SEMTECH SC2738

SC2738
Ultra Low Output Voltage
Dual Linear FET Controller
POWER MANAGEMENT
Description
Features
‹ ±3.5% reference voltage
‹ Two independant and fully adjustable outputs
‹ Wide supply voltage range permits operation from
The SC2738 is an ultra low output voltage dual power
supply controller designed to simplify power management
for desktop PCs and graphics cards. It is part of Semtech’s
Smart LDOTM family of products. The SC2738 has two
user adjustable outputs that can be set anywhere between 0.5V and 3.3V (VIN = 12V, anywhere between 0.5V
and 1.8V for VIN = 5V) using two external resistors per
output.
‹
‹
‹
SC2738 features for each output include tight output
voltage regulation (±3.5% over -40°C to +85°C), enable
controls, open drain power good signals, under-voltage
protection and soft start. The enable pins allow the part
to enter a very low power standby mode. Pulling them
high enables the outputs. The power good pins are open
drain and assert low when the voltage at their
respective adjust pins is below 88% (typ.) of nominal. If
the voltage at the adjust pin is below 50% (typ.) of
nominal, the under-voltage protection circuitry will shut
down that output. The SC2738 is available in an
MSOP-10 surface mount package.
‹
‹
‹
‹
5V or 12V rails
Very low quiescent current (500µA typical with both
outputs enabled and 5V input)
Indivdual Enable control for each output
Individual Power Good monitoring and signalling for
each output
Gate drives from input supply enable use of
N-channel MOSFETs
User selectable dropout voltage
Individual under-voltage protection for each output
MSOP-10 surface mount package
Applications
‹ Desktop PCs
‹ Graphics cards
‹ Simple dual power supplies
Typical Application Circuit
5V or 12V IN
VIN1
VIN2
C1
C2
0.1uF (1)
0.1uF (1)
7
8
6
5
1
VOUT1
3
C3
C4
2
100uF, 25mOhm POSCAP
R1
R5 2k (2)
11.0k
1
2
3
OUT1 Enable
4
OUT1 Power Good
5
R1 

VOUT1 = 0.5 • 1 +

 R2 
Revision: November 16, 2004
VOUT2
Q1
4
U1
SC2738
DRV1
IN
ADJ1
DRV2
EN1
ADJ2
PGD1
GND
EN2
PGD2
9
100uF, 25mOhm POSCAP
R3
10
R6 2k (2)
20.0k
8
7
OUT2 Enable
6
OUT2 Power Good
R2
C5
C6
C7
R4
10.0k
10nF (2)
0.1uF
10nF (2)
10.0k
Notes:
(1) Additional capacitance may be required if far from supply
(2) Optional soft-start components
1
 R3 
VOUT 2 = 0.5 • 1 +

 R4 
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SC2738
POWER MANAGEMENT
Absolute Maximum Ratings
PRELIMINARY
Exceeding the specifications below may result in permanent damage to the device, or device malfunction. Operation outside of the parameters
specified in the Electrical Characteristics section is not implied. Exposure to Absolute Maximum rated conditions for extended periods of time may
affect device reliability.
Parameter
Input Supply Voltage
Drive Pins
Symbol
Maximum
Units
VIN
-0.3 to +13.2
V
VDRV
-0.3 to +8.0
V
VADJ, VPGD
Adjust and Power Good Pins
-0.3 to +5.5
V
(1)
Enable Pins
V EN
-0.3 to VIN
V
Thermal Impedance Junction to Ambient
θJ A
113
°C/W
Thermal Impedance Junction to Case
θJ C
42
°C/W
Operating Ambient Temperature Range
TA
-40 to +85
°C
Operating Junction Temperature Range
TJ
-40 to +150
°C
Storage Temperature Range
TSTG
-65 to +150
°C
Lead Temperature (Soldering) 10 Sec.
TLEAD
300
°C
ESD Rating (Human Body Model)
ESD
2
kV
Note:
(1) Or VIN, if VIN ≤ 5V.
Electrical Characteristics
Unless specified: TA = 25°C, VIN = VEN = 5V ± 5%, VPWR(1) = 1.5V ± 5%, 0A ≤ IOUT ≤ 3A.
