MAXIM MAX5404EUB

19-1934; Rev 1; 4/01
Dual 256-Tap, Low-Drift,
Digital Potentiometers in 10-µMAX
Features
♦ 10-Pin µMAX Small Footprint Package
♦ 256-Tap Positions
♦ Ultra Low 0.1µA Supply Current
♦ +2.7V to +5.5V Single-Supply Operation
♦ Low End-To-End Temperature Coefficient:
35ppm/°C
♦ Low Ratiometric Temperature Coefficient:
5ppm/°C
♦ Power-On Reset: Wiper Goes to Midscale
(Position 128)
♦ Glitchless Switching Between Resistor Taps
♦ 3-Wire SPI™ -Interface Compatible
♦ 10kΩ/50kΩ/100kΩ Resistor Values
Applications
Mechanical Potentiometer Replacement
Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
R (kΩ)
Low-Drift Programmable Gain Amplifier (PGA)
MAX5403EUB
-40°C to +85°C
10 µMAX
Volume Control
MAX5404EUB
-40°C to +85°C
10 µMAX
50
LCD Screen Adjustment
MAX5405EUB
-40°C to +85°C
10 µMAX
100
10
Adjustable Voltage Reference
Programmable Filters, Delays, Time Constant
Impedance Matching
Pin Configuration
TOP VIEW
GND 1
SPI is a registered trademark of Motorola, Inc.
LB
2
HB
3
WB
4
CS
5
10 LA
MAX5403
MAX5404
MAX5405
9
WA
8
VDD
7
SCLK
6
DIN
µMAX
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
1
MAX5403/MAX5404/MAX5405
General Description
The MAX5403/MAX5404/MAX5405 is a family of dual
linear taper digital potentiometers. Each device has one
3-terminal potentiometer and one 2-terminal variable
resistor (Figure 1). The MAX5403/MAX5404/MAX5405
operate from +2.7V to +5.5V single-supply voltages
and use an ultra-low supply current of 0.1µA. These
devices also provide glitchless switching between
resistors taps as well as a convenient power-on reset
(POR) that sets the wiper to the midscale position at
power-up. The potentiometer consists of a fixed resistor
with a wiper contact that is digitally controlled through a
3-wire serial interface and has 256-tap points. It performs the same function as a discrete potentiometer or
variable resistor.
These parts are ideal for applications requiring digitally
controlled resistors. Three resistance values are available: 10kΩ (MAX5403), 50kΩ (MAX5404), and 100kΩ
(MAX5405). A nominal resistor-temperature coefficient
of 35ppm/°C end-to-end and 5ppm/°C ratiometric make
the MAX5403/MAX5404/MAX5405 ideal for applications
requiring low temperature-coefficient variable resistors,
such as adjustable-gain circuit configurations.
The MAX5403/MAX5404/MAX5405 are available in a 10pin µMAX package. Each device is guaranteed over the
extended industrial temperature range (-40°C to +85°C).
