LD2985

Low Dropout Linear Regulator

The LD2985 is a low dropout linear regulator from STMicroelectronics. View the full LD2985 datasheet below including key specifications, electrical characteristics, absolute maximum ratings.

Official LD2985 datasheet (PDF) — the source this page was extracted from.

Manufacturer

STMicroelectronics

LD2985 Key Specifications

Parameter	Value
Output Current	150 mA (max)
Dropout Voltage	280 mV typ at 150 mA, 7 mV typ at 1 mA
Shutdown Current	less than 1 µA (INHIBIT low)
Quiescent Current	80 µA typ at no load, 2 mA typ at 150 mA load
Input Voltage Range	2.5V to 16V
Output Noise Voltage	30 µVrms (CBYP = 10 nF)
Short-Circuit Current	400 mA typ
Output Voltage Options	1.8V, 2.5V, 2.8V, 3.0V, 3.1V, 3.3V, 5.0V
Output Voltage Accuracy	±2.5% (initial, at 25°C)
Inhibit Logic Thresholds	VIL 0.15V max, VIH 2V min
Supply Voltage Rejection	45 dB typ at 1 kHz
Absolute Max Input Voltage	16V
Operating Junction Temperature	-40°C to 125°C
Thermal Resistance Junction-Ambient	255 °C/W

LD2985 Overview

Part: LD2985 — STMicroelectronics

Type: Very Low Drop and Low Noise Voltage Regulator

Description: A 150 mA fixed output voltage regulator with very low dropout voltage (280 mV at 150 mA) and low quiescent current (80 μA at no load), featuring an inhibit function for reduced power consumption and low output noise voltage of 30 μVrms.

Operating Conditions:

Supply voltage: 2.5–16 V
Operating temperature: -40 to 125 °C
Output current: up to 150 mA
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

Key Specs:

Dropout voltage: 280 mV (typ. at I_O = 150 mA, T_J = 25 °C)
Quiescent current: 80 μA (typ. at I_O = 0, T_J = 25 °C)
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)
Inhibit input logic high: 2 V (min. 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

Applications:

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

Package:

SOT23-5L

LD2985 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

LD2985 Pin Configuration

Figure 2. Pin connections (top view)

Table 2. Pin description

Pin n°	Symbol	Name and function
1	IN	Input port
2	GND	Ground pin
3	INHIBIT	Control 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
4	Bypass	Bypass pin: capacitor to be connected to GND in order to improve the thermal noise performance
5	OUT	Output port

Table 3. Thermal data

Symbol	Parameter	Value	Unit
R thJC	Thermal resistance junction-case	81	°C/W
R thJA	Thermal resistance junction-ambient	255	°C/W

Table 3. Thermal data

LD2985 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

Symbol	Parameter	Test conditions	Min.	Typ.	Max.	Unit
V OP	Operating input voltage		2.5		16	V
V O	Output voltage	V I = 2.8 V	1.755	1.8	1.845	V
V O	Output voltage	I O = 1 to 150 mA	1.746		1.854	V
V O	Output voltage	I O = 1 to 150 mA, T J = -40 to 125 °C	1.728		1.872	V
V O	Output voltage	V I = 3.5 V	2.437	2.5	2.562	V
V O	Output voltage	I O = 1 to 150 mA	2.425		2.575	V
V O	Output voltage	I O = 1 to 150 mA, T J = -40 to 125 °C	2.4		2.6	V
V O	Output voltage	V I = 3.8 V	2.73	2.8	2.87	V
V O	Output voltage	I O = 1 to 150 mA	2.716		2.884	V
V O	Output voltage	I O = 1 to 150 mA, T J = -40 to 125 °C	2.688		2.912	V
V O	Output voltage	V I = 4.0 V	2.925	3	3.075	V
V O	Output voltage	I O = 1 to 150 mA	2.91		3.09	V
V O	Output voltage	I O = 1 to 150 mA, T J = -40 to 125 °C	2.88		3.12	V
V O	Output voltage	V I = 4.1 V	3.023	3.1	3.177	V
V O	Output voltage	I O = 1 to 150 mA	3.007		3.193	V
V O	Output voltage	I O = 1 to 150 mA, T J = -40 to 125 °C	2.976		3.224	V
V O	Output voltage	V I = 4.3 V	3.218	3.3	3.382	V
V O	Output voltage	I O = 1 to 150 mA	3.201		3.399	V
V O	Output voltage	I O = 1 to 150 mA, T J = -40 to 125 °C	3.168		3.432	V
V O	Load regulation	I O = 1 to 150 mA, T J = -40 to 125 °C			20	mV
V O	Output voltage	V I = 6.0 V	4.875	5	5.125	V
V O	Output voltage	I O = 1 to 150 mA	4.85		5.15	V
V O	Output voltage	I O = 1 to 150 mA, T J = -40 to 125 °C	4.8		5.2	V
I SC	Short-circuit current	R L = 0		400		mA
∆ V O / ∆ V I	Line regulation	V I = V O + 1 V to 16 V, I O = 1 mA		0.003	0.014	%/V I
∆ V O / ∆ V I	Line regulation	V I = V O + 1 V to 16 V, I O = 1 mA, T J = -40 to 125 °C			0.032	%/V I