Values in bold apply over full operating ambient temperature range.
Parameter
Symbol
Test Conditions
Min
Typ
Max
Units
13.2
V
IN
Supply Voltage
VIN
Quiescent Current
IQ
Standby Current
IQ(OFF)
4.5
VIN = 5V
500
700
µA
VIN = 12V
600
900
µA
Both EN low
0.1
1.0
µA
Both EN low, VIN = 12V
15.0
Undervoltage Lockout
Start Threshold
VUVLO
VIN rising
3.75
V
Hysteresis
VHYST
VIN falling
0.50
V
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SC2738
POWER MANAGEMENT
Electrical Characteristics (Cont.)
Unless specified: TA = 25°C, VIN = VEN = 5V ± 5%, VPWR(1) = 1.5V ± 5%, 0A ≤ IOUT ≤ 3A.
Values in bold apply over full operating ambient temperature range.
Parameter
Symbol
Test Conditions
Min
VIH
Output on
1.3
VIL
Output off
IEN
V E N = 0V
Typ
Max
Units
EN
Enable Input Threshold
Enable Input Bias Current
0.7
0
V
µA
VIN = VEN = 5V or 12V
-1
+1
VADJ = 0.5V
-100
0
+100
nA
-3.5%
0.500
+3.5%
V
ADJ
Adjust Input Bias Current
IADJ
Reference Voltage
V AD J
DRV
Output Current
IDRV
Sourcing, startup
(until VTH(PGD) is reached)
10
µA
Sourcing, after startup
0.7
2.0
mA
Sinking
350
700
µA
Full On, IDRV = 0mA, VIN = 12V
6.6
6.9
V
Full On, IDRV = 0mA, VIN = 5V
4.70
4.85
VTH(UV)
Measured at ADJ pin
40
50
60
%VADJ
VTH(PGD)
Measured at ADJ pin
-15
-12
-9
%VADJ
Output Logic Low Voltage
VPGD
VADJ = 0.4V, IPGD = -1mA
0.4
V
Power Good Leakage
Current
IPGD
VADJ = 0.5V, 0V ≤ VPGD ≤ VIN
+1
µA
tr
CDRV-GND = not placed
150
CDRV-GND = 10nF
850
Output Voltage
VDRV
Under Voltage Protection
Trip Threshold
(1)
PGD
Power Good Threshold
(2)
-1
0
Soft Start
Output Rise Time
10% VOUT to 90% VOUT
VOUT = 1.05V
µs
Error Amplifier
Open Loop Gain
AVOL
52
dB
Gain Bandwidth
GBW
1
MHz
Notes:
(1) If VTH(UV) is exceeded for longer than 50µs (nom.) the protection circuitry will shut down that output.
(2) During startup only, VTH(PGD) is -6% (typ.), then switches to -12% (typ.).
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SC2738
POWER MANAGEMENT
Pin Configuration
PRELIMINARY
Ordering Information
Top View
Part Number(1)
Output Voltage
P ackag e
SC2738IMSTRT(2)
Both adj. from
0.5V to 3.3V
MSOP-10
Notes:
(1) Only available in tape and reel packaging. A reel
contains 2500 devices.
(2) Lead free product. This product is fully WEEE and
RoHS compliant.
(MSOP-10)
Pin Descriptions
Pin
Pin Name Pin Function
1
DRV1
Output of regulator #1, output impedance ~ 1k Ω. Drives the gate of an N-channel MOSFET to maintain
VOUT1 set by R1 and R2.
2
A D J1
Regulator #1 sense input. Used for sensing the output voltage for power good and under-voltage, and
to set the output voltage as follows (refer to application circuit on page 1):
R1 

VOUT1 = 0.5 • 1 +

 R2 
VOUT(MAX) = 3.3V for VIN = 12V, 1.8V for VIN = 5V.
3
EN1
Active high enable control. Connect to IN if not being used. Do not allow to float.
4
PGD1
Power good signal output for VOUT1. Open drain output pulls low when VOUT1 is below (VOUT1(NOM) -12%).
5
GND
Ground.
6
PGD2
Power good signal output for VOUT2. Open drain output pulls low when VOUT2 is below (VOUT2(NOM) -12%).
