............................................................... -0.3 to +6 V

Output

Digital Outputs .......................................... +30 to -30 mA

VEE............................................................... +0.3 to -6 V

Temperature

Input Voltages

Analog Input............................................... VFB≤VIN≤V

VFT, VFB. ................................................... +3.0 V, -3.0 V

Reference Ladder Current .....................................12 mA

Operating Temperature ..............................-25 to +85 °C

(1)

Junction Temperature

..............................................

175 °C

Lead Temperature, (soldering 10 seconds).......... 300 °C

Storage Temperature................................-65 to +150 °C

Note: 1. Operation at any Absolute Maximum Rating is not implied. See Electrical Specifications for proper nominal

applied conditions in typical applications.

ELECTRICAL SPECIFICATIONS

TA=T

PARAMETERS CONDITIONS LEVEL MIN TYP MAX MIN TYP MAX UNITS

Resolution 10 10 Bits DC Accuracy (+25 °C) ± Full Scale

- T

min

Integral Nonlinearity 250 kHz Sample Rate V ±1.0 ±1.5 LSB Differential Nonlinearity V ±0.5 ±0.75 LSB No Missing Codes VI Guaranteed Guaranteed

, VCC=+5.0 V, VEE=-5.2 V, VIN=±2.0 V, VSB=-2.0 V, VST=+2.0 V, f

max

TEST TEST SPT7810A SPT7810B

=20 MHz, 50% clock duty cycle, unless otherwise specified.

clock

Analog Input

Input Voltage Range VI ±2.0 ±2.0 V Input Bias Current VIN=0 V VI 30 60 30 60 µA Input Resistance VI 100 300 100 300 kΩ Input Capacitance V 5 5 pF Input Bandwidth 3 dB Small Signal V 120 120 MHz +FS Error V ±2.0 ±2.0 LSB

-FS Error V ±2.0 ±2.0 LSB

Reference Input

Reference Ladder Resistance VI 500 800 500 800 Ω Reference Ladder Tempco V 0.8 0.8 Ω/°C

Timing Characteristics

Maximum Conversion Rate VI 20 20 MHz Overvoltage Recovery Time V 20 20 ns Pipeline Delay (Latency) IV 1 1 Output Delay TA=+25 °CV5 5ns Aperture Delay Time TA=+25 °CV1 1ns Aperture Jitter Time TA=+25 °C V 5 5 ps-RMS

Dynamic Performance

Effective Number of Bits f

=1 MHz 9.2 8.7 Bits

=3.58 MHz 8.8 8.3 Bits

fIN=10.3 MHz 7.5 7.0 Bits

Typical thermal impedances: 28L sidebrazed DIP. θja = 50 °C/W,

28L plastic DIP θja = 50 °C/W.

Clock Cycle

SPT

SPT7810

2 3/11/97

ELECTRICAL SPECIFICATIONS

TA=T

PARAMETERS CONDITIONS LEVEL MIN TYP MAX MIN TYP MAX UNITS

Dynamic Performance

- T

min

Signal-To-Noise Ratio (without Harmonics)

Harmonic Distortion

Signal-to-Noise and Distortion

Spurious Free Dynamic Range +25 °C, f Differential Phase +25 °C, fIN=3.58 & 4.35 MHz V 0.2 0.2 Degree Differential Gain +25 °C, fIN=3.58 & 4.35 MHz V 0.5 0.7 %

, VCC=+5.0 V, VEE=-5.2 V, VIN=±2.0 V, VSB=-2.0 V, VST=+2.0 V, f

max

TEST TEST SPT7810A SPT7810B

=1 MHz +25 °C I 57 60 54 57 dB

fIN=3.58 MHz +25 °C I 56 58 53 55 dB fIN=10.3 MHz +25 °C I 50 53 47 49 dB

fIN=1 MHz +25 °C I 57 60 54 57 dB fIN=3.58 MHz +25 °C I 56 58 53 55 dB fIN=10.3 MHz +25 °C I 46 48 43 45 dB

fIN=1 MHz +25 °C I 55 57 52 54 dB fIN=3.58 MHz +25 °C I 54 55 51 52 dB fIN=10.3 MHz +25 °C I 44 47 41 44 dB

=1 MHz V 67 67 dB

IV 55 58 52 55 dB IV 54 56 51 53 dB IV 47 50 44 46 dB

IV 54 57 51 54 dB IV 53 55 50 52 dB IV 45 47 42 44 dB

IV 52 49 dB IV 51 48 dB IV 43 40 dB

=20 MHz, 50% clock duty cycle, unless otherwise specified.

CLK

Digital Inputs

Logic 1 Voltage VI -1.1 -1.1 V Logic 0 Voltage VI -1.5 -1.5 V Maximum Input Current Low VI -500 ±200 +750 -500 ±200 +750 µA Maximum Input Current High VI -500 ±300 +750 -500 +300 +750 µA Pulse Width Low (CLK) IV 20 20 ns Pulse Width High (CLK) IV 20 300 20 300 ns

Digital Outputs

Logic 1 Voltage 50 Ω to -2 V VI -1.1 -0.8 -1.1 -0.8 V Logic 0 Voltage 50 Ω to -2 V VI -1.8 -1.5 -1.8 -1.5 V

Power Supply Requirements

Voltages V Currents I Power Dissipation Outputs Open VI 1.3 1.6 1.3 1.8 W

Power Supply Rejection Ratio (5 V ±0.25 V, -5.2 V ±2.0 V) V 1.0 1.0 LSB

-V

-I

IV +4.75 -5.0 +5.25 +4.75 +5.0 +5.25 V IV -4.95 -5.2 -5.45 -4.95 -5.2 -5.45 V VI 140 170 140 190 mA VI 115 140 115 160 mA

SPT

SPT7810

3 3/11/97

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