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An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
MAX660
SNOS405B –NOVEMBER 1999–REVISED MAY 2017
MAX660 Switched Capacitor Voltage Converter
1
1 Features
1• Inverts or Doubles Input Supply Voltage
• Narrow SO-8 Package
• 6.5-ΩTypical Output Resistance
• 88% Typical Conversion Efficiency at 100 mA
• Selectable Oscillator Frequency: 10 kHz/80 kHz
2 Applications
• Laptop Computers
• Cellular Phones
• Medical Instruments
• Operational Amplifier Power Supplies
• Interface Power Supplies
• Handheld Instruments
3 Description
The MAX660 CMOS charge-pump voltage converter
is a versatile unregulated switched-capacitor inverter
or doubler. Operating from a wide 1.5-V to 5.5-V
supply voltage, the MAX660 uses two low-cost
capacitors to provide 100 mA of output current
without the cost, size and EMI related to inductor-
based converters. With an operating current of only
120 µA and operating efficiency greater than 90% at
most loads, the MAX660 provides ideal performance
for battery-powered systems. MAX660 devices can
be operated directly in parallel to lower output
impedance, thus providing more current at a given
voltage.
The FC (frequency control) pin selects between a
nominal 10-kHz or 80-kHz oscillator frequency. The
oscillator frequency can be lowered by adding an
external capacitor to the OSC pin. Also, the OSC pin
may be used to drive the MAX660 with an external
clock up to 150 kHz. Through these methods, output
ripple frequency and harmonics may be controlled.
Additionally, the MAX660 may be configured to divide
a positive input voltage precisely in half. In this mode,
input voltages as high as 11 V may be used.
Device Information(1)
PART NUMBER PACKAGE BODY SIZE (NOM)
MAX660 SOIC (8) 4.90 mm × 3.91 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
Voltage Inverter Positive Voltage Doubler
2
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Table of Contents
1 Features.................................................................. 1
2 Applications ........................................................... 1
3 Description............................................................. 1
4 Revision History..................................................... 2
5 Device Comparison Tables................................... 3
6 Pin Configuration and Functions......................... 4
7 Specifications......................................................... 5
7.1 Absolute Maximum Ratings ...................................... 5
7.2 ESD Ratings ............................................................ 5
7.3 Recommended Operating Conditions....................... 5
7.4 Thermal Information.................................................. 5
7.5 Electrical Characteristics........................................... 6
7.6 Typical Characteristics.............................................. 7
8 Parameter Measurement Information .................. 9
8.1 MAX660 Test Circuit................................................. 9
9 Detailed Description............................................ 10
9.1 Overview................................................................. 10
9.2 Functional Block Diagram....................................... 10
9.3 Feature Description................................................. 11
9.4 Device Functional Modes........................................ 11
10 Application and Implementation........................ 12
10.1 Application Information.......................................... 12
10.2 Typical Applications ............................................. 12
10.3 Split V+ in Half ...................................................... 18
11 Power Supply Recommendations ..................... 18
12 Layout................................................................... 19
12.1 Layout Guidelines ................................................. 19
12.2 Layout Example .................................................... 19
13 Device and Documentation Support................. 20
13.1 Device Support...................................................... 20
13.2 Receiving Notification of Documentation Updates 20
13.3 Community Resources.......................................... 20
13.4 Trademarks........................................................... 20
13.5 Electrostatic Discharge Caution............................ 20
13.6 Glossary................................................................ 20