7
EN2
Active high enable control. Connect to IN if not being used. Do not allow to float.
8
A D J2
Regulator #2 sense input. Used for sensing the output voltage for power good and under-voltage, and
to set the output voltage as follows (refer to application circuit on page 1):
 R3 
VOUT 2 = 0.5 • 1 +

 R4 
V
= 3.3V for V = 12V, 1.8V for V = 5V.
OUT(MAX)
9
DRV2
10
IN
 2004 Semtech Corp.
IN
IN
Output of regulator #2, output impedance ~ 1k Ω. Drives the gate of an N-channel MOSFET to maintain
VOUT2 set by R3 and R4.
+5V or +12V supply.
4
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SC2738
POWER MANAGEMENT
Block Diagram
(0.94 VBG
at start-up)
(0.94 VBG
at start-up)
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SC2738
POWER MANAGEMENT
Applications Infomation
PRELIMINARY
and 3.75mA at 12V in during normal operation. The high
side drive voltage is generated from VIN by a 7V (nominal)
low dropout regulator, thus at 12V in, 6.9V is available
and at 5V in, 4.85V is available (since the LDO will be in
dropout).
Theory Of Operation
The SC2738 dual linear FET controller provides a simple
way to drive two N-channel MOSFETs to produce tightly
regulated output voltages from one or two available,
higher, supply voltages. It takes its power from either a
5V or 12V supply, drawing typically 500µA while
operating.
At start-up, the source current available from the drive
pins is limited to 10µA (typical) until the power good
threshold is reached, at approximately 6% below
nominal output voltage. At this point the full drive
capability is enabled. With this constant current source
at start-up, it is a simple matter to use a small capacitor
on the drive pin to slow this rate of rise. The rate of rise
of the drive pin voltage will be:
It contains an internal bandgap reference which is
compared to the output voltages via resistor dividers.
These resistor dividers are external and user selectable .
Depending upon the input voltage used for the device,
the drive pin (DRV1, DRV2) can pull up to a guaranteed
minimum of 6.6V (from 12V supply) or 4.7V (from 5V
supply). Thus the device can be used to regulate a large
range of output voltages by careful selection of the
external MOSFETs (see component selection, below).
dVDRV IDRV
=
V/s
dt
CSS
A 10nF soft start capacitor will give a 1ms output rise
time for VIN = 12V and VOUT = 1.05V, for example. The
output rise time will of course depend upon the gate
threshold of the MOSFET being used. Please refer to
the Output Rise Time chart on Page 12 showing typical
output rise times. For very low ESR output capacitors
(<5mΩ) and very high soft start capacitance (>100nF),
it may be necessary to add a resistor in series with the
soft start capacitor to ensure stability. Generally,
however, this resistor is not required, as this is a very
unlikely situation.
The SC2738 includes an active high enable control (EN1,
EN2) for each output. If this pin is pulled low, the related
drive pin is pulled low, turning off the N-channel MOSFET.
If the pin is pulled up to 1.8V ≤ VEN ≤ VIN, the drive pin will
be enabled. This pin should not be allowed to float.
Each output has a power good output (PGD1, PGD2)
which are open drain outputs that pull low if the related
output is below the power good threshold (-12% of the
programmed output voltage typical, -6% typical at startup). The power good circuitry is active if the device is
enabled, regardless of the state of the over current latch.
The power good circuitry is not active if that
particular output is disabled.
The soft start capacitance does not adversely affect
transient response since the drive current capability is
200 times higher once the device has started.
OCP and Power Supply Sequencing
Also included for each output is an overcurrent
protection circuit that monitors the output voltage. If the
output voltage drops below 50% (typ.) of nominal, as
would occur during an overcurrent or short condition, the
device will pull the drive pin low and latch off. The device
will need to have the power supply or enable pin toggled
to reset the latch condition. Each output latches
independently (i.e. if one output latches off, the other
output will function normally).
The SC2738 has output under-voltage protection that
looks at a particular output to see if it is a) less than
50% (typical) of it’s nominal value and b) VDRV for that
output is within 350mV (typical) of maximum. If both of
these criteria are met, there is a 50µs (typical) delay and
then the output is shut down. This provides inherent
immunity to UV shutdown at start-up (which may occur
while the output capacitors are being charged) since VDRV
has a very slow rate of rise with IDRV limited to 10µA.
