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LD2980ABXX中文资料

July 2008Rev 171/23

LD2980ABxx LD2980Cxx

Ultra low drop voltage regulators compatible

with low ESR inhibit output capacitors

Features

■Stable with low ESR ceramic capacitors ■Ultra low dropout voltage (0.12 V typ. at 50 mA load, 7 mV typ. at 1 mA load)

■Very low quiescent current (80 μA typ. at no load in on mode; max 1 μA in off mode)■Guaranteed output current up to 50 mA ■Logic-controlled electronic shutdown ■Output voltage of 1.8; 3.0; 3.3; 3.6; 5.0 V ■Internal current and thermal limit

■± 0.5% Tolerance output voltage available (A version)

■Output low noise voltage 160 μVRMS ■Temperature range: -40 to 125 °C ■Smallest package SOT23-5L and SOT-89■

Fast dynamic response to line and load changes

Description

The low drop-voltage and the ultra low quiescent current make them suitable for low noise, low power applications and in battery

poweredsystems. The quiescent current in sleep mode is less than 1 μA when the INHIBIT pin is pulled low. A shutdown logic control function is available on pin n° 3 (TTL compatible). This means that when the device is used as local

regulator, it is possible to put a part of the board in standby, decreasing the total power consumption. The LD2980 is designed to work with low ESR ceramic capacitors. T ypical applications are cellular phone, laptop computer, personal digital assistant (PDA), personal stereo, camcorder and camera.

Table 1.

Device summary

Part numbers

AB Version

C Version Output voltage

LD2980CXX18

1.8 V LD2980ABXX30 3.0 V LD2980ABXX33LD2980CXX33 3.3 V LD2980ABXX36LD2980CXX36 3.6 V LD2980ABXX50

LD2980CXX50

5.0 V

https://www.wendangku.net/doc/e614164417.html,

LD2980ABxx - LD2980Cxx

Contents

1Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2Pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 3Maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 4Typical application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 5Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 6Typical performance characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

7Application notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

7.1External capacitors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

7.2Input capacitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

7.3Output capacitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

7.4Important . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

7.5Inhibit input operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

7.6Reverse current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 8Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 9Order codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 10Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

2/23

LD2980ABxx - LD2980Cxx Diagram 1 Diagram

3/23

Pin configuration

LD2980ABxx - LD2980Cxx

4/23

2

Pin configuration

Table 2.

Pin description

Pin n°SOT23-5L

Pin n°SOT -89Symbol Name and Function

13V IN Input port 22

GND Ground pin

3INHIBIT 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 4NC

Not connected 5

1

V OUT

Output port

Table 3.

Thermal data

Symbol Parameter

SOT23-5L

SOT-89Unit R thJC Thermal resistance junction-case 8115°C/W R thJA

Thermal resistance junction-ambient

255

110

°C/W

LD2980ABxx - LD2980Cxx

Maximum ratings

5/23

3 Maximum ratings

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

Symbol Parameter

Value Unit V I DC input voltage -0.3 to 16V V INH INHIBIT input voltage -0.3 to 16V

I O Output current Internally limited P D Power dissipation

Internally limited T STG Storage temperature range

-55 to 150°C T OP

Operating junction temperature range

-40 to 125

°C

Typical application LD2980ABxx - LD2980Cxx 4 Typical application

Note:Inhibit pin is not internally pulled-up then it must not be left floating. Disable the device when connected to GND or to a positive voltage less than 0.18 V.

6/23

LD2980ABxx - LD2980Cxx

Electrical characteristics

7/23

5 Electrical characteristics

Table 5.

Electrical characteristics for LD2980AB (T J = 25 °C, V I = V O(NOM) +1 V , C I = 1 μF(X7R),

C O = 2.2 μF (X7R), I O = 1 mA, V INH = 2 V , unless otherwise specified).

Symbol Parameter

Test conditions

Min.Typ.