14 Mechanical, Packaging, and Orderable
Information........................................................... 20
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision A (October 2016) to Revision B Page
• Changed Figure 5 caption from "Efficiency vs Oscillator Frequency" to "Efficiency vs Load Current" ................................. 7
Changes from Original (SNOS405) to Revision A Page
• Added additional info to DescriptionDevice Information and Pin Configuration and Functions sections, ESD Ratings
and Thermal Information tables, Feature Description,Device Functional Modes,Application and Implementation,
Power Supply Recommendations,Layout,Device and Documentation Support, and Mechanical, Packaging, and
Orderable Information sections .............................................................................................................................................. 1
• Deleted obsolete device number information from Device Comparison table ...................................................................... 3
• Deleted lead temperature spec from Abs Max as it is in POA .............................................................................................. 5
• Added additional thermal values; changed RθJA from "170°C/W" to "114.4°C/W" ................................................................. 5
• Changed "PL" to "PM" and "PF" to PJ" - manufacturers changed their part number prefix ............................................... 14
• Changed "Sprague" to "Vishay Sprague" per website ........................................................................................................ 14
3
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5 Device Comparison TablesLM2664 LM2665 MAX660
Package SOT-23 (6) SOT-23 (6) SOIC
Supply current (typical) (mA) 0.22 0.22 0.12 at 10 kHz, 1 at 80 kHz
Output (typical) (Ω) 12 12 6.5
Oscillator (kHz) 80 80 10, 80
Input (V) 1.8 to 5.5 1.8 to 5.5 1.8 to 5.5
Output mode(s) Invert Double Invert, Double
MAX660 LM2662 LM2663
Package SOIC, VSSOP (8) SOIC (8) SOIC (8)
Supply current (typical) (mA) 0.12 at 10 kHz, 1 at 80 kHz 0.3 at 10 kHz, 1.3 at 70 kHz 1.3
Output (typical) (Ω) 6.5 3.5 3.5
Oscillator (kHz) 10, 80 10, 70 70
Input (V) 1.8 to 5.5 1.8 to 5.5 1.8 to 5.5
Output mode(s) Invert, Double Invert, Double Invert, Double
4
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6 Pin Configuration and Functions
D Package
8-Pin SOIC
Top View
Pin Functions
PIN I/O DESCRIPTION
NAME NO. VOLTAGE INVERTER VOLTAGE DOUBLER
CAP+ 2 Power Connect this pin to the positive terminal of charge-pump
capacitor. Same as inverter
CAP– 4 Power Connect this pin to the negative terminal of charge-pump
capacitor. Same as inverter
FC 1 Input Frequency control for internal oscillator:
FC = open, ƒOSC = 10 kHz (typical);
FC = V+, ƒOSC = 80 kHz (typical);
FC has no effect when OSC pin is driven externally Same as inverter
GND 3 Ground Power supply ground input. Power supply positive voltage input
LV 6 Input Low-voltage operation input. Tie LV to GND when input
voltage is less than 3.5 V. Above 3.5 V, LV can be
connected to GND or left open. When driving OSC with
an external clock, LV must be connected to GND. LV must be tied to OUT.
OSC 7 Input Oscillator control input. OSC is connected to an internal
15-pF capacitor. An external capacitor can be connected
to slow the oscillator. Also, an external clock can be
used to drive OSC.
Same as inverter except that OSC cannot
be driven by an external clock
OUT 5 Power Negative voltage output Positive supply ground input
V+ 8 Power Power supply positive voltage input Positive voltage output
5
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(1) Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings
only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended
Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
(2) If Military/Aerospace specified devices are required, contact the Texas Instruments Sales Office/ Distributors for availability and
specifications.
(3) OUT may be shorted to GND for one second without damage. However, shorting OUT to V+ may damage the device and must be
avoided. Also, for temperatures above 85°C, OUT must not be shorted to GND or V+, or device may be damaged.
(4) The maximum allowable power dissipation is calculated by using PD_MAX = (TJ_MAX −TA) / RθJA, where TJ_MAX is the maximum junction
temperature, TAis the ambient temperature, and RθJA is the junction-to-ambient thermal resistance of the specified package.