Drive Outputs and Soft Start
At start-up, it is necessary to ensure that the power
supplies and enables are sequenced correctly to avoid
erroneous latch-off. For UV latch-off not to occur at startup due to sequencing issues, the key is that the voltage
The drive outputs for each output are source and sink
capable. The sink current is typically 0.8mA at 5V in (1mA
at 12V in). The source current is typically 2mA at 5V in
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SC2738
POWER MANAGEMENT
Applications Infomation (Cont.)
simplicity. Worst case under-voltage threshold is 60%
(over temperature) of 1.5V, or 0.9V. The typical enable
threshold is ~1V. See Figure 1 below.
supplied to the MOSFET drain should be greater than
the output under-voltage threshold when that
output is enabled. This assumes that the drop through
the pass MOSFET is negligible. If not, then this drop needs
to be taken into account also since:
VOUT = VDRAIN - (IOUT x RDS(ON)).
Component Selection
Output Capacitors: low ESR capacitors such as Sanyo
POSCAPs or Panasonic SP-caps are recommended for
bulk capacitance, with ceramic bypass capacitors for
decoupling high frequency transients.
Input Capacitors: placement of low ESR capacitors such
as Sanyo POSCAPs or Panasonic SP-caps at the input to
the MOSFET (VDRAIN) will help to hold up the power supply
during fast load changes, thus improving overall transient
response. If VDRAIN is located at the bulk capacitors for
the upstream voltage regulator, additional capacitance
may not be required. In this case a 0.1µF ceramic
capacitor will suffice. The input supply to the SC2738
should be bypassed with a 0.1µF ceramic capacitor.
If the supply to the SC2738 IN pin comes up before the
supply to the MOSFET drain, then that output should be
enabled as the supply to the MOSFET drain is applied
- the Power Good signal for this rail would be ideal. If the
power supply to the MOSFET drain comes up before the
power supply to the SC2738 IN pin, then the output can
either be enabled with the supply to the IN pin or afterwards. Please see the example below.
Example: SC2738 powered from 5V, output 1 powered
from 1.8V set for 1.5V out, output 2 not shown for
SC2738 Supply Comes Up Before MOSFET Drain Supply
MOSFET Drain Supply Comes Up Before SC2738 Supply
Figure 1: Power Supply Sequencing
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SC2738
POWER MANAGEMENT
Applications Infomation (Cont.)
PRELIMINARY
MOSFETs: very low or low threshold N-channel MOSFETs
are required. Selecting FETs rated for VGS of 2.7V or 4.5V
will depend upon the available drive voltage (6.9V from
12V in or 4.85V from 5V in), the output voltage and
output current. For the device to work under all
operating conditions, a maximum RDS(ON) must be met to
ensure that the output will never go into dropout:
RDS( ON)(MAX ) =
VIN(MIN ) − VOUT (MAX )
IOUT (MAX )
Ω
VOUT (V)
R1 or R3 (kΩ )
R2 or R4 (kΩ )
1.05
11.0
10.0
1.2
14.0
10.0
1.5
20.0
10.0
2.5
45.3
11.3
3.3
63.4
11.3
Table 1: Recommended Resistor Values For SC2738
Note that RDS(ON) must be met at all temperatures and at
the minimum VGS condition.
Design Example
Setting The Output Voltage: the adjust pins connect
directly to the inverting input of the error amplifiers, and
the output voltage is set using external resistors (please
refer to the Typical Application Circuit on page 1).
Goal: 1.5V±5% static and ±7% transient @ up to 4A
from 2.5V±5% and 5V±5%
Total window for DC error and ripple is ±75mV.
Total window for transient is ±105mV.
Using output 1 as an example, the output voltage can
be calculated as follows:
Since this device is linear, and assuming that it has been
designed to not ever enter dropout, we do not have ripple
on the output.
R1 

VOUT = 0.5 • 1 +

 R2 
The input bias current for the adjust pin is so low that it
can be safely ignored. To avoid picking up noise, it is
recommended that the total resistance of the feedback
chain be less than 100kΩ.
