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LD2985BM18R

Low-Dropout Linear Voltage Regulator

The LD2985BM18R is a low-dropout linear voltage regulator from STMicroelectronics. View the full LD2985BM18R datasheet below including key specifications, electrical characteristics, absolute maximum ratings.

Official LD2985BM18R datasheet (PDF) — the source this page was extracted from.

Manufacturer

STMicroelectronics

Package

SOT-23-5

LD2985BM18R Key Specifications

ParameterValue
Output Currentup to 150 mA
Output Voltage1.8 V
Dropout Voltage280 mV typ. at 150 mA; 7 mV typ. at 1 mA
Shutdown Currentless than 1 µA typ. (VINH < 0.18 V)
Quiescent Current80 µA typ. at no load; 2 mA typ. at 150 mA
Output Noise Voltage30 µVrms (300 Hz to 50 kHz, CBYP = 10 nF)
Short-Circuit Current400 mA typ.
Operating Input Voltage2.5 V to 16 V
Output Voltage Accuracy1.755 V to 1.845 V (25 °C); 1.728 V to 1.872 V (-40 to 125 °C)
Inhibit Logic ThresholdsVIL 0.15 V max, VIH 2 V min
Supply Voltage Rejection45 dB typ. (1 kHz)
Recommended Output Capacitor2.2 µF ceramic min. (1.8 to 3.3 V versions)
Operating Junction Temperature-40 °C to 125 °C
Thermal Resistance Junction-Ambient255 °C/W

LD2985BM18R Overview

Part: LD2985 — STMicroelectronics

Type: Fixed Output Voltage Regulator (LDO)

Description: A 150 mA fixed output voltage regulator with very low dropout voltage (280 mV at 150 mA load) and low quiescent current (80 μA typ. at no load), featuring logic controlled electronic shutdown and low output noise voltage (30 μVrms).

Operating Conditions:

  • Supply voltage: 2.5–16 V
  • Operating temperature: -40 to 125 °C
  • Output voltage: 1.8, 2.5, 2.8, 3, 3.1, 3.3, 5 V

Absolute Maximum Ratings:

  • Max supply voltage: 16 V
  • Max continuous current: Internally limited
  • Max storage temperature: 150 °C
  • Max operating junction temperature: 125 °C

Key Specs:

  • Dropout voltage: 280 mV (typ. at 150 mA)
  • Quiescent current: 80 μA (typ. at I O = 0)
  • Output noise voltage: 30 μVrms (typ. B = 300 Hz to 50 kHz, C BYP = 0.01 μF, C O = 10 μF)
  • Load regulation: 20 mV (max. I O = 1 to 150 mA, T J = -40 to 125 °C)
  • Line regulation: 0.003 %/V I (typ. V I = V O + 1 V to 16 V, I O = 1 mA)
  • Short-circuit current: 400 mA (typ. R L = 0)
  • Inhibit input logic low: 0.15 V (max. T J = -40 to 125 °C)

Features:

  • Very low dropout voltage (280 mV at 150 mA and 7 mV at 1 mA load)
  • Very low quiescent current (2 mA typ. at 150 mA load and 80 μA at no load)
  • Output current up to 150 mA
  • Logic controlled electronic shutdown
  • Output voltage of 1.8, 2.5, 2.8, 3, 3.1, 3.3, 5 V
  • Internal current and thermal limit
  • Low output noise voltage 30 μVrms
  • Small package SOT23-5L
  • Temperature range: - 40 °C to 125 °C

Applications:

  • Cellular phone
  • Palmtop laptop computer
  • Personal digital assistant (PDA)
  • Personal stereo
  • Camcorder and camera

Package:

  • SOT23-5L

LD2985BM18R Features

  • Very low dropout voltage (280 mV at 150 mA and 7 mV at 1 mA load)
  • Very low quiescent current (2 mA typ. at 150 mA load and 80 μA at no load)
  • Output current up to 150 mA
  • Logic controlled electronic shutdown
  • Output voltage of 1.8, 2.5, 2.8, 3, 3.1, 3.3, 5 V
  • Internal current and thermal limit
  • Low output noise voltage 30 μVrms
  • Small package SOT23-5L
  • Temperature range: - 40 °C to 125 °C

LD2985BM18R Pin Configuration

Figure 2. Pin connections (top view)

Table 2. Pin description

Pin n°SymbolName and function
1INInput port
2GNDGround pin
3INHIBITControl switch ON/OFF. Inhibit is not internally pulled-up; it cannot be left floating. Disable the device when connected to GND or to a positive voltage less than 0.18 V
4BypassBypass pin: capacitor to be connected to GND in order to improve the thermal noise performance
5OUTOutput port

Table 3. Thermal data

SymbolParameterValueUnit
R thJCThermal resistance junction-case81°C/W
R thJAThermal resistance junction-ambient255°C/W

Table 3. Thermal data

LD2985BM18R Electrical Characteristics

T J = 25 °C, V I = V O + 1 V, I O = 50 mA, V INH = 2 V, C I = C O = 1 μF, unless otherwise specified.