7 Specifications
7.1 Absolute Maximum Ratings
MIN MAX UNIT
Supply voltage (V+ to GND, or GND to OUT) 6 V
LV (OUT −0.3 V) GND + 3 V)
FC, OSC The least negative of (OUT −0.3 V)(V+ −6 V) to
(V+ 0.3 V)
V+ and OUT continuous output current 120 mA
Output short-circuit duration to GND(3) 1 sec
Power dissipation, TA= 25°C(4) 735 mW
TJ, maximum(4) 150 °C
Operating junction temperature −40 85 °C
Storage temperature, Tstg −65 150 °C
(1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
7.2 ESD Ratings VALUE UNIT
V(ESD) Electrostatic discharge Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001(1) ±2000 V
7.3 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted) MIN NOM MAX UNIT
V+ (supply voltage) Inverter, LV = open 3.5 5.5 VInverter, LV = GND 1.5 5.5
Doubler, LV = out 2.5 5.5
Junction temperature (TJ) –40 85 °C
(1) For more information about traditional and new thermal metrics, see Semiconductor and IC Package Thermal Metrics.
7.4 Thermal Information
THERMAL METRIC(1) MAX660
UNITSOIC (D)
8 PINS
RθJA Junction-to-ambient thermal resistance 114.4 °C/W
RθJC(top) Junction-to-case (top) thermal resistance 61.4 °C/W
RθJB Junction-to-board thermal resistance 55.5 °C/W
ψJT Junction-to-top characterization parameter 9.8 °C/W
ψJB Junction-to-board characterization parameter 54.9 °C/W
6
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(1) In the test circuit, capacitors C1 and C2 are 0.2-Ωmaximum ESR capacitors. Capacitors with higher ESR increase output resistance,
reduce output voltage, and efficiency.
(2) Specified output resistance includes internal switch resistance and capacitor ESR.
(3) The minimum limit for this parameter is different from the limit of 3 V for the industry-standard 660 product. For inverter operation with
supply voltage below 3.5 V, connect the LV pin to GND.
7.5 Electrical Characteristics
Unless otherwise specified: Limits apply for TJ= 25°C, V+ = 5 V, FC = open, C1 = C2 = 150 μF.(1)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
V+(2) Supply voltage RL= 1 kΩ
Inverter LV = open(3),
TJ= –40°C to 85°C 3.5 5.5
V
Inverter, LV = GND,
TJ= –40°C to 85°C 1.5 5.5
Doubler, LV = OUT,
TJ= –40°C to 85°C 2.5 5.5
IQSupply current No load, LV = open
FC = open 0.12
mA
FC = open,
TJ= –40°C to 85°C 0.5
FC = V+ 1
FC = V+,
TJ= –40°C to 85°C 3
ILOutput current TA≤85°C, OUT ≤ −4 V 100 mA
TA> 85°C, OUT ≤ −3.8 V 100
ROUT Output resistance(2) IL= 100 mA TA≤85°C 6.5 10
ΩTJ= –40°C to 85°C 10
TA> 85°C, TJ= –40°C to 85°C 12
ƒOSC Oscillator frequency OSC = open
FC = open 10
kHz
FC = open, TJ= –40°C to 85°C 5
FC = V+ 80
FC = V+, TJ= –40°C to 85°C 40
IOSC OSC input current FC = open ±2 µA
FC = V+ ±16
PEFF Power efficiency
RL(1 kΩ) between V+ and OUT 98%
RL(1 kΩ) between V+ and OUT
TJ= –40°C to 85°C 96%
RL(500 Ω) between GND and OUT 96%
RL(500 Ω) between GND and OUT
TJ= –40°C to 85°C 92%
IL= 100 mA to GND 88%
VOEFF Voltage conversion
efficiency No load 99.96%
No load, TJ= –40°C to 85°C 99%
7
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7.6 Typical Characteristics
Circuit of Voltage Inverter and Positive Voltage Doubler.
