General Description
The MAX5395 single, 256-tap volatile, low-voltage
linear taper digital potentiometer offers three end-to-
end resistance values of 10kΩ, 50kΩ, and 100kΩ.
Potentiometer terminals are independent of supply for
voltages up to 5.25V with single-supply operation from
1.7V to 5.5V (charge pump enabled). User-controlled
shutdown modes allow the H, W, or L terminal to be
opened with the wiper position set to zero-code, mid-
code, full-code, or the value contained in the wiper
register. Ultra-low-quiescent supply current (< 1µA) can
be achieved for supply voltages between 2.6V and 5.5V
by disabling the internal charge pump and not allowing
potentiometer terminals to exceed the supply voltage by
more than 0.3V. The MAX5395 provides a low 50ppm/°C
end-to-end temperature coefficient and features an I2C
serial interface.
The small package size, low operating supply voltage,
low supply current, and automotive temperature range
of the MAX5395 make the device uniquely suited for the
portable consumer market and battery-backup industrial
applications.
The MAX5395 is available in a lead-free, 8-pin TDFN
(2mm x 2mm) package. The device operates over the
-40°C to +125°C automotive temperature range.
Benets and Features
Single Linear Taper 256-Tap Positions
10kΩ, 50kΩ, and 100kΩ End-to-End Resistance
1.7V to 5.5V Extended Single Supply
0 to 5.25V H, W, L Operating Voltage Independent of VDD
1μA (typ) Supply Current in Low-Power Mode
±1.0 LSB INL, ±0.5 LSB DNL (max) Wiper Accuracy
Power-On Sets Wiper to Midscale
50ppm/°C End-to-End Temperature Coefficient
5ppm/°C Ratiometric Temperature Coefficient
-40°C to +125°C Operating Temperature Range
2mm x 2mm, 8-Pin TDFN Package
I2C-Compatible Serial Interface
Applications
Portable Electronics
System Calibration
Battery-Powered Systems
Mechanical Potentiometer Replacement
Ordering Information appears at end of data sheet.
19-6393; Rev 3; 2/16
I2C
INTERFACE
1.7V TO 5.5V
(CHARGE PUMP ENABLED) H
W
LR1
VS
VO
+5V
VDD
MAX5395
MAX4250
GND
VO/VS = 1 + RMAX5395/R1
SDA
SCL
ADDR0
MAX5395 Single, 256-Tap Volatile, I2C, Low-Voltage Linear
Taper Digital Potentiometer
Typical Operating Circuit
(All voltages referenced to GND.)
VDD ........................................................................-0.3V to +6V
H, W, L (charge pump enabled) ..........................-0.3V to +5.5V
H, W, L (charge pump disabled) ..................-0.3V to the lower of
(VDD + 0.3V) or +6V
ADDR0 ..................... -0.3V to the lower of (VDD + 0.3V) or +6V
All Other Pins .........................................................-0.3V to +6V
Continuous Current into H, W, and L
MAX5395L ........................................................................5mA
MAX5395M .......................................................................2mA
MAX5395N .......................................................................1mA
Maximum Current into Any Input ........................................50mA
Continuous Power Dissipation (TA = +70°C)
TDFN (derate 11.9mW/°C above +70°C) .................953.5mW
Operating Temperature Range ........................ -40°C to +125°C
Storage Temperature Range ........................... -65°C to + 150°C
Junction Temperature ......................................................+150°C
Lead Temperature (soldering, 10s) ................................+ 300°C
Soldering Temperature (reflow) ......................................+260°C
TDFN
Junction-to-Ambient Thermal Resistance (θJA) .......83.9°C/W Junction-to-Ambient Thermal Resistance (θJC) .......37.0°C/W
(Note 1)
(VDD = 1.7V to 5.5V, VH = V
DD, VL = GND, TA = -40°C to +125°C, unless otherwise noted. Typical values are at VDD = 1.8V,
TA = +25°C.) (Note 2)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
RESOLUTION
256-Tap Family N 256 Tap
DC PERFORMANCE (Voltage-Divider Mode)
Integral Nonlinearity (Note 3) INL -1.0 +1.0 LSB
Differential Nonlinearity DNL (Note 3) -0.5 +0.5 LSB
Ratiometric Resistor Tempco (DVW/VW)/DT, VH = VDD, VL = GND, No
Load 5ppm/°C
Full-Scale Error (Code FFh)
Charge pump enabled, 1.7V < VDD < 5.5V -0.5
LSB
Charge pump disabled,
2.6V < VDD < 5.5V
MAX5395M
MAX5395N -0.5
MAX5395L -1.0
Zero-Scale Error (Code 00h)
Charge pump enabled, 1.7V < VDD < 5.5V +0.5
LSB
Charge pump disabled,
2.6V < VDD < 5.5V
MAX5395M
MAX5395N +0.5
MAX5395L +1.0
DC PERFORMANCE (Variable Resistor Mode)
Integral Nonlinearity (Note 4) R-INL
Charge pump enabled, 1.7V < VDD < 5.5V -1.0 +1.0
LSB
Charge pump disabled,
2.6V < VDD < 5.5V
MAX5395M
MAX5395N -1.0 +1.0
MAX5395L -1.5 +1.5
Differential Nonlinearity R-DNL (Note 4) -0.5 +0.5 LSB
Wiper Resistance (Note 5) RWL
Charge pump enabled, 1.7V < VDD < 5.5V 25 50
Charge pump disabled, 2.6V < VDD < 5.5V 200
MAX5395 Single, 256-Tap Volatile, I2C, Low-Voltage Linear
Taper Digital Potentiometer
www.maximintegrated.com Maxim Integrated
2
Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer
board. For detailed information on package thermal considerations, refer to www.maximintegrated.com/thermal-tutorial.