Table 5. Electrical characteristics

SymbolParameterTest conditionsMin.Typ.Max.Unit
V OPOperating input voltage2.516V
V OOutput voltageV I = 2.8 V1.7551.81.845V
V OOutput voltageI O = 1 to 150 mA1.7461.854V
V OOutput voltageI O = 1 to 150 mA, T J = -40 to 125 °C1.7281.872V
V OOutput voltageV I = 3.5 V2.4372.52.562V
V OOutput voltageI O = 1 to 150 mA2.4252.575V
V OOutput voltageI O = 1 to 150 mA, T J = -40 to 125 °C2.42.6V
V OOutput voltageV I = 3.8 V2.732.82.87V
V OOutput voltageI O = 1 to 150 mA2.7162.884V
V OOutput voltageI O = 1 to 150 mA, T J = -40 to 125 °C2.6882.912V
V OOutput voltageV I = 4.0 V2.92533.075V
V OOutput voltageI O = 1 to 150 mA2.913.09V
V OOutput voltageI O = 1 to 150 mA, T J = -40 to 125 °C2.883.12V
V OOutput voltageV I = 4.1 V3.0233.13.177V
V OOutput voltageI O = 1 to 150 mA3.0073.193V
V OOutput voltageI O = 1 to 150 mA, T J = -40 to 125 °C2.9763.224V
V OOutput voltageV I = 4.3 V3.2183.33.382V
V OOutput voltageI O = 1 to 150 mA3.2013.399V
V OOutput voltageI O = 1 to 150 mA, T J = -40 to 125 °C3.1683.432V
V OLoad regulationI O = 1 to 150 mA, T J = -40 to 125 °C20mV
V OOutput voltageV I = 6.0 V4.87555.125V
V OOutput voltageI O = 1 to 150 mA4.855.15V
V OOutput voltageI O = 1 to 150 mA, T J = -40 to 125 °C4.85.2V
I SCShort-circuit currentR L = 0400mA
∆ V O / ∆ V ILine regulationV I = V O + 1 V to 16 V, I O = 1 mA0.0030.014%/V I
∆ V O / ∆ V ILine regulationV I = V O + 1 V to 16 V, I O = 1 mA, T J = -40 to 125 °C0.032%/V I

Table 5. Electrical characteristics

Table 5. Electrical characteristics (continued)

SymbolParameterTest conditionsMin.Typ.Max.Unit
V DROPDropout voltageI O = 013mV
V DROPI O = 0, T J = -40 to 125 °C5mV
V DROPI O = 1 mA710mV
V DROPI O = 1 mA, T J = -40 to 125 °C15mV
V DROPI O = 10 mA4060mV
V DROPI O = 10 mA, T J = -40 to 125 °C90mV
V DROPI O = 50 mA120150mV
V DROPI O = 50 mA, T J = -40 to 125 °C225mV
V DROPI O = 150 mA280350mV
V DROPI O = 150 mA, T J = -40 to 125 °C575mV
I QI O = 080100μA
I QI O = 0, T J = -40 to 125 °C150μA
I QI O = 1 mA100150μA
I QI O = 1 mA, T J = -40 to 125 °C200μA
I QQuiescent currentI O = 10 mA200300μA
I QON MODEI O = 10 mA, T J = -40 to 125 °C400μA
I QI O = 50 mA600900μA
I QI O = 50 mA, T J = -40 to 125 °C1200μA
I QI O = 150 mA20003000μA
I QI O = 150 mA, T J = -40 to 125 °C4000μA
OFF MODEV INH <0.18 V0μA
OFF MODEV INH <0.18 V, T J = -40 to 125 °C2μA
SVRSupply voltage rejectionC BYP = 0.01 μF, C O = 10 μF, f = 1 kHz45dB
V ILInhibit input logic lowT J = -40 to 125 °C0.15V
V IHInhibit input logic highT J = -40 to 125 °C2V
I INHInhibit input currentV INH = 0 V, T J = -40 to 125 °C515μA
I INHV INH = 5 V, T J = -40 to 125 °C0-1μA
e NOutput noise voltageB = 300 Hz to 50 kHz, C BYP = 0.01 μF, C O = 10 μF30μV

Table 5. Electrical characteristics (continued)

LD2985BM18R Absolute Maximum Ratings

Table 4. Absolute maximum ratings

SymbolParameterValueUnit
V IDC input voltage-0.3 to 16V
V INHINHIBIT input voltage-0.3 to 16V
I OOutput currentInternally limited
P DPower dissipationInternally limited
T STGStorage temperature range-65 to 150°C
T OPOperating junction temperature range-40 to 125°C

Note: Absolute maximum ratings are those values beyond which damage to the device may occur. Functional operation under these condition is not implied.

Table 4. Absolute maximum ratings

LD2985BM18R Package Information

In order to meet environmental requirements, ST offers these devices in different grades of ECOPACK packages, depending on their level of environmental compliance. ECOPACK specifications, grade definitions and product status are available at: www.st.com. ECOPACK is an ST trademark.

Figure 18. SOT23-5L package outline

Table 6. SOT23-5L mechanical data

Dim.mmmmmm
Dim.Min.Typ.Max.
A0.901.45
A100.15
A20.901.30
b0.300.50
c0.090.20
D2.95
E1.60
e0.95
H2.80
L0.300.60
θ08

Figure 19. SOT23-5L package outlineSOT23-5L recommended footprint (dimensions in mm)

Table 6. SOT23-5L mechanical data

Variants on the same datasheet

These parts have exact links to the same datasheet. They are candidates to compare, not verified drop-in replacements; check package, pinout and electrical limits.

Part NumberManufacturerPackage
LD2985BM25RSTMicroelectronicsSOT23-5L
LD2985BM28RSTMicroelectronicsSOT23-5
LD2985BM30RSTMicroelectronicsSOT23-5
LD2985BM31RSTMicroelectronicsSOT23-5L

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