The DC error for this output is the sum of:
VREF accuracy = ±3.5% = ±52.5mV
Feedback chain tolerance = ±1% = ±15mV
Please see Table 1 on this page for recommended
resistor values for some standard output voltages. All
resistors are 1%, 1/10W.
Load regulation = ±0.25% = ±3.8mV
Set resistors per Table 1 should be 20.0kΩ (top) and
10.0kΩ (bottom).
The maximum output voltage that can be obtained from
each output is determined by the input supply voltage
and the R DS(ON) and gate threshold voltage of the
external MOSFET. Assuming that the MOSFET gate
threshold voltage is sufficiently low for the output
voltage chosen and the worst-case drive voltage, VOUT(MAX)
is given by:
Total DC error = ±4.75% = 71.3mV
This leaves ±2.25% = 33.7mV for the load transient ESR
spike, therefore:
R ESR(MAX ) =
VOUT (MAX ) = VDRAIN(MIN ) − IOUT (MAX ) • RDS( ON)(MAX )
33.7mV
= 8.4m Ω
4A
Bulk capacitance required is given by:
dI • t
µF
dV
Where dI is the maximum load current step, t is the
maximum regulator response time and dV is the
allowable voltage droop. Therefore with dI = 4A,
t = 1µs, and dV = 33.7mV:
CBULK (MIN ) =
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SC2738
POWER MANAGEMENT
Applications Infomation (Cont.)
CBULK (MIN) =
4 • 1• 10 −6
= 119µF
33.7 • 10 − 3
Layout Guidelines
The advantages of using the SC2738 to drive external
MOSFETs are a) that the bandgap reference and control
circuitry are in a die that does not contain high power
dissipating devices and b) that the device itself does not
need to be located right next to the power devices. Thus
very accurate output voltages can be obtained since
changes due to heating effects will be minimal.
So if we use 1% VOUT set resistors we would select 2 x
>100µF, 18mΩ POSCAPs for output capacitance (which
assumes that local ceramic bypass capacitors will
absorb the balance of the (9 - 8.4)mΩ ESR
requirement - otherwise 15mΩ capacitors should be
used).
If we use 0.1% set resistors, then the total DC error
becomes ±3.85% = ±57.8mV, leaving ±3.15% = 47.2mV
for the ESR spike. In this case:
R ESR(MAX ) =
CBULK (MIN) =
The 0.1µF bypass capacitor should be located close to
the supply (IN) and GND pins, and connected directly to
the ground plane.
47.2mV
= 11.8mΩ and
4A
The feedback resistors should be located at the device,
with the sense line from the output routed from the load
(or top end of the droop resistor if passive droop is being
used) directly to the feedback chain. If passive droop is
being used, the droop resistor should be located right at
the load to avoid adding additional unplanned droop.
−6
4 • 1• 10
= 85µF
47.2 • 10 − 3
So for 0.1% resistors we could use 1 x 100µF, 12mΩ
POSCAPs for output capacitance.
The input capacitance needs to be large enough to stop
the input supply from collapsing below -5% (i.e. the
design minimum) during output load steps. If the input to
the pass MOSFET is not local to the supply bulk
capacitance then additional bulk capacitance may be
required.
Sense and drive lines should be routed away from noisy
traces or components.
For very low input to output voltage differentials, the
input to output / load path should be as wide and short
as possible. Where greater headroom is available, wide
traces may suffice.
MOSFET selection: since the input voltage to the SC2738
is 5V±5%, the minimum available gate drive is:
Power dissipation within the device is practically
negligible, thus requiring no special consideration during
layout. The MOSFET pass devices should be laid out
according to the manufacturer’s guidelines for the power
being dissipated within them.
VGS = ( 4.4 − 1.575 ) = 2.825 V
So a MOSFET rated for VGS = 2.7V will be required, with
an RDS(ON)(MAX) (over temp.) given by:
RDS( ON)MAX ) =
( VIN(MIN) − VOUT )
IOUT(MAX )
=
(2.375 − 1.5)
= 22mΩ
4
Obviously, if a 12V rail is available to power the SC2738,
the number of FET options increases dramatically.