Absolute Maximum Ratings
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.
Package Thermal Characteristics
Electrical Characteristics
(VDD = 1.7V to 5.5V, VH = V
DD, VL = GND, TA = -40°C to +125°C, unless otherwise noted. Typical values are at VDD = 1.8V,
TA = +25°C.) (Note 2)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
DC PERFORMANCE (Resistor Characteristics)
Terminal Capacitance CH, CLMeasured to GND 10 pF
Wiper Capacitance CWMeasured to GND 20 pF
End-to-End Resistor Tempco TCR No load 50 ppm/°C
End-to-End Resistor Tolerance Wiper not connected -25 +25 %
AC PERFORMANCE
-3dB Bandwidth BW Code = 80h, 10pF load,
VDD = 1.8V
10kΩ 1600
kHz
50kΩ 340
100kΩ 165
Total Harmonic Distortion Plus
Noise THD+N (Note 6) 0.035 %
Wiper Settling Time tS(Note 7)
10kΩ 190
ns
50kΩ 400
100kΩ 664
Charge-Pump Feedthrough at W VRW 600 nVRMS
POWER SUPPLIES
Supply Voltage Range VDD 1.7 5.5 V
Terminal Voltage Range
(H, W, L to GND)
Charge pump enabled, 1.7V < VDD < 5.5V 05.25 V
Charge pump disabled, 2.6V < VDD < 5.5V 0VDD
Supply Current (Note 8) IVDD
Charge pump disabled, 1.7V 0.3 1.4
µA
Charge pump disabled, 2.5V 0.4 1.7
Charge pump disabled, 5.5V 1.0 4.0
Charge pump enabled,
1.7V < VDD < 5.5V
VDD = 5.5V 25 50
VDD = 1.7V 20 45
DIGITAL INPUTS
Minimum Input High Voltage VIH
2.6V < VDD < 5.5V 70 % x
VDD
1.7V < VDD < 2.6V 80
Maximum Input Low Voltage VIL
2.6V < VDD < 5.5V 30 % x
VDD
1.7V < VDD < 2.6V 20
Input Leakage Current -1 +1 µA
Input Capacitance 5pF
ADDR0 Pullup/Pulldown Strength RPURRPD (Note 9) 60 kΩ
TIMING CHARACTERISTICS (Note 10)
Maximum SCL Frequency fSCL 400 kHz
Setup Time for START Condition tSU:STA 0.6 µs
MAX5395 Single, 256-Tap Volatile, I2C, Low-Voltage Linear
Taper Digital Potentiometer
www.maximintegrated.com Maxim Integrated
3
Electrical Characteristics (continued)
(VDD = 1.7V to 5.5V, VH = V
DD, VL = GND, TA = -40°C to +125°C, unless otherwise noted. Typical values are at VDD = 1.8V,
TA = +25°C.) (Note 2)
Note 2: All devices are production tested at TA = +25°C and are guaranteed by design and characterization for TA = -40°C to
+125°C.
Note 3: DNL and INL are measured with the potentiometer configured as a voltage-divider with VH = 5.25V (QP enabled) or VDD
(QP disabled) and VL = GND. The wiper terminal is unloaded and measured with an ideal voltmeter.
Note 4: R-DNL and R-INL are measured with the potentiometer configured as a variable resistor (Figure 1). H is unconnected and
L = GND.
For charge pump enabled, VDD = 1.7V to 5.5V, 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.
For charge pump disabled and VDD = 5.5V, 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.
For charge pump disabled and VDD = 2.6V, the wiper terminal is driven with a source current of 200μA for the 10kΩ
configuration, 40μA for the 50kΩ configuration, and 20μA for the 100kΩ configuration.
Note 5: The wiper resistance is the maximum value measured by injecting the currents given in Note 4 into W with L = GND.
RW = (VW - VH)/IW.
Note 6: Measured at W with H driven with a 1kHz, 0V to VDD amplitude tone and VL = GND. Wiper at midscale with a 10pF load.
Note 7: Wiper-settling time is the worst-case 0-to-50% rise time, measured between tap 0 and tap 127. H = VDD, L = GND, and
the wiper terminal is loaded with 10pF capacitance to ground.
Note 8: Digital Inputs at VDD or GND.
Note 9: An unconnected condition on the ADDR0 pin is sensed via a pullup and pulldown operation. For proper operation, the
ADDR0 pin should be tied to VDD, GND, or left unconnected with minimal capacitance.
Note 10: Digital timing is guaranteed by design and characterization, and is not production tested.
Figure 1. Voltage-Divider and Variable Resistor Configurations
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Hold Time for START Condition tHD:STA 0.6 µs
SCL High Time tHIGH 0.6 µs
SCL Low Time tLOW 1.3 µs
Data Setup Time tSU:DAT 100 ns
Data Hold Time tHD:DAT 0µs
SDA, SCL Rise Time tR0.3 µs
SDA, SCL Fall Time tF0.3 µs
Setup Time for STOP Conditions tSU:STO 0.6 µs
Bus Free Time Between STOP
and START Conditions tBUF 1.3 µs
Pulse-Suppressed Spike Width tSP 50 ns
Capacitive Load for Each Bus CB400 pF
W
H
L
W
N.C.
L
MAX5395 Single, 256-Tap Volatile, I2C, Low-Voltage Linear
Taper Digital Potentiometer
www.maximintegrated.com Maxim Integrated
4
Electrical Characteristics (continued)
(VDD = 1.8V, TA = +25°C, unless otherwise noted.)