MAX5403/MAX5404/MAX5405
Dual 256-Tap, Low-Drift,
Digital Potentiometers in 10-µMAX
ABSOLUTE MAXIMUM RATINGS
VDD to GND ..............................................................-0.3V to +6V
DIN, SCLK, CS .........................................................-0.3V to +6V
HX, LX, WX to GND .......................................-0.3V to (VDD + 0.3)
Maximum Continuous Current Into HX, LX, and WX ...........±1mA
Continuous Power Dissipation (TA = +70°C)
10-Pin µMAX (derate 5.6mW/°C above +70°C) ...........444mW
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(VDD = +5V, unless otherwise noted. VH = VDD, VL = 0, TA = TMIN to TMAX. Typical values are at VDD = +5V, TA = +25°C,
unless otherwise noted.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
±1/2
LSB
DC PERFORMANCE (Voltage Divider Mode)
Resolution
N
Integral Nonlinearity (Notes 1, 2)
INL
Differential Nonlinearity (Notes 1, 2)
DNL
End-to-End Resistor Tempco
TCR
8
Bits
±1/2
Ratiometric Resistor Tempco
LSB
35
ppm/°C
5
ppm/°C
Full-Scale Error
MAX5403
-8
LSB
Zero-Scale Error
MAX5403
+8
LSB
Full-Scale Error
MAX5404
-1.6
LSB
Zero-Scale Error
MAX5404
+1.6
LSB
Full-Scale Error
MAX5405
-0.8
LSB
Zero-Scale Error
MAX5405
+0.8
LSB
DC PERFORMANCE (Variable Resistor Mode)
Resolution
N
8
VDD = +5V
Integral Nonlinearity (Notes 1, 3)
DNL
±2.5
MAX5403 (Pot B)
±1
MAX5404
±1
±1
MAX5405
INL
VDD = +3V
Differential Nonlinearity
(Notes 1, 3)
Bits
MAX5403 (Pot A)
MAX5403 (Pot A)
±4.5
MAX5403 (Pot B)
±3
MAX5404
±1.5
MAX5405
±1.5
VDD = +5V
±1/2
VDD = +3V
LSB
LSB
DC PERFORMANCE (Resistor Characteristics)
Wiper Resistance (Note 4)
RW
Wiper Capacitance
CW
2
VDD = +5V
275
VDD = +3V
550
MAX5403
50
MAX5404/MAX5405
30
_______________________________________________________________________________________
Ω
pF
Dual 256-Tap, Low-Drift,
Digital Potentiometers in 10-µMAX
(VDD = +5V, unless otherwise noted. VH = VDD, VL = 0, TA = TMIN to TMAX. Typical values are at VDD = +5V, TA = +25°C,
unless otherwise noted.)
PARAMETER
End-to-End Resistance
SYMBOL
RHL
CONDITIONS
MIN
TYP
MAX
MAX5403
7.5
10
12.5
MAX5404
37.5
50
62.5
MAX5405
75
100
125
UNITS
kΩ
DIGITAL INPUTS
Input High Voltage
VIH
Input Low Voltage
VIL
0.7 ✕ VDD
V
Input Leakage Current
Input Capacitance
0.3 ✕ VDD
V
±1.0
µA
5
pF
TIMING CHARACTERISTICS (ANALOG)
Wiper-Settling Time
tS
MAX5403
100
MAX5404
325
MAX5405
650
ns
TIMING CHARACTERISTICS (DIGITAL) (Note 5)
Maximum SCLK Frequency
10
MHz
SCLK Clock Period
tCP
100
ns
SCLK Pulse Width High
tCH
40
ns
SCLK Pulse Width Low
tCL
40
ns
CS Fall to SCLK Rise Setup Time
tCSS
40
ns
SCLK Rise to CS Rise Hold Time
tCSH
0
ns
tDS
40
ns
DIN Setup Time
DIN Hold Time
tDH
0
ns
SCLK Rise to CS Fall Delay
tCS0
10
ns
CS Rise to SCLK Rise Hold
tCS1
40
ns
CS Pulse Width High
tCSW
100
ns
POWER SUPPLIES
Supply Voltage
Supply Current
VDD
IDD
2.7
CS = SCLK = DIN = VDD
VDD = +5V
0.8
VDD = +2.7V
0.1
5.5
V
5
µA
µA
Note 1: Linearity is defined in terms of the HX to LX code-dependent resistance.
Note 2: The DNL and INL are measured with the potentiometer configured as a voltage divider with HX = VDD and LX = 0. The wiper
terminal is unloaded and measured with an ideal voltmeter.
Note 3: The DNL and INL are measured with the potentiometer configured as a variable resistor. For the 3-terminal potentiometer
(Pot A), HA is unconnected and LA = 0. For the 2-terminal potentiometer (Pot B), only LB = 0. At VDD = +5V, the wiper terminal is driven with a source current of 400µA for the 10kΩ configuration, 80µA for the 50kΩ configuration, and 40µA for the
100kΩ configuration. At VDD = +3V, 200µA/40µA/20µA for 10kΩ/50kΩ/100kΩ configuration respectively.
