STMICROELECTRONICS LD3986J285R-E

LD3986
SERIES
DUAL ULTRA LOW DROP-LOW NOISE BICMOS VOLTAGE
REG. FOR USE WITH VERY LOW ESR OUT. CAPACITORS
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INPUT VOLTAGE FROM 2.5V TO 6V
STABLE WITH LOW ESR CERAMIC
CAPACITORS
ULTRA LOW DROPOUT VOLTAGE (60mV
TYP. AT 150mA LOAD, 0.4mV TYP. AT 1mA
LOAD)
VERY LOW QUIESCENT CURRENT (155µA
TYP. AT NO LOAD, 290µA TYP. AT 150mA
LOAD; MAX 2µA IN OFF MODE)
GUARANTEED OUTPUT CURRENT UP TO
150mA FOR BOTH OUTPUTS
DUAL OUTPUT VOLTAGES
FAST TURN-ON TIME: TYP. 120µs (CO=1µF,
CBYP=10nF AND IO=1mA)
LOGIC-CONTROLLED ELECTRONIC
SHUTDOWN
INTERNAL CURRENT AND THERMAL LIMIT
OUTPUT LOW NOISE VOLTAGE 30µVRMS
OVER 10Hz to 100KHz
S.V.R. OF 50dB AT 1KHz, 40dB AT 10KHz
TEMPERATURE RANGE: -40°C TO 125°C
DESCRIPTION
The LD3986 provides up to 150mA at each output,
from 2.5V to 6V input voltage. The ultra low
drop-voltage, low quiescent current and low noise
Flip-Chip
make it suitable for low power applications and in
battery powered systems. Regulator ground
current increases only slightly in dropout, further
prolonging the battery life. Power supply rejection
is 50 dB at 1KHz and 40 dB at 10KHz. High power
supply rejection is maintained down to low input
voltage levels common to battery operated
circuits. Shutdown Logic Control function is
available for each output, 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 LD3986 is
designed to work with low ESR ceramic
capacitors. Typical applications are in mobile
phone and similar battery powered wireless
systems.
Figure 1: Schematic Diagram
September 2005
Rev. 3
1/12
LD3986 SERIES
Table 1: Order Codes
Flip-Chip
Flip-Chip (Lead Free)
1 OUTPUT VOLTAGES
2 OUTPUT VOLTAGES
LD3986J122R-E
LD3986J12248R-E
LD3986J1828R-E
LD3986J2528R-E (*)
LD3986J28R-E
LD3986J285R-E
LD3986J29R-E (*)
LD3986J30R-E (*)
LD3986J2830R-E (*)
LD3986J3133R-E (*)
LD3986J33R-E
1.22 V
1.22 V
1.8 V
2.5 V
2.8 V
2.85 V
2.9 V
3.0 V
2.8 V
3.1 V
3.3 V
1.22 V
4.8 V
2.8 V
2.8 V
2.8 V
2.85 V
2.9 V
3.0 V
3.0 V
3.3 V
3.3 V
LD3986J12248R
LD3986J285R
(*) Available on Request.
Table 2: Absolute Maximum Ratings
Symbol
VI
Parameter
DC Input Voltage
VO1,2
DC Output Voltage
VEN1,2
ENABLE Input Voltage
Value
Unit
-0.3 to 6
V
-0.3 to VI+0.3
V
V
IO
Output Current
-0.3 to VI+0.3
Internally limited
PD
Power Dissipation
Internally limited
TSTG
Storage Temperature Range
-65 to 150
°C
TOP
Operating Junction Temperature Range
-40 to 125
°C
Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these condition is
not implied.