Table 5. Electrical characteristics

Table 5. Electrical characteristics (continued)

Symbol	Parameter	Test conditions	Min.	Typ.	Max.	Unit
V DROP	Dropout voltage	I O = 0		1	3	mV
V DROP		I O = 0, T J = -40 to 125 °C			5	mV
V DROP		I O = 1 mA		7	10	mV
V DROP		I O = 1 mA, T J = -40 to 125 °C			15	mV
V DROP		I O = 10 mA		40	60	mV
V DROP		I O = 10 mA, T J = -40 to 125 °C			90	mV
V DROP		I O = 50 mA		120	150	mV
V DROP		I O = 50 mA, T J = -40 to 125 °C			225	mV
V DROP		I O = 150 mA		280	350	mV
V DROP		I O = 150 mA, T J = -40 to 125 °C			575	mV
I Q		I O = 0		80	100	μA
I Q		I O = 0, T J = -40 to 125 °C			150	μA
I Q		I O = 1 mA		100	150	μA
I Q		I O = 1 mA, T J = -40 to 125 °C			200	μA
I Q	Quiescent current	I O = 10 mA		200	300	μA
I Q	ON MODE	I O = 10 mA, T J = -40 to 125 °C			400	μA
I Q		I O = 50 mA		600	900	μA
I Q		I O = 50 mA, T J = -40 to 125 °C			1200	μA
I Q		I O = 150 mA		2000	3000	μA
I Q		I O = 150 mA, T J = -40 to 125 °C			4000	μA
	OFF MODE	V INH <0.18 V		0		μA
	OFF MODE	V INH <0.18 V, T J = -40 to 125 °C			2	μA
SVR	Supply voltage rejection	C BYP = 0.01 μF, C O = 10 μF, f = 1 kHz		45		dB
V IL	Inhibit input logic low	T J = -40 to 125 °C			0.15	V
V IH	Inhibit input logic high	T J = -40 to 125 °C	2			V
I INH	Inhibit input current	V INH = 0 V, T J = -40 to 125 °C		5	15	μA
I INH		V INH = 5 V, T J = -40 to 125 °C		0	-1	μA
e N	Output noise voltage	B = 300 Hz to 50 kHz, C BYP = 0.01 μF, C O = 10 μF		30		μV

Table 5. Electrical characteristics (continued)

LD2985 Absolute Maximum Ratings

Table 4. Absolute maximum ratings

Symbol	Parameter	Value	Unit
V I	DC input voltage	-0.3 to 16	V
V INH	INHIBIT input voltage	-0.3 to 16	V
I O	Output current	Internally limited
P D	Power dissipation	Internally limited
T STG	Storage temperature range	-65 to 150	°C
T OP	Operating 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

LD2985 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.	mm	mm	mm
Dim.	Min.	Typ.	Max.
A	0.90		1.45
A1	0		0.15
A2	0.90		1.30
b	0.30		0.50
c	0.09		0.20
D		2.95
E		1.60
e		0.95
H		2.80
L	0.30		0.60
θ	0		8

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 Number	Manufacturer	Package
LD2985BM18R	STMicroelectronics	SOT-23-5
LD2985BM25R	STMicroelectronics	SOT23-5L
LD2985BM28R	STMicroelectronics	SOT23-5
LD2985BM30R	STMicroelectronics	SOT23-5

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R1191L – Nisshinbo, LDO Regulator
AAT3221IGV-3.3-T1 – Skyworks Solutions, LDO Linear Regulator
AMS1117 – Advanced Monolithic Systems, Low Dropout Voltage Regulator

All Linear Regulators (LDO) datasheets All STMicroelectronics datasheets (808)

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