Datasheet

ManualsBrandsMAXIM INTEGRATED ManualsPMICsPMIC - DC/DC voltage regulator Switched-capacitor voltage converter uMAX 8

AVAILABLE

Functional Diagrams

Pin Configurations appear at end of data sheet.

Functional Diagrams continued at end of data sheet.

UCSP is a trademark of Maxim Integrated Products, Inc.

For pricing, delivery, and

ordering information, please contact Maxim Direct

at 1-888-629-4642, or visit Maxim’s website at www.maximintegrated.com.

_______________General Description

The MAX1044 and ICL7660 are monolithic, CMOS

switched-capacitor voltage converters that invert, dou-

ble, divide, or multiply a positive input voltage. They are

pin compatible with the industry-standard ICL7660 and

LTC1044. Operation is guaranteed from 1.5V to 10V with

no external diode over the full temperature range. They

deliver 10mA with a 0.5V output drop. The MAX1044

has a BOOST pin that raises the oscillator frequency

above the audio band and reduces external capacitor

size requirements.

The MAX1044/ICL7660 combine low quiescent current

and high efficiency. Oscillator control circuitry and four

power MOSFET switches are included on-chip.

Applications include generating a -5V supply from a

+5V logic supply to power analog circuitry. For applica-

tions requiring more power, the MAX660 delivers up to

100mA with a voltage drop of less than 0.65V.

________________________Applications

-5V Supply from +5V Logic Supply

Personal Communications Equipment

Portable Telephones

Op-Amp Power Supplies

EIA/TIA-232E and EIA/TIA-562 Power Supplies

Data-Acquisition Systems

Hand-Held Instruments

Panel Meters

____________________________Features

♦ Miniature µMAX Package

♦ 1.5V to 10.0V Operating Supply Voltage Range

♦ 98% Typical Power-Conversion Efficiency

♦ Invert, Double, Divide, or Multiply Input Voltages

♦ BOOST Pin Increases Switching Frequencies

(MAX1044)

♦ No-Load Supply Current: 200µA Max at 5V

♦ No External Diode Required for Higher-Voltage

Operation

______________Ordering Information

Ordering Information continued at end of data sheet.

* Contact factory for dice specifications.

Switched-Capacitor Voltage Converters

MAX1044

ICL7660

CAP-

GND

CAP+

(N.C.) BOOST

OUT

OSC

V+

TOP VIEW

( ) ARE FOR ICL7660

DIP/SO/µMAX

TO-99

ICL7660

N.C.

CAP+

GND

CAP-

OUT

OSC

V+ AND CASE

_________________Pin Configurations

NEGATIVE VOLTAGE CONVERTER

CAP+

CAP-

V+

OUT

GND

INPUT

SUPPLY

VOLTAGE

NEGATIVE

OUTPUT

VOLTAGE

MAX1044

ICL7660

__________Typical Operating Circuit

Dice*

8 SO

8 Plastic DIP

PIN-PACKAGETEMP. RANGE

0°C to +70°C

0°C to +70°CMAX1044C/D

MAX1044CSA

MAX1044CPA

PART

8 Plastic DIP-40°C to +85°CMAX1044EPA

19-4667; Rev 1; 7/94

MAX1044/ICL7660

Summary of content (13 pages)