Figure 1. Supply Current vs Supply Voltage Figure 2. Supply Current vs Oscillator Frequency
Figure 3. Output Source Resistance vs Supply Voltage Figure 4. Output Source Resistance vs Temperature
Figure 5. Efficiency vs Load Current Figure 6. Output Voltage Drop vs Load Current
8
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Typical Characteristics (continued)
Circuit of Voltage Inverter and Positive Voltage Doubler.
Figure 7. Efficiency vs Oscillator Frequency Figure 8. Output Voltage vs Oscillator Frequency
FC = V+
Figure 9. Oscillator Frequency Supply Voltage
FC = Open
Figure 10. Oscillator Frequency vs Supply Voltage
FC = V+
Figure 11. Oscillator Frequency vs Temperature
FC = Open
Figure 12. Oscillator Frequency vs Temperature
CAP+
OUT
GND
OSCILLATOR Switch Array
Switch Drivers CAP-
Copyright©2016, Texas Instruments Incorporated
V+
FC
OSC
LV
10
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9 Detailed Description
9.1 Overview
The MAX660 contains four large CMOS switches which are switched in a sequence to invert the input supply
voltage. Energy transfer and storage are provided by external capacitors. Figure 13 shows the voltage
conversion scheme. When S1 and S3 are closed, C1 charges to the supply voltage V+. During this time interval
switches S2 and S4 are open. In the second time interval, S1 and S3 are open and S2 and S4 are closed, C1 is
charging C2. After a number of cycles, the voltage across C2 is pumped to V+. Because the anode of C2 is
connected to ground, the output at the cathode of C2 equals −(V+) assuming no load on C2, no loss in the
switches, and no ESR in the capacitors. In reality, the charge transfer efficiency depends on the switching
frequency, the on-resistance of the switches, and the ESR of the capacitors.
Figure 13. Voltage Inverting Principle
9.2 Functional Block Diagram
11
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9.3 Feature Description
The internal oscillator frequency can be selected using the frequency control (FC) pin. When FC is open, the
oscillator frequency is 10 kHz; when FC is connected to V+, the frequency increases to 80 kHz. A higher
oscillator frequency allows use of smaller capacitors for equivalent output resistance and ripple, but increases the
typical supply current from 0.12 mA to 1 mA. The oscillator frequency can be lowered by adding an external
capacitor between OSC and GND. (See Typical Characteristics.) Also, in the inverter mode, an external clock
that swings within 100 mV of V+ and GND can be used to drive OSC. Any CMOS logic gate is suitable for driving
OSC. LV must be grounded when driving OSC. The maximum external clock frequency is limited to 150 kHz.
The switching frequency of the converter (also called the charge-pump frequency) is half of the oscillator
frequency.
NOTE
OSC cannot be driven by an external clock in the voltage-doubling mode.
Table 1. MAX660 Oscillator Frequency Selection
FC OSC OSCILLATOR
Open Open 10 kHz
V+ Open 80 kHz
Open or V+ External capacitor See Typical Characteristics
N/A External clock (inverter mode only) External clock frequency
9.4 Device Functional Modes
When V+ is applied to the MAX660, the device becomes enabled and operates in whichever configuration the
device is placed (inverter, doubler, etc.).
12
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10 Application and Implementation
NOTE
Information in the following applications sections is not part of the TI component
specification, and TI does not warrant its accuracy or completeness. TI’s customers are
responsible for determining suitability of components for their purposes. Customers should
validate and test their design implementation to confirm system functionality.
10.1 Application Information
The MAX660 CMOS charge-pump voltage converter is a versatile, unregulated switched-capacitor inverter or
doubler. Operating from a wide 1.5-V to 5.5-V supply voltage, the MAX660 uses two low-cost capacitors to
provide 100 mA of output current without the cost, size, and EMI related to inductor-based converters. With an
operating current of only 120 µA and operating efficiency greater than 90% at most loads, the MAX660 provides
ideal performance for battery-powered systems. MAX660 devices can be operated directly in parallel to lower
output impedance, thus providing more current at a given voltage.