Note 4: The wiper resistance is the worst value measured by injecting into WX, a current IW = VDD / RHL.
Note 5: Digital timing is guaranteed by design.
_______________________________________________________________________________________
3
MAX5403/MAX5404/MAX5405
ELECTRICAL CHARACTERISTICS (continued)
Typical Operating Characteristics
(VDD = +5.0V, TA = +25°C, unless otherwise noted.)
WIPER RESISTANCE vs.
WIPER VOLTAGE (100kΩ)
280
VDD = +5V
260
240
220
180
280
260
240
180
160
WIPER VOLTAGE (V)
WIPER-TO-END RESISTANCE
vs. INPUT CODE (50kΩ)
WIPER-TO-END RESISTANCE
vs. INPUT CODE (100kΩ)
100
MAX5403 toc04
90
35
30
25
20
15
0
WIPER-TO-END RESISTANCE
vs. INPUT CODE (10kΩ)
10
9
70
60
50
40
30
8
7
6
5
4
3
10
20
2
5
10
1
0
0
64
96
0
0
128 160 192 224 256
32
64
96
INPUT CODE (DECIMAL)
INPUT CODE (DECIMAL)
VARIABLE RESISTOR DNL
vs. INPUT CODE (10kΩ)
VARIABLE RESISTOR INL
vs. INPUT CODE (10kΩ)
0.50
MAX5403 toc07
0.20
0.40
INL (LSB)
0.15
0.10
0.05
0.20
0.03
0.10
128 160 192 224 256
INPUT CODE (DECIMAL)
0.02
0.01
0.00
VDD = +5V
-0.01
-0.02
-0.30
96
128 160 192 224 256
0.05
0.04
-0.20
64
96
0.06
0.30
0.00
32
64
VARIABLE RESISTOR DNL
vs. INPUT CODE (50kΩ)
-0.10
0
32
INPUT CODE (DECIMAL)
0.00
-0.05
0
128 160 192 224 256
DNL (LSB)
32
MAX5403 toc08
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
WIPER VOLTAGE (V)
W-TO-L RESISTANCE (kΩ)
80
W-TO-L RESISTANCE (kΩ)
40
VDD = +5V
200
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
WIPER VOLTAGE (V)
45
MAX5403 toc03
220
VDD = +5V
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
50
4
240
MAX5403 toc05
0
VDD = +3V
260
180
160
160
W-TO-L RESISTANCE (kΩ)
320
300
220
200
200
280
MAX5403 toc06
300
VDD = +3V
MAX5403 toc09
VDD = +3V
320
360
340
300
WIPER RESISTANCE (Ω)
340
WIPER RESISTANCE (Ω)
360
WIPER RESISTANCE (Ω)
400
380
MAX5403 toc01
380
WIPER-TO-END RESISTANCE
vs. WIPER VOLTAGE (10kΩ)
MAX5403 toc02
WIPER RESISTANCE vs.