SUPPLY CURRENT vs. TEMPERATURE
MAX5395 toc01
TEMPERATURE (°C)
SUPPLY CURRENT (μA)
1109580655035205-10-25
40
0
-40 125
5
10
15
20
25
30
35
VDD = 1.8V
RESISTANCE (W-TO-L)
vs. TAP POSITION (10k)
MAX5395 toc04
TAP POSITION
W-TO-L RESISTANCE (k)
1
2
3
4
5
6
7
8
9
10
0
0 256224192128 16064 9632
WIPER RESISTANCE
vs. WIPER VOLTAGE
WIPER VOLTAGE (V)
WIPER RESISTANCE ()
0.5
0
5
0 1.0
MAX5395 toc07a
VDD = 2.6V, QP OFF
VDD = 5V, QP OFF
5.04.54.03.53.02.52.01.5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
SUPPLY CURRENT
vs. DIGITAL INPUT VOLTAGE
MAX5395 toc02
DIGITAL INPUT VOLTAGE (V)
SUPPLY CURRENT (µA)
4321
200
400
600
800
1000
1200
1400
1600
1800
2000
2200
2400
2600
0
0 5
VDD = 5V
(LOW-HIGH)
VDD = 3.3V
(LOW-HIGH)
VDD = 1.8V
(LOW-HIGH)
VDD = 1.8V
(HIGH-LOW)
VDD = 3.3V
(HIGH-LOW)
VDD = 5V
(HIGH-LOW)
RESISTANCE (W-TO-L)
vs. TAP POSITION (50k)
MAX5395 toc05
TAP POSITION
W-TO-L RESISTANCE (k)
5
10
15
20
25
30
35
40
45
50
0
0 256224192128 16064 9632
5
10
15
20
25
30
35
WIPER RESISTANCE
vs. WIPER VOLTAGE
WIPER VOLTAGE (V)
WIPER RESISTANCE ()
0.5
0
0 1.0
MAX5395 toc07b
VDD = 1.8V, QP ON
5.04.54.03.53.02.52.01.5
40
SUPPLY CURRENT vs. INPUT VOLTAGE
MAX5395 toc03
INPUT VOLTAGE (V)
4.553.602.651.70 5.50
SUPPLY CURRENT (μA)
40
0
5
10
15
20
25
30
35
TA = -40°C
TA = +25°C
TA = +125°C
RESISTANCE (W-TO-L)
vs. TAP POSITION (100k)
MAX5395 toc06
TAP POSITION
W-TO-L RESISTANCE (k)
10
20
30
40
50
60
70
80
90
100
0
0 256224192128 16064 9632
END-TO-END RESISTANCE PERCENTAGE
CHANGE vs. TEMPERATURE
MAX5395 toc08
TEMPERATURE (°C)
END-TO-END RESISTANCE PERCENTAGE CHANGE (%)
1109580655035205-10-25
-0.2
-40 125
0
0.2
0.4
0.6
0.8
50k
10k
100k
MAX5395 Single, 256-Tap Volatile, I2C, Low-Voltage Linear
Taper Digital Potentiometer
Maxim Integrated
5
www.maximintegrated.com
Typical Operating Characteristics
(VDD = 1.8V, TA = +25°C, unless otherwise noted.)
TAP-TO-TAP SWITCHING TRANSIENT
(CODE 127 TO 128, 10k)
MAX5395 toc09
200ns/div
VW-L
10mV/div
VSCL
2V/div
POWER-ON TRANSIENT (10k)
MAX5395 toc12a
10µs/div
VW-L
1V/div
VDD
1V/div
MIDSCALE FREQUENCY
RESPONSE (10k)
FREQUENCY (Hz)
GAIN (dB)
1M100k10k1k0.1k
-20
-10
0
10
-30
0.01k 10M
MAX5395 toc13
VDD = 1.8V
VDD = 5V
VIN = 1VP-P
CW = 10pF
TAP-TO-TAP SWITCHING TRANSIENT
(CODE 127 TO 128, 50k)
MAX5395 toc10
200ns/div
VW-L
10mV/div
VSCL
2V/div
POWER-ON TRANSIENT (50k)
MAX5395 toc12b
10µs/div
VW-L
1V/div
VDD
1V/div
MIDSCALE FREQUENCY
RESPONSE (50k)
FREQUENCY (Hz)
GAIN (dB)
1M100k10k1k0.1k
-20
-10
0
10
-30
0.01k 10M
MAX5395 toc14
VDD = 1.8V
VDD = 5V
VIN = 1VP-P
CW = 10pF
TAP-TO-TAP SWITCHING TRANSIENT
(CODE 127 TO 128, 100k)
MAX5395 toc11
200ns/div
VW-L
10mV/div
VSCL
2V/div
POWER-ON TRANSIENT (100k)
MAX5395 toc12c
10µs/div
VW-L
1V/div
VDD
1V/div
MIDSCALE FREQUENCY
RESPONSE (100k)
FREQUENCY (Hz)
GAIN (dB)
1M100k10k1k0.1k
-20
-10
0
10
-30
0.01k 10M
MAX5395 toc15
VDD = 1.8V
VDD = 5V
VIN = 1VP-P
CW = 10pF
MAX5395 Single, 256-Tap Volatile, I2C, Low-Voltage Linear
Taper Digital Potentiometer
Maxim Integrated
6
www.maximintegrated.com
Typical Operating Characteristics (continued)
(VDD = 1.8V, TA = +25°C, unless otherwise noted.)