Max.Unit V OP Operating input voltage

2.516V

V O

Output voltage

I O = 1 mA

2.487 2.5 2.513V I O = 1 to 50 mA

2.481 2.519I O = 1 to 50 mA, T J = -40 to 125°C 2.437 2.562V O

Output voltage

I O = 1 mA

2.835 2.85 2.864V I O = 1 to 50 mA

2.828 2.871I O = 1 to 50 mA, T J = -40 to 125°C 2.779 2.921V O

Output voltage

I O = 1 mA

2.9853

3.015V I O = 1 to 50 mA

2.978

3.023I O = 1 to 50 mA, T J = -40 to 125°C 2.925 3.075V O

Output voltage

I O = 1 mA

3.184 3.2 3.216V I O = 1 to 50 mA

3.176 3.224I O = 1 to 50 mA, T J = -40 to 125°C 3.12 3.28V O

Output voltage

I O = 1 mA

3.284 3.3 3.317V I O = 1 to 50 mA

3.275 3.325I O = 1 to 50 mA, T J = -40 to 125°C 3.217 3.383V O

Output voltage

I O = 1 mA

3.582 3.6 3.618V I O = 1 to 50 mA

3.573 3.627I O = 1 to 50 mA, T J = -40 to 125°C 3.51 3.690V O

Output voltage

I O = 1 mA

3.781 3.8 3.819V I O = 1 to 50 mA

3.772 3.829I O = 1 to 50 mA, T J = -40 to 125°C 3.705 3.895V O

Output voltage

I O = 1 mA

3.984

4.02V I O = 1 to 50 mA

3.97

4.03I O = 1 to 50 mA, T J = -40 to 125°C 3.9 4.1V O

Output voltage

I O = 1 mA

4.677 4.7 4.724V I O = 1 to 50 mA

4.665 4.735I O = 1 to 50 mA, T J = -40 to 125°C 4.582 4.818V O

Output voltage

I O = 1 mA

4.826 4.85 4.874V I O = 1 to 50 mA

4.814 4.886I O = 1 to 50 mA, T J = -40 to 125°C 4.729 4.971V O

Output voltage

I O = 1 mA

4.9755

5.025V I O = 1 to 50 mA

4.963

5.038I O = 1 to 50 mA, T J = -40 to 125°C 4.875

5.125ΔV O

Line regulation

V O(NOM) + 1 < V IN < 16 V , I O = 1 mA 0.0030.014%/V T J = -40 to 125°C

0.032

Electrical characteristics LD2980ABxx - LD2980Cxx

8/23

I Q

Quiescent current ON MODE

I O = 0

80

100μA I O = 0, T J = -40 to 125°C 150I O = 1 mA

100

150I O = 1 mA, T J = -40 to 125°C 200I O = 10 mA

175250I O = 10 mA, T J = -40 to 125°C 450I O = 50 mA

500700I O = 50 mA, T J = -40 to 125°C

1200

OFF MODE

V INH < 0.18 V

V INH < 0.18 V , T J = -40 to 125°C 1V DROP

Dropout voltage (1)

I O = 0

13mV

I O = 0, T J = -40 to 125°C 5I O = 1mA

710I O = 1mA, T J = -40 to 125°C 15I O = 10mA

4060I O = 10mA, T J = -40 to 125°C 90I O = 50mA

120150I O = 50mA, T J = -40 to 125°C

225

I SC Short circuit current R L = 0

150mA SVR Supply voltage rejection C O = 10μF , f = 1kHz

63dB V INH Inhibit input logic low LOW = Output OFF , T J = -40 to 125°C 0.8

0.18

V V INL Inhibit input logic high HIGH = Output ON, T J = -40 to 125°C 1.6

1.3V I INH Inhibit input current V INH = 0V , T J = -40 to 125°C 0-1μA V INH = 5V , T J = -40 to 125°C 515e N Output noise voltage B W = 300 Hz to 50 kHz, C O = 10μF

160μV RMS T SHDN

Thermal shutdown

170

°C 1.For V O < 2.5 V dropout voltage can be calculated according to the minimum input voltage in full temperature range.

Table 5.

Electrical characteristics for LD2980AB (continued) (T J = 25 °C, V I = V O(NOM) +1 V, C I = 1 μF(X7R), C O = 2.2 μF (X7R), I O = 1 mA, V INH = 2 V , unless otherwise specified).

Symbol

Parameter

Test conditions

Min.

Typ.Max.Unit

LD2980ABxx - LD2980Cxx Electrical characteristics

9/23

Table 6.

Electrical characteristics for LD2980C (T J = 25 °C, V I = V O(NOM) +1 V , C I = 1 μF (X7R), C O = 2.2 μF (X7R), I O = 1 mA, V INH = 2 V , unless otherwise specified)

Symbol Parameter

Test conditions

Min.Typ.

