HOME HOME SELECT DESIGN BUY EXPLORE About Us Support My Profile Search

 Products > Analog - Regulators > SwitchedCapacitor Converters > LM2781

LM2781  Product Folder

Ultra-Low Ripple Switched Capacitor Voltage Inverter
Generic P/N 2781
General
Description
Features Datasheet Package
& Models
Samples
& Pricing
Reliability
Metrics

Parametric Table Parametric Table
Temperature Min (deg C) -40 
Temperature Max (deg C) 85 
Multiple Output Capability No 
On/Off Pin Yes 
Error Flag No 
InputMin Voltage (Volt) 1.80 
InputMax Voltage (Volt) 5.50 
Output Current (mA) 50 
Output Voltage (Volt)
Adjustable Output No 
Switching Frequency (Hz) 210000 
Adj Switch Frequency No 
Sync Pin No 
Efficiency (%) 92 
Inverting Yes 
Step-Up
Step-Down
RegType Switched Capacitor 

Datasheet

TitleSize in KbytesDate
View Online

Download

Receive via Email
LM2781 Ultra-Low Ripple Switched Capacitor Voltage Inverter 162 Kbytes 3-Mar-03 View Online Download Receive via Email

If you have trouble printing or viewing PDF file(s), see Printing Problems.

Package Availability, Models, Samples & Pricing

Part NumberPackageStatusModelsSamples &
Electronic
Orders
Budgetary PricingStd
Pack
Size
Package
Marking
TypePinsMSL/Lead-Free AvailabilityLead
Time
QtySPICEIBISQty$US each
LM2781TPmicroSMD8StatusFull productionN/AN/A24 Hour Samples
Buy Now
1K+$0.53reel
of
250
XV
I 12
5-7 weeks5000
LM2781TPXmicroSMD8StatusFull productionN/AN/A 1K+$0.53reel
of
3000
XV
I 12
5-7 weeks5000

General Description

The LM2781 is a charge pump that inverts an input voltage in the range of 1.8V to 5.5V to the corresponding output voltage of -1.8V to -5.5V. With use of three or four low-cost external ceramic capacitors, the LM2781 can provide up to 50mA of output current.

The LM2781 operates at a 210kHz typical switching frequency to minimize supply current (0.7mA typ.). Two charge pumps operate 180° out of phase to significantly reduce the output voltage ripple compared to that of traditional single-phase charge pump circuits. If larger output ripple can be tolerated, optional capacitor C2 may be omitted to reduce the cost and size of the solution. The LM2781 is available in an 8-pin Micro SMD chip-scale package.

See also: LM2780, a slow clock (12kHz typ) version of this topology with extremely low supply current.

Features

  • Inverts Input Voltage
  • Ultra-Low Voltage Ripple and 8 Typical Output Resistance with Two Flying Capacitors
  • Output Resistance of 18 Using One Flying Capacitor
  • 210kHz (typ.) Switching Frequency
  • 8-pin micro SMD Package (1.4mm × 1.4mm × 0.5mm)

Applications

  • Cellular Phones
  • Pagers
  • PDAs
  • Op-Amp Power Supplies
  • Interface Power Supplies
  • Handheld Instruments

Reliability Metrics

Part Number Process Early Failure Rate - Rejects Sample Size (EFR) PPM * Rel. Rejects Device Hours Long Term Failure Rates (FITS) MTTF
LM2781TPABCD15001020000924003926125054
LM2781TPXABCD15001020000924003926125054

For more information on Reliablitity Metrics, please click here.


[Information as of 15-Jan-2004]