TOTAL HARMONIC DISTORTION PLUS NOISE
vs. FREQUENCY
MAX5395 toc16
FREQUENCY (kHz)
THD+N (%)
1010.1
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
0.18
0.20
0
0.01 100
10k50k
100k
CHARGE-PUMP FEEDTHROUGH AT W
MAX5395 toc17
FREQUENCY (MHz)
0.50 2.00
VOLTAGE (nVRMS)
100
200
300
400
500
600
700
800
900
1000
0
1.75
1.501.251.000.75
100k
50k
10k
VARIABLE-RESISTOR DNL
vs. TAP POSITION (10k)
MAX5395 toc18a
TAP POSITION
DNL (LSB)
-0.4
-0.3
-0.2
-0.1
0
0.1
0.2
0.3
0.4
0.5
-0.5
0 256224192128 16064 9632
VDD = 1.8V, VH = 5.0V, CHARGE PUMP ON
VDD = 2.6V, VH = 2.6V, CHARGE PUMP OFF
VDD = 5.0V, VH = 5.0V, CHARGE PUMP OFF
VARIABLE-RESISTOR INL
vs. TAP POSITION (10k)
MAX5395 toc19a
TAP POSITION
INL (LSB)
-0.4
-0.3
-0.2
-0.1
0
0.1
0.2
0.3
0.4
0.5
-0.5
0256224192128 16064 9632
VDD = 2.6V,
VH = 2.6V,
CHARGE
PUMP OFF
VDD = 1.8V, VH = 5.0V, CHARGE PUMP ON
VDD = 5.0V, VH = 5.0V, CHARGE PUMP OFF
VARIABLE-RESISTOR DNL
vs. TAP POSITION (50k)
MAX5395 toc18b
TAP POSITION
DNL (LSB)
-0.4
-0.3
-0.2
-0.1
0
0.1
0.2
0.3
0.4
0.5
-0.5
0 256224192128 16064 9632
VDD = 1.8V, VH = 5.0V, CHARGE PUMP ON
VDD = 2.6V, VH = 2.6V, CHARGE PUMP OFF
VDD = 5.0V, VH = 5.0V, CHARGE PUMP OFF
VARIABLE-RESISTOR INL
vs. TAP POSITION (50k)
MAX5395 toc19b
TAP POSITION
INL (LSB)
-0.4
-0.3
-0.2
-0.1
0
0.1
0.2
0.3
0.4
0.5
-0.5
0256224192128 16064 9632
VDD = 2.6V, VH = 2.6V, CHARGE PUMP OFF
VDD = 1.8V, VH = 5.0V, CHARGE PUMP ON
VDD = 5.0V, VH = 5.0V, CHARGE PUMP OFF
VARIABLE-RESISTOR DNL
vs. TAP POSITION (100k)
MAX5395 toc18c
TAP POSITION
DNL (LSB)
-0.4
-0.3
-0.2
-0.1
0
0.1
0.2
0.3
0.4
0.5
-0.5
0 256224192128 16064 9632
VDD = 1.8V, VH = 5.0V, CHARGE PUMP ON
VDD = 2.6V, VH = 2.6V, CHARGE PUMP OFF
VDD = 5.0V, VH = 5.0V, CHARGE PUMP OFF
VARIABLE-RESISTOR INL
vs. TAP POSITION (100k)
MAX5395 toc19c
TAP POSITION
INL (LSB)
-0.4
-0.3
-0.2
-0.1
0
0.1
0.2
0.3
0.4
0.5
-0.5
0256224192128 16064 9632
VDD = 1.8V, VH = 5.0V, CHARGE PUMP ON
VDD = 2.6V, VH = 2.6V, CHARGE PUMP OFF
VDD = 5.0V, VH = 5.0V, CHARGE PUMP OFF
MAX5395 Single, 256-Tap Volatile, I2C, Low-Voltage Linear
Taper Digital Potentiometer
Maxim Integrated
7
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Typical Operating Characteristics (continued)
(VDD = 1.8V, TA = +25°C, unless otherwise noted.)