WIPER VOLTAGE (50kΩ)
DNL (LSB)
MAX5403/MAX5404/MAX5405
Dual 256-Tap, Low-Drift,
Digital Potentiometers in 10-µMAX
-0.03
0
32
64
96
128 160 192 224 256
INPUT CODE (DECIMAL)
0
32
64
96
128 160 192 224 256
INPUT CODE (DECIMAL)
_______________________________________________________________________________________
Dual 256-Tap, Low-Drift,
Digital Potentiometers in 10-µMAX
VARIABLE RESISTOR INL
vs. INPUT CODE (50kΩ)
-0.04
-0.06
-0.08
-0.10
-0.12
-0.14
-0.16
32
64
96
0.05
0.04
0.03
0.02
0.01
0.00
-0.01
-0.02
128 160 192 224 256
32
64
96
128
160 192 224
VOLTAGE-DIVIDER INL
vs. INPUT CODE (10kΩ)
MAX5403 toc13
0.15
0.10
0
256
0.03
0.02
0.01
64
96
128
160 192 224
0.00
-0.05
256
0.02
0.00
-0.02
0
32
64
96
128
160 192 224
0
256
32
VOLTAGE-DIVIDER DNL
vs. INPUT CODE (100kΩ)
0.07
0.06
0.03
0.02
0.00
-0.05
-0.10
0.00
-0.15
256
0.05
0.04
0.01
-0.10
160 192 224
0.10
INL (LSB)
DNL (LSB)
-0.05
128
0.15
0.05
0.00
96
VOLTAGE-DIVIDER INL
vs. INPUT CODE (100kΩ)
MAX5403 toc17
MAX5403 toc16
0.08
64
INPUT CODE (DECIMAL)
INPUT CODE (DECIMAL)
0.05
INL (LSB)
0.03
-0.01
VOLTAGE-DIVIDER INL
vs. INPUT CODE (50kΩ)
0.10
0.04
0.01
INPUT CODE (DECIMAL)
0.15
256
0.05
-0.20
32
160 192 224
0.06
-0.01
0
128
0.07
-0.15
-0.02
96
0.08
-0.10
0.00
64
VOLTAGE-DIVIDER DNL
vs. INPUT CODE (50kΩ)
DNL (LSB)
INL (LSB)
0.04
32
INPUT CODE (DECIMAL)
0.05
0.05
MAX5403 toc12
-0.20
0
VOLTAGE-DIVIDER DNL
vs. INPUT CODE (10kΩ)
0.06
-0.05
-0.15
INPUT CODE (DECIMAL)
0.07
0.00
-0.10
INPUT CODE (DECIMAL)
0.08
DNL (LSB)
0.05
MAX5403 toc14
0
0.10
MAX5403 toc15
DNL (LSB)
INL (LSB)
-0.02
0.15
MAX5403 toc18
0.00
0.11
0.10
0.09
0.08
0.07
0.06
INL (LSB)
0.02
VARIABLE RESISTOR INL
vs. INPUT CODE (100kΩ)
MAX5403 toc11
0.12
MAX5403 toc10
0.04
VARIABLE RESISTOR DNL
vs. INPUT CODE (100kΩ)
-0.15
-0.01
-0.20
-0.20
-0.02
0
32
64
96
128
160 192 224
INPUT CODE (DECIMAL)
256
0
32
64
96
128
160 192 224
INPUT CODE (DECIMAL)
256
0
32
64
96
128
160 192 224
256
INPUT CODE (DECIMAL)
_______________________________________________________________________________________
5
MAX5403/MAX5404/MAX5405
Typical Operating Characteristics (continued)
(VDD = +5.0V, TA = +25°C, unless otherwise noted.)
Typical Operating Characteristics (continued)
(VDD = +5.0V, TA = +25°C, unless otherwise noted.)