Table 3: Thermal Data
Symbol
Rthj-amb
2/12
Parameter
Thermal Resistance Junction-Ambient
Flip-Chip
Unit
120
°C/W
LD3986 SERIES
Figure 2: Pin Connection (top through view)
Table 4: Pin Description
Symbol
Pin N°
Name and Function
VO2
A1
Output Voltage 2 of the dual LDO
EN2
B1
BYPASS
GND
GND
EN1
C1
C2
C3
B3
VO1
A3
Enables voltage for output voltage 2: ON MODE when VEN ≥ 1.4V, OFF MODE when VEN ≤
0.4V (Do not leave floating, not internally pulled down/up)
Bypass Pin: Connect an external capacitor (usually 10nF) to minimize noise voltage
Common Ground
Common Ground
Enables voltage for output voltage 1: ON MODE when VEN ≥ 1.4V, OFF MODE when VEN ≤
0.4V (Do not leave floating, not internally pulled down/up)
Output Voltage 1 of the dual LDO
VI
A2
Input Voltage for both LDO
Figure 3: Typical Application Circuit
3/12
LD3986 SERIES
Table 5: Electrical Characteristics For LD3986 (Tj = 25°C, VI = VO(NOM) +0.5V, CI = C O =1µF,
CBYP = 10nF, IO = 1mA, VEN = 1.4V, unless otherwise specified)
Symbol
VI
∆VO
Parameter
Test Conditions
Min.
Operating Input Voltage
Output Voltage Tolerance
IO = 1mA
TJ= -40 to 125°C
∆VO
Line Regulation (Note 1)
Max.
Unit
2.5
6
V
-2.5
2.5
% of VO
-3
3
VI = VO(NOM) + 0.5 V to 6V
Typ.
0.006
TJ= -40 to 125°C
∆VO
Load Regulation
IO = 1 mA to 150mA
0.003
TJ= -40 to 125°C
∆VO
IQ
IO = 0
IO = 0
ONE REGULATOR
ON MODE: VEN = 1.4V
µA
200
TJ= -40 to 125°C
370
TJ= -40 to 125°C
IO = 0
IO = 0 to 150mA
Dropout Voltage (Note 2)
150
290
TJ= -40 to 125°C
130
165
TJ= -40 to 125°C
220
IO = 1mA
IO = 1mA
0.4
TJ= -40 to 125°C
mV
2
IO = 150mA
IO = 150mA
2
4
95
IO = 0 to 150mA
VDROP
%/mA
mVPP
0.001
IO = 0
0.006
1.5
TJ= -40 to 125°C
IO = 0 to 150mA
IO = 0 to 150mA
BOTH OFF MODE:
VEN = 0.4V
%/V
0.01
Output AC Line Regulation VI = VO(NOM) + 1 V, IO = 150mA,
(See fig. 5)
tR= tF = 30µs
Quiescent Current
BOTH ON MODE:
VEN = 1.4V
0.092
0.128
50
TJ= -40 to 125°C
100
Supply Voltage Rejection
(See fig. 4)
VI = VO(NOM)+0.25V ±
f = 1KHz
VRIPPLE = 0.1V, IO= 50mA f = 10KHz
VO(NOM) < 2.5V,
VI = 2.55V
ISC
Short Circuit Current
RL = 0
IO(PK)
Peak Output Current
VO ≥ VO(NOM) - 5%
Enable Input Logic Low
(Note 3)
Enable Input Logic High
(Note 3)
Enable Input Current
VI = 2.5V to 6V
±10
nA
Crosstalk Rejection
∆ILOAD1 = 150 mA at 1KHz rate
ILOAD2 = 1 mA, VO2 under test
40
µV
∆ILOAD2 = 150 mA at 1KHz rate
ILOAD1 = 1 mA, VO1 under test
40
SVR
VEN
IEN
XTALK
300
50
40
dB
600
mA
550
mA
TJ= -40 to 125°C
0.4
V
1.4
VEN = 0.4V
VI = 6V
µVRMS
Output Noise Voltage
tON
Turn On Time (Note 4)
CBYP = 10 nF
50
µs
Thermal Shutdown (Note
4)
(Note 3)
160
°C
TSHDN
4/12
BW = 10 Hz to 100 KHz
CO = 1 µF
eN
30
LD3986 SERIES
Symbol
CO
Parameter
Output Capacitor
Test Conditions
Capacitance
ESR
Min.