VOLTAGE-DIVIDER DNL
vs. TAP POSITION (10k)
MAX5395 toc20a
TAP POSITION
DNL (LSB)
-0.4
-0.3
-0.2
-0.1
0
0.1
0.2
0.3
0.4
0.5
-0.5
0256224192128 16064 9632
VDD = 1.8V, VH = 5.0V, CHARGE PUMP ON
VDD = 2.6V, VH = 2.6V, CHARGE PUMP OFF
VDD = 5.0V, VH = 5.0V, CHARGE PUMP OFF
VOLTAGE-DIVIDER INL
vs. TAP POSITION (10k)
MAX5395 toc21a
TAP POSITION
INL (LSB)
-0.4
-0.3
-0.2
-0.1
0
0.1
0.2
0.3
0.4
0.5
-0.5
0 256224192128 16064 9632
VDD = 1.8V, VH = 5.0V, CHARGE PUMP ON
VDD = 2.6V, VH = 2.6V, CHARGE PUMP OFF
VDD = 5.0V, VH = 5.0V, CHARGE PUMP OFF
VOLTAGE-DIVIDER DNL
vs. TAP POSITION (50k)
MAX5395 toc20b
TAP POSITION
DNL (LSB)
-0.4
-0.3
-0.2
-0.1
0
0.1
0.2
0.3
0.4
0.5
-0.5
0256224192128 16064 9632
VDD = 1.8V, VH = 5.0V, CHARGE PUMP ON
VDD = 2.6V, VH = 2.6V, CHARGE PUMP OFF
VDD = 5.0V, VH = 5.0V, CHARGE PUMP OFF
VOLTAGE-DIVIDER INL
vs. TAP POSITION (50k)
MAX5395 toc21b
TAP POSITION
INL (LSB)
-0.4
-0.3
-0.2
-0.1
0
0.1
0.2
0.3
0.4
0.5
-0.5
0 256224192128 16064 9632
VDD = 1.8V, VH = 5.0V, CHARGE PUMP ON
VDD = 2.6V, VH = 2.6V, CHARGE PUMP OFF
VDD = 5.0V, VH = 5.0V, CHARGE PUMP OFF
VOLTAGE-DIVIDER DNL
vs. TAP POSITION (100k)
MAX5395 toc20c
TAP POSITION
DNL (LSB)
-0.4
-0.3
-0.2
-0.1
0
0.1
0.2
0.3
0.4
0.5
-0.5
0256224192128 16064 9632
VDD = 1.8V, VH = 5.0V, CHARGE PUMP ON
VDD = 2.6V, VH = 2.6V, CHARGE PUMP OFF
VDD = 5.0V, VH = 5.0V, CHARGE PUMP OFF
VOLTAGE-DIVIDER INL
vs. TAP POSITION (100k)
MAX5395 toc21c
TAP POSITION
INL (LSB)
-0.4
-0.3
-0.2
-0.1
0
0.1
0.2
0.3
0.4
0.5
-0.5
0 256224192128 16064 9632
VDD = 1.8V, VH = 5.0V, CHARGE PUMP ON
VDD = 2.6V, VH = 2.6V, CHARGE PUMP OFF
VDD = 5.0V, VH = 5.0V, CHARGE PUMP OFF
MAX5395 Single, 256-Tap Volatile, I2C, Low-Voltage Linear
Taper Digital Potentiometer
Maxim Integrated
8
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Typical Operating Characteristics (continued)
PIN NAME FUNCTION
1 L Low Terminal. The voltage at L can be greater than or less than the voltage at H. Current can flow into or out
of L.
2GND Ground
3ADDR0 Address Input 0. Connected to VDD, GND, or open.
4SDA I2C Serial Data Input
5SCL I2C Clock Input
6VDD Power Supply
7WWiper Terminal
8HHigh Terminal. The voltage at H can be greater than or less than the voltage at L. Current can flow into or
out of H.
EP Exposed Pad. Internally connected to GND. Connect to ground.
1
+
3
4
8
6
5
H
V
DD
SCL
MAX5395
2
7W
L
EP
SDA
GND
TDFN
TOP VIEW
ADDR0
MAX5395 Single, 256-Tap Volatile, I2C, Low-Voltage Linear
Taper Digital Potentiometer
www.maximintegrated.com Maxim Integrated
9
Pin Description
Pin Conguration
Detailed Description
The MAX5395 single, 256-tap volatile, low-voltage
linear taper digital potentiometer offers three end-to-
end resistance values of 10kΩ, 50kΩ, and 100kΩ.
Potentiometer terminals are independent of supply for
voltages up to +5.25V with single-supply operation from
1.7V to 5.5V (charge pump enabled). User-controlled
shutdown modes allow the H, W, or L terminals to be
opened with the wiper position set to zero-code, midcode,
full-code, or the value contained in the wiper register. Ultra-
low-quiescent supply current (< 1µA) can be achieved for
supply voltages between 2.6V and 5.5V by disabling the
internal charge pump and not allowing potentiometer
terminals to exceed the supply voltage by more than
0.3V. The MAX5395 provides a low 50ppm/°C end-to-end
temperature coefficient and features a I2C serial interface.
The small package size, low supply operating voltage,
low supply current, and automotive temperature range
of the MAX5395 make the device uniquely suited for the
portable consumer market and battery-backup industrial
applications.
Charge Pump
The MAX5395 contains an internal charge pump that
guarantees the maximum wiper resistance, RWL, to be
less than 50Ω (25Ω typ) for supply voltages down to
1.7V and allows pins H, W, and L to be driven between
GND and 5.25V independent of VDD. Minimal charge-
pump feedthrough is present at the terminal outputs
and is illustrated by the Charge-Pump Feedthrough
at W vs. Frequency graph in the Typical Operating
Characteristics. The charge pump is on by default but
can be disabled with QP_OFF and enabled with the
QP_ON commands (Table 1). The MAX5395 minimum
supply voltage with charge pump disabled is limited
to 2.6V and terminal voltage cannot exceed -0.3V to
(VDD + 0.3V).
I2C Interface
The MAX5395 feature an I2C/SMBus-compatible, 2-wire
serial interface consisting of a serial data line (SDA) and
a serial clock line (SCL). SDA and SCL enable communication
between the MAX5395 and the master at clock rates up
to 400kHz. Figure 1 shows the 2-wire interface timing
diagram. The master generates SCL and initiates data
transfer on the bus. The master device writes data to the
MAX5395 by transmitting the proper slave address fol-
lowed by the command byte and then the data word. Each
transmit sequence is framed by a START (S) or Repeated
START (Sr) condition and a STOP (P) condition. Each
word transmitted to the MAX5395 is 8 bits long and is fol-
lowed by an acknowledge clock pulse. A master reading
data from the MAX5395 must transmit the proper slave
address followed by a series of nine SCL pulses for each
byte of data requested. The MAX5395 transmit data on
SDA in sync with the master-generated SCL pulses. The
master acknowledges receipt of each byte of data. Each
read sequence is framed by a START or Repeated START
condition, a not acknowledge, and a STOP condition. SDA
operates as both an input and an open-drain output. A pullup
resistor, typically 4.7kΩ, is required on SDA. SCL operates
only as an input. A pullup resistor, typically 4.7kΩ, is required
on SCL if there are multiple masters on the bus, or if the
single master has an open-drain SCL output.
