MAXIM MAX1011 Technical data

Quick Start

The MAX1011 EV kit is fully assembled and tested.
Follow these steps to verify proper board operation. Do

not turn on the power supplies until all connections
to the EV kit are completed.

1) Connect a +5V power supply to the pad marked
VCC. Connect this supply’s ground to the pad
marked GND.

2) Connect a +3.3V power supply to the pad labeled
VCCO. Connect the supply ground to the pad
marked OGND.

3) Connect a +3.7V power supply to the pad marked
VTUNE. Connect the supply ground to the GND
pad.

4) Remove the shunt from jumper JU5. This sets a
250mVp-p full-scale range.

General Description

The MAX1011 evaluation kit (EV kit) simplifies evaluation
of the 90Msps MAX1011 6-bit analog-to-digital converter
(ADC). The kit includes the basic components necessary
to operate the on-chip oscillator as a voltage-controlled
oscillator (VCO). The board can also be easily modified to
accommodate an external clocking source.

Connectors for power supplies, analog inputs, and digital
outputs simplify connections to the device. The PC board
features an optimized layout to ensure the best possible
dynamic performance. The EV kit includes a MAX1011.

Features

♦ 5.85 Effective Number of Bits at 20MHz Analog

Input Frequency

♦ Separate Analog and Digital Power and Ground

Connections with Optimized PC Board Layout

♦ Single-Ended or Differential Analog Input
♦ Square-Pin Header for Easy Connection of Logic

Analyzer to Digital Outputs

♦ User-Selectable ADC Full-Scale Gain Ranges
♦ Fully Assembled and Tested Surface-Mount

Board

Evaluates: MAX1011

MAX1011 Evaluation Kit

________________________________________________________________

Maxim Integrated Products

1

SUPPLIER* PHONE FAX

AVX [phone] [phone]

Component Suppliers

Component List

Ordering Information

For free samples & the latest literature: http://www.maxim-ic.com, or phone [phone]
For small orders, phone [phone] ext. 3468.

Coilcraft [phone] [phone]
M/A-COM [phone] [phone]
Sprague [phone] [phone]

*

Please indicate that you are using the MAX1011 when con­tacting these component suppliers.

PART

MAX1011EVKIT 0°C to +70°C

TEMP. RANGE IC PACKAGE

24 QSOP

DESIGNATION QTY DESCRIPTION

C1, C3,

C5

3

0.01µF, 10V min, 10% ceramic
capacitors

C2, C7,

C8

3 47pF, 10V min, 5% ceramic capacitors

C4 1

0.22µF, 10V min, 10% ceramic
capacitor

C6 1 5pF, 10V min, 10% ceramic capacitor

C9, C10 2

0.1µF, 10V min, 10% ceramic
capacitors

D1 1

Varactor diode
M/A-COM MA4ST079CK-287, SOT23

JU1, JU2, JU6 3 0Ω resistors

JU3, JU4 2 2-pin headers

JU5 1 3-pin header

C11, C12 2

10µF, 10V min, 20% tantalum caps
AVX TAJC106K016

J1 1 14-pin connector

R2, R3 2 47kΩ, 5% resistors
R4, R5 2 49.9Ω, 1% resistors

None 1

MAX1011CEG

IN+, IN- 2 BNC connectors

Clock

Overdrive

0 Not Supplied

MAX1011 circuit board

None 1 Shunt for JU5

U1 1

R1 1 10kΩ, 5% resistor

L1 1

220nH inductor
Coilcraft 1008CS-221XKB

19-1335; Rev 0a; 2/98

查询MAX1011EVKIT供应商

Evaluates: MAX1011

5) Connect a 250mVp-p, 20MHz sine-wave source to
the analog input at BNC J3. The analog input is ter­minated in 50Ω (R4).

6) Connect a logic analyzer to connector J1 to monitor
the digital outputs.

7) Turn on all power supplies and signal sources.

8) Observe the digitized analog input signals with the
logic analyzer.

_______________Detailed Description

EV Kit Jumpers

The MAX1011 EV kit contains several jumpers that con­trol board and part options. The following sections
describe the different jumpers and their purposes.
Table 1 lists the jumpers on the EV kit and their default
positions.

Analog Supply Power Requirements

The MAX1011 requires a +5V at approximately 37mA for
the analog VCCsupply. 0Ω resistors are installed at
jumper sites JU1, JU2, and JU6 and can be removed to
sense device power-supply currents with an ammeter.

Digital Outputs Supply

The MAX1011 requires +3.3V for the V

CCO

supply. The
current requirement from the power supply is a function
of the sampling clock and analog input frequencies, as
well as the capacitive loading on the digital outputs.
With 15pF loads and a 20MHz analog input frequency
sampled at 90Msps, the current draw is approximately

8.5mA.

Analog Inputs

The analog inputs to the ADC are provided through
BNC connectors IN+, and IN-. The connectors are ter­minated with 49.9Ω to ground and are AC coupled to
the converter’s analog inputs, which are internally self­biased at 2.35V DC. A typical application circuit drives
the IN+ noninverting analog input using AC-coupled
signals. The nominal 20kΩ input resistance of the ana-

log inputs, plus the 0.1µF AC-coupling capacitor value,
sets the low-frequency corner at approximately 80Hz.

You can drive the analog inputs either single-ended or
differentially using AC- or DC-coupled inputs. Either the
inverting or the noninverting input can be driven single­ended. If the inverting input is driven, then the digital
output codes are inverted (complemented). Refer to the
MAX1011 data sheet for typical circuits.