Max.Unit V OP Operating input voltage

2.516V

V O

Output voltage

I O = 1 mA

1.478 1.5 1.522V I O = 1 to 50 mA

1.470 1.530I O = 1 to 50 mA, T J = -40 to 125°C 1.445 1.555V O

Output voltage

I O = 1 mA

1.782 1.8 1.818V I O = 1 to 50 mA

1.773 1.827I O = 1 to 50 mA, T J = -40 to 125°C 1.737 1.863V O

Output voltage

I O = 1 mA

2.475 2.5 2.525V I O = 1 to 50 mA

2.463 2.538I O = 1 to 50 mA, T J = -40 to 125°C 2.412 2.587V O

Output voltage

I O = 1 mA

2.822 2.85 2.879V I O = 1 to 50 mA

2.807 2.893I O = 1 to 50 mA, T J = -40 to 125°C 2.75 2.949V O

Output voltage

I O = 1 mA

2.973

3.03V I O = 1 to 50 mA

2.955

3.045I O = 1 to 50 mA, T J = -40 to 125°C 2.895 3.105V O

Output voltage

I O = 1 mA

3.168 3.2 3.232V I O = 1 to 50 mA

3.152 3.248I O = 1 to 50 mA, T J = -40 to 125°C 3.088 3.312V O

Output voltage

I O = 1 mA

3.267 3.3 3.333V I O = 1 to 50 mA

3.251 3.35I O = 1 to 50 mA, T J = -40 to 125°C 3.184 3.415V O

Output voltage

I O = 1 mA

3.564 3.6 3.636V I O = 1 to 50 mA

3.546 3.654I O = 1 to 50 mA, T J = -40 to 125°C 3.474 3.726V O

Output voltage

I O = 1 mA

3.76 3.8 3.838V I O = 1 to 50 mA

3.743 3.857I O = 1 to 50 mA, T J = -40 to 125°C 3.667 3.933V O

Output voltage

I O = 1 mA

3.964

4.04V I O = 1 to 50 mA

3.94

4.06I O = 1 to 50 mA, T J = -40 to 125°C 3.86 4.14V O

Output voltage

I O = 1 mA

4.653 4.7 4.747V I O = 1 to 50 mA

4.630 4.771I O = 1 to 50 mA, T J = -40 to 125°C 4.535 4.864V O

Output voltage

I O = 1 mA

4.802 4.85 4.899V I O = 1 to 50 mA

4.777 4.923I O = 1 to 50 mA, T J = -40 to 125°C

4.68

5.02

Electrical characteristics LD2980ABxx - LD2980Cxx

10/23

V O

Output voltage

I O = 1 mA

4.955

5.05V I O = 1 to 50 mA

4.925

5.075I O = 1 to 50 mA, T J = -40 to 125°C 4.825

5.175ΔV O

Line regulation

V O(NOM) + 1 < V IN < 16 V , I O = 1 mA 0.0030.014%/V T J = -40 to 125°C 0.032I Q

Quiescent current ON MODE

I O = 0

80

100μA I O = 0, T J = -40 to 125°C 150I O = 1 mA

100150I O = 1 mA, T J = -40 to 125°C 200I O = 10 mA

175250I O = 10 mA, T J = -40 to 125°C 450I O = 50 mA

500700I O = 50 mA, T J = -40 to 125°C

1200

OFF MODE

V INH < 0.18 V

V INH < 0.18 V , T J = -40 to 125°C 1V DROP

Dropout voltage (1)

I O = 0

13mV

I O = 0, T J = -40 to 125°C 5I O = 1mA

710I O = 1mA, T J = -40 to 125°C 15I O = 10mA

4060I O = 10mA, T J = -40 to 125°C 90I O = 50mA

120150I O = 50mA, T J = -40 to 125°C

225

I SC Short circuit current R L = 0

150mA SVR Supply voltage rejection C O = 10μF , f = 1kHz

63dB V INH Inhibit input logic low LOW = Output OFF , T J = -40 to 125°C 0.8

0.18

V V INL Inhibit input logic high HIGH = Output ON, T J = -40 to 125°C 1.6

1.3V I INH Inhibit input current V INH = 0V , T J = -40 to 125°C 0-1μF V INH = 5V , T J = -40 to 125°C 515e N Output noise voltage B W = 300 Hz to 50 kHz, C O = 10μF

160μV RMS T SHDN

Thermal shutdown

170

°C 1.For V O < 2.5 V dropout voltage can be calculated according to the minimum input voltage in full temperature range.

Table 6.