Series resistors in line with SDA and SCL are optional.
Series resistors protect the digital inputs of the MAX5395
from high voltage spikes on the bus lines and mini-
mize crosstalk and undershoot of the bus signals. The
MAX5395 can accommodate bus voltages higher than
VDD up to a limit of +5.5V. Bus voltages lower than VDD
are not recommended and may result in significantly
increased interface currents and data corruption.
The MAX5395 with I2C interface contains a shift register
that decodes the command and address bytes, routing
the data to the register. Data written to a memory register
immediately updates the wiper position. The wiper powers
up in mid position, D[7:0] = 0x80 with charge pump enabled.
H
L
ADDRO
GND
SDA
W
VDD
SCL
MAX5395
I2C
INTERFACE
MAX5395 Single, 256-Tap Volatile, I2C, Low-Voltage Linear
Taper Digital Potentiometer
www.maximintegrated.com Maxim Integrated
10
Functional Diagram
I2C START and STOP Conditions
SDA and SCL idle high when the bus is not in use. A master
initiates communication by issuing a START condition. A
START condition is a high-to-low transition on SDA with
SCL high. A STOP condition is a low-to-high transition on
SDA while SCL is high (Figure 2). A START condition from
the master signals the beginning of a transmission to the
MAX5395. The master terminates transmission and frees
the bus, by issuing a STOP condition. The bus remains
active if a Repeated START condition is generated instead
of a STOP condition.
I2C Early STOP and Repeated START Conditions
The MAX5395 recognizes a STOP condition at any point
during data transmission except if the STOP condition
occurs in the same high pulse as a START condition.
For proper operation, do not send a STOP condition
during the same SCL high pulse as the START condition.
Transmissions ending in an early STOP condition will not
impact the internal device settings. If the STOP occurs
during a readback byte, the transmission is terminated
and a later read mode request will begin transfer of the
requested register data from the beginning. See Figure 3.
It is possible to interrupt a transmission to a MAX5395
with a new START (Repeated START) condition (perhaps
addressing another device), which leaves the input registers
with data that has not been transferred to the internal
registers. The unused data will not be stored under these
conditions. The aborted MAX5395 I2C sequence will have
no effect on the part.
I2C Acknowledge
In write mode, the acknowledge bit (ACK) is a clocked
9th bit that the MAX5395 uses to handshake receipt of
each byte of data as shown in Figure 4. The MAX5395
pulls down SDA during the entire master-generated 9th
clock pulse if the previous byte is successfully received.
Monitoring ACK allows for detection of unsuccessful data
transfers. An unsuccessful data transfer occurs if a receiving
device is busy or if a system fault has occurred. In the
event of an unsuccessful data transfer, the bus master will
retry communication.
Figure 2. I2C Timing Diagram
Figure 3. I2C START(s), Repeated START(S), and STOP(S) Conditions
SDA
SCL
START
CONDITION
(S)
t
LOW
t
BUF
t
HIGH
t
HD:STA
t
HD:STA
t
SU:DAT
t
R
t
F
t
SU:STD
REPEATED
START CONDITION
(Sr)
ACKNOWLEDGE (A) STOP CONDITION
(P)
START CONDITION
(S)
t
HD-DAT
t
SU:DTA
SCL
SDA
S Sr P
VALID START, REPEATED START, AND STOP PULSES
P S PS P PS
INVALID START/STOP PULSE PAIRINGS-ALL WILL BE RECOGNIZED AS STARTS
MAX5395 Single, 256-Tap Volatile, I2C, Low-Voltage Linear
Taper Digital Potentiometer
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11
In read mode, the master pulls down SDA during the
9th clock cycle to acknowledge receipt of data from the
MAX5395. An acknowledge is sent by the master after
each read byte to allow data transfer to continue. A not-
acknowledge is sent when the master reads the final byte
of data from the MAX5395, followed by a STOP condition.
I2C Slave Address
The slave address is defined as the seven most significant
bits (MSBs) followed by the R/W bit. See Figure 5 and
Figure 6. The five most significant bits are 01010 with the
3 LSBs determined ADDR0 as shown in Table 1. Setting
the R/W bit to 1 configures the MAX5395 for read mode.
Setting the R/W bit to 0 configures the MAX5395 for write
mode. The slave address is the first byte of information
sent to the MAX5395 after the START condition.
The MAX5395 has the ability to detect an unconnected
(N.C.) state on the ADDR0 input for additional address
flexibility; if disconnecting the ADDR0 input, be certain to
minimize all loading on the ADDR0 input (i.e. provide a
landing for ADDR0, but do not allow any board traces).
I2C Message Format for Writing
A master device communicates with the MAX5395 by
transmitting the proper slave address followed by command
and data word. Each transmit sequence is framed by a
START or Repeated START condition and a STOP condition as
described above. Each word is 8 bits long and is always
followed by an acknowledge clock (ACK) pulse as shown
in Figure 5. The first byte contains the address of the
MAX5395 with R/W = 0 to indicate a write. The second
byte contains the command to be executed and the third
byte contains the data to be written.
