MAX108 Datasheet, PDF (12/32 Pages) Maxim Integrated Products – ±5V, 1.5Gsps, 8-Bit ADC with On-Chip 2.2GHz Track/Hold Amplifier

±5V, 1.5Gsps, 8-Bit ADC with
On-Chip 2.2GHz Track/Hold Amplifier
BANDGAP
REFERENCE
REF REF
OUT IN
+2.5V
REFERENCE
AMPLIFIER
VOSADJ
GNDI
50Ω
VIN+
VIN-
50Ω
GNDR
BIAS CURRENTS
T/H AMPLIFIER
CLK+
CLKCOM
CLK-
GNDI
50Ω
50Ω
T/H
CLOCK
DRIVER
ADC
CLOCK
DRIVER
MAX108
8-BIT
2
FLASH ADC
16
LOGIC
CLOCK
DRIVER
DIFFERENTIAL
PECL OUTPUTS
OVERRANGE
OR
BIT
2
AUXILIARY
DATA PORT
16
A0–A7
PRIMARY
P0–P7
DATA PORT
16
DATA
READY CLOCK ₂
DREADY
DEMUX
CLOCK
DRIVER
RSTIN+
RSTIN-
RESET
INPUT DUAL LATCH
RESET
PIPELINE
DELAYED
RESET
DEMUX
CLOCK
GENERATOR
DEMUXEN DIVSELECT
DEMUX
RESET OUTPUT ₂
RSTOUT
Figure 1. Simplified Functional Diagram
_______________Detailed Description
The MAX108 is an 8-bit, 1.5Gsps flash analog-to-digital
converter (ADC) with on-chip T/H amplifier and differ-
ential PECL-compatible outputs. The ADC (Figure 1)
employs a fully differential 8-bit quantizer and a unique
encoding scheme to limit metastable states, with no
error exceeding 1LSB max.
An integrated 8:16 output demultiplexer simplifies inter-
facing to the part by reducing the output data rate to
one-half the sampling clock rate. This demultiplexer
has internal reset capability that allows multiple
MAX108s to be time-interleaved to achieve higher
effective sampling rates.
When clocked at 1.5Gsps, the MAX108 provides a typi-
cal ENOB of 7.5 bits at an analog input frequency of
750MHz. The analog input of the MAX108 is designed
for differential or single-ended use with a ±250mV full-
scale input range. In addition, this fast ADC features an
on-chip +2.5V precision bandgap reference. If desired,
an external reference can also be used.
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