10.2 Typical Applications
10.2.1 Voltage Inverter
Figure 14. MAX660 Voltage Inverter
10.2.1.1 Design Requirements
For typical switched capacitor applications, use the parameters in Table 2:
Table 2. Design Parameters
DESIGN PARAMETER EXAMPLE VALUE
Input voltage 5.5 V (maximum)
Negative output voltage –1.5 V to –5.5 V
Output current 100 mA
10.2.1.2 Detailed Design Procedure
The main application of MAX660 is to generate a negative supply voltage. The voltage inverter circuit uses only
two external capacitors as shown in the Figure 14. The range of the input supply voltage is 1.5 V to 5.5 V. For a
supply voltage less than 3.5 V, the LV pin must be connected to ground to bypass the internal regulator circuitry.
This gives the best performance in low-voltage applications. If the supply voltage is greater than 3.5 V, LV may
be connected to ground or left open. The choice of leaving LV open simplifies the direct substitution of the
MAX660 for the LMC7660 switched capacitor voltage converter.
The output characteristics of this circuit can be approximated by an ideal voltage source in series with a resistor.
The voltage source equals −(V+). The output resistance Rout is a function of the ON resistance of the internal
MOS switches, the oscillator frequency, and the capacitance and ESR of C1and C2. A good approximation is:
13
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where
• RSW is the sum of the ON resistance of the internal MOS switches shown in Figure 13. (1)
High-value, low-ESR capacitors reduce the output resistance. Instead of increasing the capacitance, the
oscillator frequency can be increased to reduce the 2/(ƒOSCc × C1) term. Once this term is trivial compared with
RSW and ESRs, further increase to oscillator frequency and capacitance become ineffective. The peak-to-peak
output voltage ripple is determined by the oscillator frequency, and the capacitance and ESR of the output
capacitor C2:
(2)
Again, using a low-ESR capacitor results in lower ripple.
10.2.1.2.1 Capacitor Selection
The output resistance and ripple voltage are dependent on the capacitance and ESR values of the external
capacitors. The output voltage drop is the load current times the output resistance, and the power efficiency is
shown in Equation 3:
where
• IQ(V+) is the quiescent power loss of the device
• IL2ROUT is the conversion loss associated with the switch on-resistance, the two external capacitors and their
ESRs (3)
Because the switching current charging and discharging C1 is approximately twice that of the output current, the
effect of the ESR of the pumping capacitor C1 is multiplied by four in the output resistance. The output capacitor
C2 is charging and discharging at a current approximately equal to the output current; therefore, its ESR only
counts once in the output resistance. However, the ESR of C2 directly affects the output voltage ripple.
Therefore, TI recommends low-ESR capacitors (Table 3) for both capacitors to maximize efficiency, reduce the
output voltage drop and voltage ripple. For convenience, C1 and C2 are usually chosen to be the same. The
output resistance varies with the oscillator frequency and the capacitors. In Figure 15, the output resistance vs
oscillator frequency curves are drawn for three different tantalum capacitors. At very low frequency range,
capacitance plays the most important role in determining the output resistance. Once the frequency is increased
to some point (such as 20 kHz for the 150-μF capacitors), the output resistance is dominated by the ON
resistance of the internal switches and the ESRs of the external capacitors. A low-value, smaller size capacitor
usually has a higher ESR compared with a larger size capacitor of the same type. For lower ESR, use ceramic
capacitors.