SUPPLY CURRENT
vs. LOGIC INPUT VOLTAGE
SUPPLY CURRENT vs. TEMPERATURE
VDD = +5V
0.1
0.01
VDD = +3V
MAX5403 toc20
VDD = +5V
0.8
SUPPLY CURRENT (µA)
1
SUPPLY CURRENT (mA)
1.0
MAX5403 toc19
10
0.6
0.4
VDD = +3V
0.2
0.001
0.0001
0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
0
-40 -30 -20 -10 0 10 20 30 40 50 60 70 80
INPUT LOGIC VOLTAGE (V)
TEMPERATURE (°C)
END-TO-END RESISTANCE % CHANGE
vs. TEMPERATURE
TAP-TO-TAP SWITCHING TRANSIENT
(CODE 127 TO 128)
10kΩ
0.15
50kΩ
0.10
0.05
MAX5403 toc22
MAX5403 toc21
0.20
END-TO-END RESISTANCE % CHANGE
MAX5403/MAX5404/MAX5405
Dual 256-Tap, Low-Drift,
Digital Potentiometers in 10-µMAX
100kΩ
0
VW-L
10mV/div
50kΩ
-0.05
100kΩ
-0.10
-0.15
-0.20
CS
5V/div
10kΩ
-0.25
-40
-20
0
20
40
60
80
200ns/div
TEMPERATURE (°C)
6
_______________________________________________________________________________________
Dual 256-Tap, Low-Drift,
Digital Potentiometers in 10-µMAX
PIN
NAME
FUNCTION
1
GND
2
LB
Low Terminal of Resistor B
3
HB
High Terminal of Resistor B
4
WB
Wiper Terminal of Resistor B
5
CS
SPI Chip Select
6
DIN
SPI Serial Data Input
7
SCLK
8
VDD
Power Supply, +2.7V to +5.5V. Connect a 0.1µF capacitor to GND.
9
WA
Wiper Terminal of Resistor A
10
LA
Low Terminal of Resistor A
Ground
SPI Clock Input
POR
MAX5403
MAX5404
MAX5405
VDD
GND
R
DIN
9-BIT
SHIFT
REGISTER
8
R
8-BIT
LATCH
WA
8
256
DECODE
LA
HB
R
8-BIT
LATCH
SCLK
CS
8
256
DECODE
WB
LB
SR
DECODE
Figure 1. MAX5403/MAX5404/MAX5405 Functional Diagram: 2-Terminal Variable Resistor and 3-Terminal Potentiometers in 10-µMAX
Configuration
Detailed Description
Each potentiometer consists of 255 fixed resistors in
series between pins H B and L B for the 3-terminal
potentiometer and between WA and LA for the 2-terminal variable resistor (Figure 1). The potentiometer wiper
(pin WX) can be programmed to access any one of the
256 different tap points on the resistor string. The
MAX5403/MAX5404/MAX5405 require nine bits to program the wiper position. The 1st bit is an address code,
allowing one or the other potentiometers to be selected
for programming. The potentiometers are programmed
independently of each other.
The MAX5403/MAX5404/MAX5405 use a 3-wire serial
data interface to control the wiper tap position. This
write-only interface contains three inputs: Chip Select
(CS), Data In (DIN), and Data Clock (SCLK). When CS
is taken low, data from the DIN pin is synchronously
loaded into the serial shift register on each rising edge
_______________________________________________________________________________________
7
MAX5403/MAX5404/MAX5405
Pin Description
MAX5403/MAX5404/MAX5405
Dual 256-Tap, Low-Drift,
Digital Potentiometers in 10-µMAX
POT REGISTER LOADED
CS
SCLK
1ST CLOCK PULSE
DIN
A0
D7
9TH CLOCK PULSE
D6
D5
D4
MSB
D3
D2
D1
D0
LSB
TIME
Figure 2. Potentiometer Serial Data Timing Circuit
CS
•••
tCSO
tCSS
tCL
SCLK
tCSW
tCS1
tCH
tCP
tCSH
•••
tDS
tDH
•••
DIN
Figure 3. Detailed Serial Interface Timing Diagram
of each SCLK pulse (Figure 2). After all the data bits
have been shifted in, they are latched into the appropriate potentiometer control register when CS transitions
from low to high. Note that if CS is not kept low during
the entire data stream, the data will be corrupted and
the device will need to be reloaded.
The first bit A0 (address bit) is used to address one or
the other of the potentiometers for programming.
Potentiometer control register A is selected for writing
when A0 is ‘zero’, and potentiometer control register B
is selected when A0 is one.
The MAX5403/MAX5404/MAX5405 feature POR circuitry
that sets the wiper to the midscale position at power-up.
Applications Information
The MAX5403/MAX5404/MAX5405 are intended for a
variety of circuits where accurate, fine-tuning adjustable
resistance is required, such as in adjustable voltage or
adjustable gain circuit configurations. It is primarily used
in either a potentiometer divider or a variable resistor
configuration.
