SPT7938 Datasheet, PDF (1/10 Pages) Cadeka Microcircuits LLC. – 12-BIT, 40 MSPS, 170 mW A/D CONVERTER

SPT7938
12-BIT, 40 MSPS, 170 mW A/D CONVERTER
FEATURES
• Monolithic 40 MSPS Analog-to-Digital Converter
• 170 mW Power Dissipation
• On-Chip Track-and-Hold
• Single +5 V Power Supply
• TTL/CMOS Outputs
• 20 pF Input Capacitance
• Selectable +3 V or +5 V Logic I/O
APPLICATIONS
• All High-Speed Applications Where
Low Power Dissipation Is Required
• Video Imaging
• Medical Imaging
• Radar Receivers
• IR Imaging
• Digital Communications
GENERAL DESCRIPTION
The SPT7938 is a 12-bit monolithic, low-cost, low-power
analog-to-digital converter capable of minimum word rates
of 40 MSPS. The on-chip track-and-hold function assures
very good dynamic performance without the need for exter-
nal components. The input drive requirements are mini-
mized due to the SPT7938’s low input capacitance of only
20 pF.
Power dissipation is extremely low at only 170 mW typical at
40 MSPS with a power supply of +5.0 V. The digital outputs
are +3 V or +5 V, and are user selectable. The SPT7938 has
incorporated proprietary circuit design and CMOS process-
ing technologies to achieve its advanced performance. In-
puts and outputs are TTL/CMOS compatible to interface
with TTL/CMOS logic systems. Output data format is
straight binary.
The SPT7938 is available in a 28-lead SSOP package over
the industrial temperature range.
BLOCK DIAGRAM
1:18
A_IN
Mux
ADC Section 1
T/H
Auto-
Zero
CMP
CLK In
P1
P2
.
.
Timing .
and ^P17
Control
P18
ADC Se_.ction 2
.
.
ADC Section 17
ADC Section 18
T/H
Auto-
Zero
CMP
13-Bit
13
SAR
13
DAC
D12 Out of Range
D11 (MSB)
D10
D9
13
D8
.
.
.
.
.
.
13-Bit
D7
13
18:1
Mux/
D6
Error
Correction
13
D5
13-Bit
SAR
D4
13
D3
DAC
D2
D1
Reference Ladder
EN
DØ (LSB)
VRHF VRHS
VRLS
VRLF