1
0.005
Typ.
Max.
Unit
22
5
µF
Ω
Note 1: For VO< 2V, VI=2.5V
Note 2: Dropout voltage is the input-to-output voltage difference at which the output voltage is 100mV below its nominal value. This specification does not apply for input voltages below 2.5V.
Note 3: Enable pin must be driven with a TR = TF < 10ms
Note 4: Turn-on time is time measured between the enable input just exceeding VINH High Value and the output voltage just reaching 95%
of its nominal value
Note 5: Typical thermal protection hysteresis is 20°C
Figure 4: SVR Input Voltage Test Signal
Figure 5: AC Line Regulation Input Voltage Test Signal
5/12
LD3986 SERIES
TYPICAL PERFORMANCE CHARACTERISTICS (Tj = 25°C, VI = VO(NOM) +0.5V, CI = CO = 1µF,
CBYP = 10nF, IO = 1mA, VEN = 1.4V, unless otherwise specified)
Figure 6: VO1,2 vs Temperature
Figure 9: Load Regulation vs Temperature
Figure 7: VO1,2 vs Temperature
Figure 10: Quiescent Current vs Temperature
Figure 8: Line Regulation vs Temperature
Figure 11: Quiescent Current vs Temperature
6/12
LD3986 SERIES
Figure 12: Supply Voltage Rejection vs
Frequency
Figure 15: Load Transient Response
IO1 = 1 mA, IO2 = 0mA, TR = TF = 10µs
Figure 13: Supply Voltage Rejection vs
Temperature
Figure 16: TURN-ON
VI = 3.2V, VEN1,2 = 0 to 1.4V, IO1,2 = 1mA, TR = TF = 1µs
Figure 14: Line Transient Response
Figure 17: TURN-OFF
VI = 3.2V to 3.8V, IO1 = IO2 = 150mA, TR = TF = 10µs
VI = 3.2V, VEN1,2 = 1.4 to 0V, IO1,2 = 1mA, TR = TF = 1µs
7/12
LD3986 SERIES
APPLICATION INFORMATION
CURRENT LIMIT
The device includes short-circuit protection. It
includes a current limiter that controls the pass
transistor’s gate voltage to limit the output current
to about 600mA.
THERMAL OVERLOAD PROTECTION
The Thermal over load protection limits total
power dissipation in the device. When the junction
temperature (TJ) exceeds +160°C, the thermal
sensor sends a signal to the shutdown logic,
turning off the pass transistors and allowing the
device to cool. The pass transistors turns on again
after the device’s junction temperature typically
cools by 20°C, resulting in a pulsed output during
continuous thermal overload conditions.
POWER DISSIPATION
Maximum power dissipation of the device
depends on the thermal resistance of the case
and circuit board, the temperature difference
between the die junction and ambient air, and the
rate of air flow. The power dissipated by the
device is:
PD = IO (VI -VO)
The maximum power dissipation is:
PMAX = (TJMAX - TA) / RTH
Where:
TJMAX = +125°C
TA is the ambient temperature
RTH thermal resistance.
The device’s pins perform the dual function of
providing an electrical connection as well as
channeling heat away from the die. Use wide
circuit-board traces and large, solid copper
polygons to improve power dissipation. Using
multiple vias to buried ground planes further
enhances thermal conductivity.
INPUT CAPACITOR
An input capacitance of ≈ 1µF is required between
the LD3986 input pin and ground (the amount of
the capacitance may be increased without limit).
This capacitor must be located a distance of not
more than 1cm from the input pin and returned to
a clean analog ground. Any good quality ceramic,
tantalum, or film capacitor may be used at the
input.
8/12
Important: Tantalum capacitors can suffer
catastrophic failures due to surge current when
connected to a low impedance source of power
(like a battery or a very large capacitor). If a
tantalum capacitor is used at the input, it must be
guaranteed by the manufacturer to have a surge
current rating sufficient for the application.