I2C Message Format for Readback Operations
Each readback sequence is framed by a START or
Repeated START condition and a STOP condition. Each
word is 8 bits long and is followed by an acknowledge
clock pulse as shown in Figure 6. The first byte contains
the address of the MAX5395 with R/W = 0 to indicate a
write. The second byte contains the register that is to
be read back. There is a Repeated START condition,
followed by the device address with R/W = 1 to indicate a
Table 1. I2C Slave Address LSBs
Figure 5. I2C Complete Write Serial Transmission
Figure 4. I2C Acknowledge
ADDR0 A1 A0 SLAVE ADDRESS
GND 0 0 0101000
N.C. 0 1 0101001
VDD 1 1 0101011
0 1 0 1 0 A1 A0 W D D D D D D D DA A ASEE REGISTER OPTIONS
SDA
START STOP
WRITE ADDRESS
BYTE #1: I2C SLAVE ADDRESS
WRITE REGISTER
BYTE #2: REG # = N
WRITE DATA
BYTE #3: DATA BYTE B[7:0]
SCL
REG N UPDATED
ACK. GENERATED BY MAX5395L/
MAX5395M/MAX5395N
ACK. GENERATED BY I2C MASTER
1
SCL
START
CONDITION
SDA
2 9
CLOCK PULSE
FOR
ACKNOWLEDGMENT
ACKNOWLEDGE
NOT ACKNOWLEDGE
MAX5395 Single, 256-Tap Volatile, I2C, Low-Voltage Linear
Taper Digital Potentiometer
www.maximintegrated.com Maxim Integrated
12
read and an acknowledge clock. The master has control
of the SCL line but the MAX5395 takes over the SDA
line. The final byte in the frame contains the register data
readback followed by a STOP condition. If additional
bytes beyond those required to read back the requested
data are provided, the MAX5395 will continue to read
back ones.
The wiper register and the configuration register are
the only two registers that support readback (Table 2).
Readback of all other registers is not supported and
results in the readback of ones.
D[7:0]: Wiper position
QP: Charge pump status, 1 is enabled, 0 is disabled.
HSW: H terminal switch status, 0 is closed, 1 is open
WSW: W terminal switch status, 0 is closed, 1 is open
LSW: L terminal switch status, 0 is closed, 1 is open
TSEL[1:0]: Tap select, 00- wiper is at contents of wiper
register, 01 – wiper is at 0x00, 10 – wiper is at 0x80, 11 –
wiper is at 0xFF.
General Call Support
The MAX5395 supports software reset through general
call address 0x00 followed by R/W = 0, followed by 0x06
data. A software reset of the MAX5395 will return the part
to the power-on default conditions. The MAX5395 will
ACK the general call address and any command byte
following, but will not support any general call features
other than software reset.
Figure 6. Standard I2C Register Read Sequence
Table 2. I2C READ Command Byte Summary
REGISTER COMMAND BYTE DATA BYTE
C7 C6 C5 C4 C3 C2 C1 C0 D7 D6 D5 D4 D3 D2 D1 D0
WIPER 00000000D7 D6 D5 D4 D3 D2 D1 D0
CONFIG 10000000QP 0 0 HSW LSW WSW TSEL[1:0]
0 1 0 1 0 A1 A0 W 0 D D D D D D D D ~A1 0 1 0A A A1 A0 R ASEE REGISTER OPTIONSSDA
START STOP
WRITE ADDRESS
BYTE #1: I2C SLAVE ADDRESS
WRITE COMMAND
BYTE #2: COMMAND BYTE
READ ADDREESS
BYTE #3: I2C SLAVE ADDRESS
READ DATA
BYTE #4: DATA BYTE B[7:0]
REPEATED
START
SCL
ACK. GENERATED BY MAX5395L/
MAX5395M/MAX5395N
ACK. GENERATED BY I2C MASTER
MAX5395 Single, 256-Tap Volatile, I2C, Low-Voltage Linear
Taper Digital Potentiometer
www.maximintegrated.com Maxim Integrated
13
WIPER Command
The data byte writes to the wiper register and the
potentiometer moves to the appropriate position. D[7:0]
indicates the position of the wiper. D[7:0] = 0x00 moves
the wiper to the position closest to L. D[7:0] = 0xFF moves
the wiper closest to H. D[7:0] = 0x80 following power-on.
SD_CLR Command
Removes any existing shutdown condition. Connects all
potentiometer terminals and returns the wiper to the value
stored in the wiper register. The command does not affect
the current status of the charge pump.
SD_H_WREG Command
Opens the H terminal and maintains the wiper at the
wiper register location. Writes cannot be made to the
wiper register while shutdown mode is engaged. Clearing
shutdown mode will close the H terminal and allow the
wiper register to be written. A RST will also deassert
shutdown mode and return the wiper to midscale (0x80).
This command does not affect the charge-pump status.
SD_H_ZERO Command
Moves wiper to zero-scale position (0x00) and opens the
H terminal. The wiper register remains unaltered. Writes
cannot be made to the wiper register while shutdown
mode is engaged. Clearing shutdown mode will return the
wiper to the position contained in the wiper register and
close the H terminal. A RST will also deassert shutdown
mode and return the wiper to midscale (0x80). This
command does not affect the charge-pump status.
SD_H_MID Command
Moves wiper to midscale position (0x80) and opens the
H terminal. The wiper register remains unaltered. Writes
cannot be made to the wiper register while shutdown
mode is engaged. Clearing shutdown mode will return the
wiper to the position contained in the wiper register and
close the H terminal. A RST will also deassert shutdown
mode and return the wiper to midscale (0x80). This
command does not affect the charge-pump status.
SD_H_FULL Command
Moves wiper to full-scale position (0xFF) and opens the
H terminal. The wiper register remains unaltered. Writes
cannot be made to the wiper register while shutdown
mode is engaged. Clearing shutdown mode will return the
wiper to the position contained in the wiper register and
close the H terminal. A RST will also deassert shutdown
mode and return the wiper to midscale (0x80). This
command does not affect the charge-pump status.