8
Adjustable Current to Voltage Converter
Figure 5 shows the MAX5403/MAX5404/MAX5405 being
used with a MAX4250 low-noise op amp to fine tune a
current to voltage converter. Pins HB and WB of the
MAX5403/MAX5404/MAX5405 3-terminal potentiometer
(only pin WA of the 2-terminal variable resistor) are connected to the node between R3 and R2 (pin LX is connected to ground). Circuit space is minimized due to
both devices’ packaging.
Adjustable Gain Amplifier
Figure 6 shows how to use the MAX5403/MAX5404/
MAX5405 to digitally adjust the gain of a noninverting op
amp configuration. In Figure 6a, connect the MAX5403/
MAX5404/MAX5405 as a 2-terminal variable resistor in
series with a resistor to ground to form the adjustable
gain control of a noninverting amplifier.
Similarly, Figure 6b shows how to use the MAX5403/
MAX5404/MAX5405 as a 3-terminal potentiometer. In
this application the MAX5403/MAX5404/MAX5405 low
5ppm/°C ratiometric tempco allows for a very stable
adjustable gain-configuration overtemperature.
_______________________________________________________________________________________
Dual 256-Tap, Low-Drift,
Digital Potentiometers in 10-µMAX
B0 (A0)
DATA WORD
B1 (D7)
B2 (D6)
B3 (D5)
B4 (D4)
B5 (D3)
B6 (D2)
B7 (D1)
B8 (D0)
(MSB)
(LSB)
First Bit In
Last Bit In
Figure 4. Serial Data Format
R3
WA
VCC
VOUT
MAX5403
MAX5404
MAX5405
R1
R2
LA
+5V
WA
V0
MAX5403
MAX5404
MAX5405
MAX4250
LA
V0 / IS = R3 (1 + R2/R1) + R2
Figure 5. I to V Converter
VCC
Figure 6a. Adjustable Gain Circuit Using: 2-Terminal Variable
Resistor
VIN
VOUT
+5V
VIN
OUT
VOREF
WB
HB
VOREF = 12.3kV ✕ Ω / (100kΩ ✕ C / 255) for MAX5403
HB
MAX6160
LB
ADJ
GND
VOREF = 61.5kV ✕ Ω / (50kΩ ✕ C / 255) for MAX5404
WB
VOREF = 123kV ✕ Ω / (100kΩ ✕ C / 255) for MAX5405
WHERE C IS ANY CODE BEING WRITTEN TO A DEVICE.
LB
MAX5403
MAX5404
MAX5405
Figure 6b. Adjustable Gain Circuit Using: 3-Terminal
Potentiometer
Adjustable Voltage Reference
In Figure 7a, the MAX5403/MAX5404/MAX5405 is
shown with the MAX6160 to make an adjustable voltage reference. In this circuit, the H X pin of the
MAX5403/MAX5404/MAX5405 is connected to the OUT
pin of the MAX6160, the L X pin of the MAX5403/
MAX5404/MAX5405 is connected to GND, and the WX
Figure 7a. Adjustable Voltage Reference Using: 3-Terminal
Potentiometer
pin of the MAX5403/MAX5404/MAX5405 is connected
to the ADJ pin of the MAX6160. The MAX5403/
MAX5404/MAX5405 allow precise setting of the voltage
reference output. A low 5ppm/°C ratiometric tempco
allows a very stable, adjustable voltage over temperature.
_______________________________________________________________________________________
9
MAX5403/MAX5404/MAX5405
ADDRESS
Chip Information
TRANSISTOR COUNT: 8689
PROCESS: BiCMOS
Package Information
10LUMAX.EPS
MAX5403/MAX5404/MAX5405
Dual 256-Tap, Low-Drift,
Digital Potentiometers in 10-µMAX
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
10 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2001 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.