ADC Gain Selection

The single GAIN-select pin on the MAX1011 controls
the full-scale input range. Jumper JU5 is used to manu­ally select the desired gain range as shown in Table 2.
The EV kits are shipped with the mid-gain range select­ed (jumper pins open).

Table 3 lists the possible input-drive combinations
for the mid-gain (250mVp-p) full-scale range selection.
Drive levels are referenced to the open-circuit,
common-mode voltage of the analog inputs (typically

MAX1011 Evaluation Kit

2 _______________________________________________________________________________________

Open

Offset-correction
amplifier enabled

JU3, JU4

Shorted with 0Ω

resistors

Power-supply current­sense ports

JU1, JU2,

JU6

DEFAULT
POSITION

FUNCTIONJUMPER(S)

Open

ADC full-scale range
selection

JU5

Mid-gain, 250mVp-p

OPEN

Low-gain, 500mVp-pGND

ADC GAIN RANGE

MAX1011 GAIN

CONTROL PIN

JU5 SETTING

High-gain, 125mVp-pV

CC

INPUT DRIVE

Single-Ended

Noninverting

0

+125mV

IN+

-125mV

Open Circuit

Open Circuit

IN-

Open Circuit

100000

111111

OUTPUT

CODE

000000

Open Circuit

Open Circuit

Open Circuit

0

+125mV

-125mV

Single-Ended

Inverting

011111

000000

111111

0

+62.5mV

-62.5mV

0

-62.5mV

+62.5mV

Differential

100000

111111

000000

JU5

1
2
3

JU5

1
2
3

JU5

1
2
3

Table 1. EV Kit Jumpers and Default
Positions

Table 2. Gain-Selection Jumper JU5
Settings

Table 3. Typical Input-Drive Requirements
for Mid-Gain

Evaluates: MAX1011

MAX1011 Evaluation Kit

_______________________________________________________________________________________ 3

2.35V) if DC coupled, or to ground if AC coupling is
used. If the low-gain (500mVp-p) range is selected, the
input-drive requirements are twice those listed in Table

3. If the high-gain (125mVp-p) range is selected, the
input-drive requirements are half those listed in Table 3.

Offset-Correction Amplifier

The offset-correction amplifier included on the
MAX1011 is usually enabled in a typical AC-coupled
application circuit. For DC-coupled applications, the
amplifier must be disabled by installing shorting blocks
on jumpers JU3 and JU4. These jumpers short device
pins OCC+ (pin 2) and OCC- (pin 3) to ground and dis­able the amplifier. The MAX1011 EV kit is configured
with the offset-correction amplifier enabled (jumpers
open) and AC-coupled analog inputs.

Voltage-Controlled-Oscillator Operation

The EV kit includes a voltage-controlled-oscillator
(VCO) circuit to set the analog-to-digital converter
(ADC) sampling rate using an external resonant tank
and a varactor diode. A voltage applied to the VTUNE
pad changes the varactor diode’s capacitance to
adjust the tank’s resonant frequency, which sets the
oscillator’s sampling frequency. VTUNE voltage can be
varied from 0V to a maximum of 8V.

The EV kit is designed so that a nominal VTUNE control
voltage of about 3.7V sets the ADC sampling rate to
90Msps. The VTUNE control voltage should be well fil­tered, as any noise on the supply contributes to jitter in
the internal oscillator and degrades the converter’s
dynamic performance. Figure 1 shows the VTUNE
control-voltage typical frequency-adjustment range for
the MAX1011 EV kit (for VCO mode, refer to schematic
in Figure 2).

External Clock Operation

The MAX1011 EV kit can be converted to drive the ADC
from an external clock source. This involves removing
the external resonator components from the VCO circuit
and adding a few new components. Table 4 lists the EV
kit changes required to convert the board to accept an
external clock source. The resulting schematic is
shown in Figure 3.

The new 49.9Ω value of R3 shown in Figure 3 provides
proper termination for a 50Ω external signal generator.
AC-coupling capacitor C7 couples the external clock
signal to the MAX1011 oscillator circuitry at TNK+ (pin

7). R2 and C8 ensure that the impedance at both ports
of the oscillator is balanced. After all modifications are
complete, connect an external clock source to the BNC
connector on the EV kit marked CLOCK OVERDRIVE
(J2). The recommended clock amplitude is 1Vp-p; how­ever, the ADC operates correctly with as little as
300mVp-p or up to 1.25Vp-p on CLOCK OVERDRIVE.

The external clock source should have low-phase noise
for best dynamic performance. A low-phase-noise
sine-wave oscillator serves this purpose well. A square­wave clock source is not necessary to drive the
MAX1011. The device contains sufficient gain to ampli­fy even a low-level-input sine wave to drive the ADC
comparators, while ensuring excellent dynamic perfor­mance.

60

70
65

80
75

90
85

95

105
100

110

0 2 31 4 5 6 7 8

MAX1011 Fig01

VTUNE CONTROL VOLTAGE (V)

FREQUENCY (MHz)

Figure 1. MAX1011 Oscillator Frequency vs. VTUNE Control
Voltage

D1 RemoveVaractor diode

R1

R2, R3

L1

Replace with

49.9Ω resistors

47kΩ resistors

Remove
Remove

220nH inductor
10kΩ resistor

Replace with

0.01µF capaci­tors

MODIFICATION

Add
Remove

C6

C7, C8

Clock Overdrive

(J2)

COMPONENT

47pF capacitors

DESCRIPTION

Clock input BNC
connector

5pF capacitor

Table 4. External Clock Source EV Kit
Modifications