Figure 15. Output Source Resistance vs Oscillator Frequency
14
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Table 3. Low-ESR Capacitor Manufacturers
MANUFACTURER CAPACITOR TYPE
Nichicon Corp. PM, PJ series, through-hole aluminum electrolytic
AVX Corp. TPS series, surface-mount tantalum
Vishay Sprague 593D, 594D, 595D series, surface-mount tantalum
Sanyo OS-CON series, through-hole aluminum electrolytic
10.2.1.2.2 Paralleling Devices
Any number of MAX660 devices can be paralleled to reduce the output resistance. Each device must have its
own pumping capacitor C1, while only one output capacitor COUT is required as shown in Figure 16. The
composite output resistance is:
ROUT = ROUT of each MAX660 / Number of Devices (4)
Figure 16. Lowering Output Resistance by Paralleling Devices
10.2.1.2.3 Cascading Devices
Cascading the MAX660s is an easy way to produce a greater negative voltage (as shown in Figure 17). If n is
the integer representing the number of devices cascaded, the unloaded output voltage Vout is (−nVin). The
effective output resistance is equal to the weighted sum of each individual device:
(5)
A three-stage cascade circuit shown in Figure 18 generates −3 Vin, from Vin.
Cascading is also possible when devices are operating in doubling mode. In Figure 19, two devices are
cascaded to generate 3 VIN.
An example of using the circuit in Figure 18 or Figure 19 is generating +15 V or −15 V from a +5-V input.
NOTE
The number of n is practically limited because the increasing of n significantly reduces the
efficiency and increases the output resistance and output voltage ripple.
16
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10.2.1.2.4 Regulating Output Voltage
Output of the MAX660 can be regulated by use of a low-dropout regulator (such as LP2951). The whole
converter is depicted in Figure 20. This converter can give a regulated output from −1.5 V to −5.5 V by choosing
the proper resistor ratio:
(6)
The error flag on pin 5 of the LP2951 goes low when the regulated output at pin 4 drops by about 5%. The
LP2951 can be shut down by taking pin 3 high.
Figure 20. Combining MAX660 With LP2951 to Make a Negative Regulator
As shown in Figure 21 by operating MAX660 in voltage doubling mode and adding a linear regulator (such as
LP2981) at the output, the user can get +5-V output from an input as low as +3 V.
Figure 21. Generating +5 V From +3-V Input Voltage
17
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10.2.1.3 Application Curves
Figure 22. Efficiency vs Load Current Figure 23. Efficiency vs Oscillator Frequency
10.2.2 Positive Voltage Doubler
Figure 24. MAX660 Voltage Doubler
10.2.2.1 Design Requirements
The MAX660 can operate as a positive voltage doubler (as shown in the Figure 24). The doubling function is
achieved by reversing some of the connections to the device. The input voltage is applied to the GND pin with an
allowable voltage from 2.5 V to 5.5 V. The V+ pin is used as the output. The LV pin and OUT pin must be
connected to ground. The OSC pin cannot be driven by an external clock in this operation mode. The unloaded
output voltage is twice of the input voltage and is not reduced by the forward drop of the diode (D1) .
10.2.2.2 Detailed Design Procedure
The Schottky diode D1is only needed for start-up. The internal oscillator circuit uses the V+ pin and the LV pin
(connected to ground in the voltage doubler circuit) as its power rails. Voltage across V+ and LV must be larger
than 1.5 V to ensure the operation of the oscillator. During start-up, D1is used to charge up the voltage at V+ pin
to start the oscillator; also, it protects the device from turning on its own parasitic diode and potentially latching
up. Therefore, the Schottky diode D1must have enough current carrying capability to charge the output capacitor
at start-up, as well as a low forward voltage to prevent the internal parasitic diode from turning on. A Schottky
diode like 1N5817 can be used for most applications. If the input voltage ramp is less than 10V/ms, a smaller
Schottky diode like MBR0520LT1 can be used to reduce the circuit size.
18
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10.3 Split V+ in Half
Another interesting application shown in Figure 25 is to use the MAX660 as a precision voltage divider. Because
the off-voltage across each switch equals VIN/2, the input voltage can be raised to 11 V.
Figure 25. Splitting VIN in Half
11 Power Supply Recommendations
The MAX660 is designed to operate from as an inverter over an input voltage supply range between 1.5 V and
5.5 V when the LV pin is grounded. This input supply must be well regulated and capable to supply the required
input current. If the input supply is located far from the MAX660 additional bulk capacitance may be required in
addition to the ceramic bypass capacitors.