Electrical characteristics for LD2980C (continued) (T J = 25 °C, V I = V O(NOM) +1 V , C I = 1 μF (X7R), C O = 2.2 μF (X7R), I O = 1 mA, V INH = 2 V, unless otherwise specified)

Symbol Parameter

Test conditions

Min.Typ.Max.Unit

LD2980ABxx - LD2980Cxx Typical performance characteristics 6 Typical performance characteristics

(T J = 25 °C, V I = V O(NOM) +1 V, C I = 1 μF (X7R), C O = 2.2 μF (X7R), V INH = 2 V, unless

otherwise specified)

11/23

Typical performance characteristics

LD2980ABxx - LD2980Cxx

12/23

Figure 10.Quiescent current vs output

Figure 11.Off mode quiescent current vs

LD2980ABxx - LD2980Cxx

Typical performance characteristics

13/23

Figure 16.Supply voltage rejection vs

Figure 17.Noise voltage vs frequency

Figure 20.Load transient response

Figure 21.Line transient response

V O = 4.7V, I O = 1 to 100mA, C O = 4.7μF (X7R)

V I = [V O(NOM) +1V], V O = 4.7V, I O = 100mA, C O = 4.7μF

(X7R)

Application notes

LD2980ABxx - LD2980Cxx

14/23

7 Application notes

7.1 External capacitors

Like any low-dropout regulator, the LD2980 requires external capacitors for regulator

stability. This capacitor must be selected to meet the requirements of minimum capacitance and equivalent series resistance. We suggest to solder input and output capacitors as close as possible to the relative pins.

7.2 Input capacitor

An input capacitor whose value is 1 μF is required with the LD2980 (amount of capacitance

can be increased without limit). This capacitor must be located a distance of not more than 0.5" from the input pin of the device and returned to a clean analog ground. Any good quality ceramic, tantalum or film capacitors can be used for this capacitor.

7.3 Output capacitor

The LD2980 is designed specifically to work with ceramic output capacitors. It may also be

possible to use Tantalum capacitors, but these are not as attractive for reasons of size and cost. By the way, the output capacitor must meet both the requirement for minimum amount of capacitance and ESR (equivalent series resistance) value. The Figure 4 and Figure 5 show the allowable ESR range as a function of the output capacitance. These curves

represent the stability region over the full temperature and I O range. Due to the different loop gain, the stability improves for higher output versions and so the suggested minimum output capacitor value, if low ESR ceramic type is used, is 1 μF for output voltages equal or major than 3.8 V , 2.2 μF for output voltages from 2.85 to 3.3 V, and 3.3 μF for the other versions. However, if an output capacitor lower than the suggested one is used, it’s possible to make stable the regulator adding a resistor in series to the capacitor (see Figure 1 and Figure 2 to choose the right value according to the used version and keeping in account that the ESR of ceramic capacitors has been measured @ 100 kHz).

7.4 Important

The output capacitor must maintain its ESR in the stable region over the full operating temperature to assure stability. Also, capacitor tolerance and variation with temperature must be considered to assure the minimum amount of capacitance is provided at all times. This capacitor should be located not more than 0.5" from the output pin of the device and returned to a clean analog ground.

7.5 Inhibit input operation

The inhibit pin can be used to turn OFF the regulator when pulled low, so drastically

reducing the current consumption down to less than 1 μA. When the inhibit feature is not used, this pin must be tied to V I to keep the regulator output ON at all times. To assure

proper operation, the signal source used to drive the inhibit pin must be able to swing above and below the specified thresholds listed in the electrical characteristics section under V IH V IL . Any slew rate can be used to drive the inhibit.

LD2980ABxx - LD2980Cxx

Application notes

15/23

7.6 Reverse current

The power transistor used in the LD2980 has not an inherent diode connected between the

regulator input and output. If the output is forced above the input, no current will flow from the output to the input across the series pass transistor. When a V REV voltage is applied on the output, the reverse current measured, according to the test circuit in Figure 22, flows to the GND across the two feedback resistors. This current typical value is 160 μA. R 1 and R 2 resistors are implanted type; typical values are, respectively, 42.6 k Ω and 51.150 k Ω.

Package mechanical data LD2980ABxx - LD2980Cxx 8 Package mechanical data

In order to meet environmental requirements, ST offers these devices in ECOPACK?

packages. These packages have a lead-free second level interconnect. The category of

second Level Interconnect is marked on the package and on the inner box label, in

compliance with JEDEC Standard JESD97. The maximum ratings related to soldering

conditions are also marked on the inner box label. ECOPACK is an ST trademark.

ECOPACK specifications are available at: https://www.wendangku.net/doc/e614164417.html,.

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LD2980ABxx - LD2980Cxx Package mechanical data

Package mechanical data LD2980ABxx - LD2980Cxx

LD2980ABxx - LD2980Cxx Package mechanical data

Package mechanical data LD2980ABxx - LD2980Cxx

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