There are no requirements for the ESR on the
input capacitor, but tolerance and temperature
coefficient must be considered when selecting the
capacitor to ensure
the capacitance will be ≈ 1µF over the entire
operating temperature range.
OUTPUT CAPACITOR
The LD3986 is designed specifically to work with
very small ceramic output capacitors, any ceramic
capacitor (temperature characteristics X7R, X5R,
Z5U or Y5V) in 1 to 22 µF range with 5m. to 500m.
ESR range is suitable in the LD3986 application
circuit. it may also be possible to use tantalum or
film capacitors at the output, but these are not as
attractive for reasons of size and cost.
The output capacitor must meet the requirement
for minimum amount of capacitance and also have
an ESR (Equivalent Series Resistance) value
which is within a stable range.
NOISE BYPASS CAPACITOR
Connecting a 0.01µF capacitor between the CBYP
pin and ground significantly reduces noise on both
regulator outputs.
This cap is connected directly to a high impedance
node in the band gap reference circuit. Any
significant loading on this node will cause a
change on the regulated output voltage.
For this reason, DC leakage current through this
pin must be kept as low as possible for best output
voltage accuracy. The use of this 0.01µF bypass
capacitor is strongly recommended to prevent
overshoot on the output during start up.
The types of capacitors best suited for the noise
bypass capacitor are ceramic and film.
High-quality ceramic capacitors with either NPO
or COG dielectric typically have very low leakage.
Polypropylene and polycarbonate film capacitors
are available in small surface-mount packages
and typically have extremely low leakage current.
Unlike many other LDO’s, addition of a noise
reduction capacitor does not effect the transient
response of the device.
TURN-ON/OFF INPUT OPERATION
Each LD3986 output is turned off by pulling the
relevant EN pin low, and turned on by pulling it
high. To assure proper operation, the signal
LD3986 SERIES
source used to drive the EN input must be able to
swing above and below the specified turn-on/off
voltage thresholds listed in the Electrical
Characteristics section under Enable Input Logic
Low and Enable Input Logic High.
Proper operation of the Enable function is
guaranteed by driving EN pins with TR and TF = 10
ms.
FAST ON-TIME
The LD3986 outputs are turned on after VREF
voltage reaches its final value (1.23V nominal). To
speed up this process, the noise reduction
capacitor at the bypass pin is charged with an
internal 70µA current source. The current source
is turned off when the bandgap voltage reaches
approximately 95% of its final value. The turn on
time is determined by the time constant of the
bypass capacitor. The smaller the capacitor value,
the shorter the turn on time, but less noise gets
reduced. As a result, turn on time and noise
reduction need to be taken into design
consideration when choosing the value of the
bypass capacitor.
9/12
LD3986 SERIES
Flip-Chip8 MECHANICAL DATA
mm.
mils
DIM.
MIN.
TYP
MAX.
MIN.
TYP.
MAX.
A
0.585
0.65
0.715
23.0
25.6
28.1
A1
0.21
0.25
0.29
8.3
9.8
11.4
A2
0.40
15.7
b
0.265
0.315
0.365
10.4
12.4
14.4
D
1.52
1.57
1.62
59.8
61.8
63.8
D1
E
1
1.52
E1
e
1.57
39.4
1.62
59.8
1
0.45
0.5
61.8
63.8
39.4
0.55
17.7
19.7
f
0.285
11.2
ccc
0.080
3.1
20.7
7224720E
10/12
LD3986 SERIES
Table 6: Revision History
Date
Revision
07-Dec-2004
06-Jun-2005
22-Sep-2005
1
2
3
Description of Changes
First Release.
Add New Part Number - Table 1.
Order Codes has been updated.
11/12
LD3986 SERIES
Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences
of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted
by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject
to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not
authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics.
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All other names are the property of their respective owners
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