FC
CAP+
GND
CAP-
V+
OSC
LV
OUT
19
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12 Layout
12.1 Layout Guidelines
The high switching frequency and large switching currents of the MAX660 make the choice of layout important.
The following steps should be used as a reference to ensure the device is stable and maintains proper LED
current regulation across its intended operating voltage and current range:
• Place CIN on the top layer (same layer as the MAX60) and as close as possible to the device. Connecting the
input capacitor through short, wide traces to both the V+ and GND pins reduces the inductive voltage spikes
that occur during switching which can corrupt the V+ line.
• Place COUT on the top layer (same layer as the MAX660) and as close as possible to the OUT and GND pin.
The returns for both CIN and COUT must come together at one point, as close as possible to the GND pin.
Connecting COUT through short, wide traces reduce the series inductance on the OUT and GND pins that can
corrupt the VOUT and GND lines and cause excessive noise in the device and surrounding circuitry.
• Place C1on the top layer (same layer as the MAX660) and as close as possible to the device. Connect the
flying capacitor through short, wide traces to both the CAP+ and CAP– pins.
12.2 Layout Example
Figure 26. MAX660 Layout Example
20
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13 Device and Documentation Support
13.1 Device Support
13.1.1 Third-Party Products Disclaimer
TI'S PUBLICATION OF INFORMATION REGARDING THIRD-PARTY PRODUCTS OR SERVICES DOES NOT
CONSTITUTE AN ENDORSEMENT REGARDING THE SUITABILITY OF SUCH PRODUCTS OR SERVICES
OR A WARRANTY, REPRESENTATION OR ENDORSEMENT OF SUCH PRODUCTS OR SERVICES, EITHER
ALONE OR IN COMBINATION WITH ANY TI PRODUCT OR SERVICE.
13.2 Receiving Notification of Documentation Updates
To receive notification of documentation updates, navigate to the device product folder on ti.com. In the upper
right corner, click on Alert me to register and receive a weekly digest of any product information that has
changed. For change details, review the revision history included in any revised document.
13.3 Community Resources
The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective
contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of
Use.
TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration
among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help
solve problems with fellow engineers.
Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and
contact information for technical support.
13.4 Trademarks
E2E is a trademark of Texas Instruments.
All other trademarks are the property of their respective owners.
13.5 Electrostatic Discharge Caution
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more
susceptible to damage because very small parametric changes could cause the device not to meet its published specifications.
13.6 Glossary
SLYZ022 —TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
14 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the most
current data available for the designated devices. This data is subject to change without notice and revision of
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.
PACKAGE OPTION ADDENDUM
www.ti.com 6-Feb-2020
Addendum-Page 1
PACKAGING INFORMATION
Orderable Device Status
(1)
Package Type Package
Drawing Pins Package
Qty Eco Plan
(2)
Lead/Ball Finish
(6)
MSL Peak Temp
(3)
Op Temp (°C) Device Marking
(4/5)
Samples
MAX660M NRND SOIC D 8 95 TBD Call TI Call TI MAX
660M
MAX660M/NOPB ACTIVE SOIC D 8 95 Green (RoHS
& no Sb/Br) SN Level-1-260C-UNLIM -40 to 85 MAX
660M
MAX660MX/NOPB ACTIVE SOIC D 8 2500 Green (RoHS
& no Sb/Br) SN Level-1-260C-UNLIM -40 to 85 MAX
660M
(1) The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based
flame retardants must also meet the <=1000ppm threshold requirement.