Table 3. I2C Write Command Byte Summary
COMMAND ADDRESS BYTE COMMAND BYTE DATA BYTE
S
A6 A5 A4 A3 A2 A1 A0 R/W
A
C7 C6 C5 C4 C3 C2 C1 C0
A
D7 D6 D5 D4 D3 D2 D1 D0
A P
WIPER
See Table 1
0 00000000 D7 D6 D5 D4 D3 D2 D1 D0
SD_CLR 0 10000000
Don’t Care
SD_H_WREG 0 10010000
SD_H_ZERO 0 10010001
SD_H_MID 0 10010010
SD_H_FULL 0 10010011
SD_L_WREG 0 10001000
SD_L_ZERO 0 10001001
SD_L_MID 0 10001010
SD_L_FULL 0 10001011
SD_W 0 100001XX
QP_OFF 0 10100000
QP_ON 0 10100001
RST 0 11000000
MAX5395 Single, 256-Tap Volatile, I2C, Low-Voltage Linear
Taper Digital Potentiometer
www.maximintegrated.com Maxim Integrated
14
SD_L_WREG Command
Opens the L terminal and maintains the wiper at the
wiper register location. Writes cannot be made to the
wiper register while shutdown mode is engaged. Clearing
shutdown mode will close the L terminal and allow wiper
register to be written. A RST will also deassert shutdown
mode and return the wiper to midscale (0x80). This
command does not affect the charge-pump status.
SD_L_ZERO Command
Moves wiper to zero-scale position (0x00) and opens the
L terminal. The wiper register remains unaltered. Writes
cannot be made to the wiper register while shutdown
mode is engaged. Clearing shutdown mode will return the
wiper to the position contained in the wiper register and
close the L terminal. A RST will also deassert shutdown
mode and return the wiper to midscale (0x80). This
command does not affect the charge-pump status.
SD_L_MID Command
Moves wiper to midscale position (0x80) and opens the
L terminal. The wiper register remains unaltered. Writes
cannot be made to the wiper register while shutdown
mode is engaged. Clearing shutdown mode will return the
wiper to the position contained in the wiper register and
close the L terminal. A RST will also deassert shutdown
mode and return the wiper to midscale (0x80). This
command does not affect the charge-pump status.
SD_L_FULL Command
Moves wiper to full-scale position (0xFF) and opens the
L terminal. The wiper register remains unaltered. Writes
cannot be made to the wiper register while shutdown
mode is engaged. Clearing shutdown mode will return the
wiper to the position contained in the wiper register and
close the L terminal. A RST will also deassert shutdown
mode and return the wiper to midscale (0x80). This
command does not affect the charge-pump status.
SD_W Command
Opens the W terminal keeping the internal tap position
the same as the wiper register. Writes cannot be made
to the wiper registers while shutdown mode is engaged.
Clearing shutdown mode will return the wiper to the
position contained in the wiper register and close W
terminal. A RST will also deassert shutdown mode and
return the wiper to midscale (0x80). This command does
not affect the charge-pump status.
QP_OFF Command
Disables the onboard charge pump and places device in
low power mode. Low supply voltage is limited to 2.6V.
QP_ON Command
Enables the onboard charge pump to allow low-supply
voltage operation. This is the power-on default condition.
Low supply voltage is 1.7V.
RST Command
Returns the device to power-on default conditions. Resets
the wiper register to midscale (0x80), enables charge
pump, and deasserts any shutdown modes.
MAX5395 Single, 256-Tap Volatile, I2C, Low-Voltage Linear
Taper Digital Potentiometer
www.maximintegrated.com Maxim Integrated
15
Note: All devices operate over the -40°C to +125°C temperature range.
+Denotes a lead(Pb)-free/RoHS-compliant package.
T = Tape and reel.
*EP = Exposed pad.
PART PIN-PACKAGE INTERFACE TAPS END-TO-END
RESISTANCE (kΩ)
MAX5395LATA+T 8 TDFN-EP* I2C256 10
MAX5395MATA+T 8 TDFN-EP* I2C256 50
MAX5395NATA+T 8 TDFN-EP* I2C256 100
PACKAGE
TYPE
PACKAGE
CODE
OUTLINE
NO.
LAND PATTERN
NO.
8 TDFN-EP T822+2 21-0168 90-0065
MAX5395 Single, 256-Tap Volatile, I2C, Low-Voltage Linear
Taper Digital Potentiometer
www.maximintegrated.com Maxim Integrated
16
Package Information
For the latest package outline information and land patterns
(footprints), go to www.maximintegrated.com/packages. Note
that a “+”, “#”, or “-” in the package code indicates RoHS status
only. Package drawings may show a different suffix character, but
the drawing pertains to the package regardless of RoHS status.
Chip Information
PROCESS: BiCMOS
Ordering Information
REVISION
NUMBER
REVISION
DATE DESCRIPTION PAGES
CHANGED
07/12 Initial release
19/12 Revised the Absolute Maximum Ratings 2
211/14 Removed automotive references from data sheet 1, 10
32/16 Add charge pump current at various disabled conditions 3
Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses
are implied. Maxim Integrated reserves the right to change the circuitry and specications without notice at any time. The parametric values (min and max limits)
shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance.
Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc.
MAX5395 Single, 256-Tap Volatile, I2C, Low-Voltage Linear
Taper Digital Potentiometer
© 2016 Maxim Integrated Products, Inc.
17
Revision History
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim Integrated’s website at www.maximintegrated.com.