FEATURES
• Monolithic 10 MSPS converter
• 100 mW power dissipation
• On-chip track-and-hold
• Single +5 V power supply
• TTL/CMOS outputs
• 5 pF input capacitance
• Low cost
• Tri-state output buffers
• High ESD protection: 3,500 V minimum
• Selectable +3 V or +5 V logic I/O
SPT7840
10-BIT, 10 MSPS, 100 mW A/D CONVERTER
TECHNICAL DATA
JUNE 27, 2001
APPLICATIONS
• All high-speed applications where low power
dissipation is required
• Video imaging
• Medical imaging
• IR imaging
• Scanners
• Digital communications
GENERAL DESCRIPTION
The SPT7840 is a 10-bit monolithic, low-cost, ultralow-
power analog-to-digital converter capable of minimum
word rates of 10 MSPS. The on-chip track-and-hold func-
tion assures very good dynamic performance without the
need for external components. The input drive require-
ments are minimized due to the SPT7840’s low input
capacitance of only 5 pF.
Power dissipation is extremely low at only 100 mW typical
(120 mW maximum) at 10 MSPS with a power supply of
+5.0 V. The digital outputs are +3 V or +5 V, and are user
selectable. The SPT7840 is pin-compatible with the entire
family of SPT 10-bit, CMOS converters (SPT7835/40/50/
55/60/61), which simplifies upgrades. The SPT7840 has
incorporated proprietary circuit design* and CMOS pro-
cessing technologies to achieve its advanced perfor-
mance. Inputs and outputs are TTL/CMOS-compatible to
interface with TTL/CMOS logic systems. Output data for-
mat is straight binary.
The SPT7840 is available in a 28-lead SOIC package over
the industrial temperature range, and a 32-lead small
(7 mm square) TQFP package over the commercial
temperature range.
BLOCK DIAGRAM
*Patent pending
ADC Section 1
AIN
1:8
Mux
T/H
Auto-
Zero
CMP
CLK In
Enable
Data
Valid
P1
...P2
Timing
and P7
Control
P8
... ADC Section 2
ADC Section 7
ADC Section 8
T/H
Auto-
Zero
CMP
11-Bit
11
SAR
11
DAC
D10 Overrange
D9 (MSB)
D8
D7
...
... 11
11
11-Bit
8:1
D6
Mux/
D5
Error
Correction
11
D4
11-Bit
SAR
D3
11
DAC
D2
D1
Ref
In
Reference Ladder
VREF
D0 (LSB)
Signal Processing Technologies, Inc.
4755 Forge Road, Colorado Springs, Colorado 80907, USA
Phone: 719-528-2300 Fax: 719-528-2370 Web Site: http://www.spt.com e-mail: sales@spt.com