(3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
(5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
(6) Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish
value exceeds the maximum column width.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
PACKAGE OPTION ADDENDUM
www.ti.com 6-Feb-2020
Addendum-Page 2
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device Package
Type Package
Drawing Pins SPQ Reel
Diameter
(mm)
Reel
Width
W1 (mm)
A0
(mm) B0
(mm) K0
(mm) P1
(mm) W
(mm) Pin1
Quadrant
MAX660MX/NOPB SOIC D 8 2500 330.0 12.4 6.5 5.4 2.0 8.0 12.0 Q1
PACKAGE MATERIALS INFORMATION
www.ti.com 1-Feb-2016
Pack Materials-Page 1
*All dimensions are nominal
Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm)
MAX660MX/NOPB SOIC D 8 2500 367.0 367.0 35.0
PACKAGE MATERIALS INFORMATION
www.ti.com 1-Feb-2016
Pack Materials-Page 2
www.ti.com
PACKAGE OUTLINE
C
.228-.244 TYP
[5.80-6.19]
.069 MAX
[1.75]
6X .050
[1.27]
8X .012-.020
[0.31-0.51]
2X
.150
[3.81]
.005-.010 TYP
[0.13-0.25]
0 - 8 .004-.010
[0.11-0.25]
.010
[0.25]
.016-.050
[0.41-1.27]
4X (0 -15 )
A
.189-.197
[4.81-5.00]
NOTE 3
B .150-.157
[3.81-3.98]
NOTE 4
4X (0 -15 )
(.041)
[1.04]
SOIC - 1.75 mm max heightD0008A
SMALL OUTLINE INTEGRATED CIRCUIT
4214825/C 02/2019
NOTES:
1. Linear dimensions are in inches [millimeters]. Dimensions in parenthesis are for reference only. Controlling dimensions are in inches.
Dimensioning and tolerancing per ASME Y14.5M.
2. This drawing is subject to change without notice.
3. This dimension does not include mold flash, protrusions, or gate burrs. Mold flash, protrusions, or gate burrs shall not
exceed .006 [0.15] per side.
4. This dimension does not include interlead flash.
5. Reference JEDEC registration MS-012, variation AA.
18
.010 [0.25] C A B
5
4
PIN 1 ID AREA
SEATING PLANE
.004 [0.1] C
SEE DETAIL A
DETAIL A
TYPICAL
SCALE 2.800
www.ti.com
EXAMPLE BOARD LAYOUT
.0028 MAX
[0.07]
ALL AROUND
.0028 MIN
[0.07]
ALL AROUND
(.213)
[5.4]
6X (.050 )
[1.27]
8X (.061 )
[1.55]
8X (.024)
[0.6]
(R.002 ) TYP
[0.05]
SOIC - 1.75 mm max heightD0008A
SMALL OUTLINE INTEGRATED CIRCUIT
4214825/C 02/2019
NOTES: (continued)
6. Publication IPC-7351 may have alternate designs.
7. Solder mask tolerances between and around signal pads can vary based on board fabrication site.
METAL SOLDER MASK
OPENING
NON SOLDER MASK
DEFINED
SOLDER MASK DETAILS
EXPOSED
METAL
OPENING
SOLDER MASK METAL UNDER
SOLDER MASK
SOLDER MASK
DEFINED
EXPOSED
METAL
LAND PATTERN EXAMPLE
EXPOSED METAL SHOWN
SCALE:8X
SYMM
1
45
8
SEE
DETAILS
SYMM
www.ti.com
EXAMPLE STENCIL DESIGN
8X (.061 )
[1.55]
8X (.024)
[0.6]
6X (.050 )
[1.27] (.213)
[5.4]
(R.002 ) TYP
[0.05]
SOIC - 1.75 mm max heightD0008A
SMALL OUTLINE INTEGRATED CIRCUIT
4214825/C 02/2019
NOTES: (continued)
8. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate
design recommendations.
9. Board assembly site may have different recommendations for stencil design.
SOLDER PASTE EXAMPLE
BASED ON .005 INCH [0.125 MM] THICK STENCIL
SCALE:8X
SYMM
SYMM
1
45
8
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