PAGE 1
MAX1044/ICL7660 LE AVAILAB Switched-Capacitor Voltage Converters _______________General Description The MAX1044 and ICL7660 are monolithic, CMOS switched-capacitor voltage converters that invert, double, divide, or multiply a positive input voltage. They are pin compatible with the industry-standard ICL7660 and LTC1044. Operation is guaranteed from 1.5V to 10V with no external diode over the full temperature range. They deliver 10mA with a 0.5V output drop.
PAGE 2
MAX1044/ICL7660 Switched-Capacitor Voltage Converters ABSOLUTE MAXIMUM RATINGS Supply Voltage (V+ to GND, or GND to VOUT)....................10.5V Input Voltage on Pins 1, 6, and 7 .........-0.3V ≤ VIN ≤ (V+ + 0.3V) LV Input Current ..................................................................20µA Output Short-Circuit Duration (V+ ≤ 5.5V)..................Continuous Continuous Power Dissipation (TA = +70°C) Plastic DIP (derate 9.09mW/°C above +70°C) ............727mW SO (derate 5.88mW/°C above +70°C) .
PAGE 3
MAX1044/ICL7660 Switched-Capacitor Voltage Converters __________________________________________Typical Operating Characteristics (V+ = 5V; CBYPASS = 0.1µF; C1 = C2 = 10µF; LV = open; OSC = open; TA = +25°C; unless otherwise noted.) 150 C V+ = 2V LV = GND -0.5 100 50 A OUTPUT RIPPLE 0 1 2 3 4 5 6 7 8 9 C C -1.
PAGE 4
MAX1044/ICL7660 Switched-Capacitor Voltage Converters ____________________________Typical Operating Characteristics (continued) (V+ = 5V; CBYPASS = 0.1µF; C1 = C2 = 10µF; LV = open; OSC = open; TA = +25°C; unless otherwise noted.) OSCILLATOR FREQUENCY vs. TEMPERATURE QUIESCENT CURRENT vs.
PAGE 5
MAX1044/ICL7660 Switched-Capacitor Voltage Converters _____________________________________________________________ Pin Description PIN NAME FUNCTION BOOST (MAX1044) Frequency Boost. Connecting BOOST to V+ increases the oscillator frequency by a factor of six. When the oscillator is driven externally, BOOST has no effect and should be left open. N.C. (ICL7660) No Connection 1 2 CAP+ Connection to positive terminal of Charge-Pump Capacitor 3 GND Ground.
PAGE 6
MAX1044/ICL7660 Switched-Capacitor Voltage Converters S1 current is: I = f x ΔQ = f x C1(V+ - VOUT). Rewriting this equation in Ohm’s law form defines an equivalent resistance synthesized by the switched-capacitor circuit where: S2 V+ (V+ - VOUT ) 1 / (f x C1) and 1 REQUIV = f x C1 I= C1 S3 C2 S4 VOUT = -(V+) where f is one-half the oscillator frequency. This resistance is a major component of the output impedance of switched-capacitor circuits like the MAX1044/ICL7660.
PAGE 7
MAX1044/ICL7660 Switched-Capacitor Voltage Converters CONNECTION FROM V+ TO BOOST C1 10µF 2 V+ 8 1 MAX1044 ICL7660 7 3 6 4 5 VOUT = -(V+) 1 V+ 8 CBYPASS * C2 10µF 2 MAX1044 7 10µF 3 6 4 5 COSC VOUT = -(V+) 10µF *REQUIRED FOR V+ < 3.5V Figure 5. Basic Negative Voltage Converter Figure 6. Negative Voltage Converter with COSC and BOOST and allow operation down to 1.5V.
PAGE 8
MAX1044/ICL7660 Switched-Capacitor Voltage Converters V+ 1 2 10µF 10kΩ REQUIRED FOR TTL CMOS or V+ TTL GATE 8 MAX1044 ICL7660 7 3 6 4 5 VOUT = -(V+) 10µF switching noise and EMI may be generated. To reduce these effects: 1) Power the MAX1044/ICL7600 from a low-impedance source. 2) Add a power-supply bypass capacitor with low effective series resistance (ESR) close to the IC between the V+ and ground pins. 3) Shorten traces between the IC and the charge-pump capacitors.
PAGE 9
MAX1044/ICL7660 Switched-Capacitor Voltage Converters The first term is the effective resistance from the switched-capacitor circuit. Conversion losses occur during the transfer of charge between capacitors C1 and C2 when there is a voltage difference between them. The power loss is: ⎡1 2 PCONV.LOSS = ⎢ C1 ⎛ (V+ ) 2 − VOUT ⎞ + ⎝ ⎠ ⎣2 ⎤ 1 2 C2 ⎛ VRIPPLE − 2VOUT VRIPPLE ⎞ ⎥ x fOSC / 2 ⎝ ⎠⎦ 2 Increasing Efficiency Efficiency can be improved by lowering output voltage ripple and output impedance.
PAGE 10
MAX1044/ICL7660 Switched-Capacitor Voltage Converters V+ V+ C1 10µF 1 8 1 2 7 2 3 MAX1044 ICL7660 LV 4 3 C1 6 MAX1044 ICL7660 7 VOUT = -(V+) C3 LV 4 5 8 6 5 VOUT = 2(V+) - 2VD VOUT = 1 V+ 2 C2 10µF C2 Figure 10. Voltage Divider Figure 11. Combined Positive and Negative Converter capacitors for the doubled positive voltage. This circuit has higher output impedances resulting from the use of a common charge-pump driver.
PAGE 11
MAX1044/ICL7660 Switched-Capacitor Voltage Converters Paralleling Devices 1 C1 V+ 8 2 7 MAX1044 ICL7660 3 Paralleling multiple MAX1044/ICL7660s reduces output resistance and increases current capability. As illustrated in Figure 13, each device requires its own pump capacitor C1, but the reservoir capacitor C2 serves all devices.
PAGE 12
MAX1044/ICL7660 Switched-Capacitor Voltage Converters __________________________________________________________Chip Topographies MAX1044 GND CAP+ ICL7660 BOOST V+ 0.084" (2.1mm) CAP+ 0.076" (1.930mm) GND OSC CAPCAPV+ LV V OUT V OUT LV OSC 0.060" (1.5mm) 0.076" (1.930mm) TRANSISTOR COUNT: 72 SUBSTRATE CONNECTED TO V+ TRANSISTOR COUNT: 71 SUBSTRATE CONNECTED TO V+ ________________________________________________________Package Information DIM E A A1 B C D E e H L α H INCHES MAX MIN 0.044 0.
PAGE 13
MAX1044/ICL7660 Switched-Capacitor Voltage Converters 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. 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.