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SC2738
POWER MANAGEMENT
Typical Characteristics
PRELIMINARY
Quiescent Current vs. Junction Temperature
Standby Current vs. Junction Temperature
vs. Input Voltage
900
vs. Input Voltage
100
Both VEN = 5V
Both VADJ < VBG
800
Both VEN = 0V
VIN = 12V
700
10
VIN = 12V
IQ(OFF) (µA)
IQ (µA)
600
500
400
VIN = 5V
1
300
0.1
200
VIN = 5V
100
0
0.01
-50
-25
0
25
50
75
100
125
-50
-25
0
25
TJ (°C)
Start Threshold vs.
Junction Temperature
VIN rising
100
125
VIN = 5V
1.4
VIH
3.0
VIN falling
2.5
VIH/L (V)
VUVLO (V)
125
1.6
3.5
2.0
1.5
1.2
1.0
VIL
0.8
1.0
0.6
0.5
0.4
0.0
-50
-25
0
25
50
75
100
-50
125
-25
0
25
0.510
0.508
50
75
TJ (°C)
TJ (°C)
Reference Voltage vs.
Drive Pin Output Current (Sourcing) at Startup
Junction Temperature
vs. Junction Temperature vs. Input Voltage
20
VIN = VEN = 5V
18
0.506
16
0.504
14
0.502
12
IDRV (µA)
VADJ (mV)
100
vs. Junction Temperature
1.8
4.0
75
Enable Input Threshold Voltage
5.0
4.5
50
TJ (°C)
0.500
0.498
VEN = 5V
VADJ < VTH(PGD)
VIN = 12V
10
8
0.496
6
0.494
4
0.492
2
VIN = 5V
0
0.490
-50
-25
0
25
50
75
100
-50
125
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-25
0
25
50
75
100
125
TJ (°C)
TJ (°C)
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SC2738
POWER MANAGEMENT
Typical Characteristics (Cont.)
Drive Pin Output Current (Sourcing) vs.
Drive Pin Output Current (Sinking) vs.
Junction Temperature vs. Input Voltage
Junction Temperature vs. Input Voltage
1200
5.0
4.5
VEN = 5V
VADJ < VBG
VIN = 12V
4.0
1000
800
3.0
IDRV (µA)
IDRV (mA)
3.5
VIN = 12V
VEN = 5V
VADJ > VBG
2.5
2.0
VIN = 5V
600
400
1.5
VIN = 5V
1.0
200
0.5
0.0
0
-50
-25
0
25
50
75
100
-50
125
-25
0
25
Drive Pin Output Voltage (Full On) vs.
Junction Temperature vs. Input Voltage
-44
VIN = 5V
-46
VTH(UV) (%VADJ)
VIN = 12V
5
VDRV (V)
125
100
125
vs. Junction Temperature
VIN = VEN = 5V
-42
6
4
3
-48
-50
-52
-54
VEN = 5V
IDRV = 0mA
VADJ < VBG
-56
-58
0
-60
-50
-25
0
25
50
75
100
125
-50
-25
0
25
TJ (°C)
50
75
TJ (°C)
Power Good Threshold vs.
Power Good Logic Low Output Voltage
Junction Temperature
vs. Junction Temperature
0.0
200
VIN = VEN = 5V
175
-2.5
150
-5.0
-7.5
VPGD (mV)
VTH(PGD) (%VADJ)
100
-40
7
1
75
Under Voltage Trip Threshold
8
2
50
TJ (°C)
TJ (°C)
Startup only
-10.0
VIN = VEN = 5V
VADJ = 0.4V
IPGD = -1mA
125
100
75
50
-12.5
Normal operation
25
-15.0
0
-50
-25
0
25
50
75
100
125
-50
TJ (°C)
 2004 Semtech Corp.
-25
0
25
50
75
100
125
TJ (°C)
11
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SC2738
POWER MANAGEMENT
Typical Characteristics (Cont.)
PRELIMINARY
Output Rise Time At Startup vs. Soft Start
Capacitance vs. Input Voltage
100
VEN = 5V
TJ = 25°C
VOUT = 1.05V
COUT = 100µF, 25mΩ
IOUT = 0A
MOSFET = IRF7311
tr(OUT) (ms)
10
VIN = 5V
1
VIN = 12V
0.1
0.1
1
10
100
CDRV (nF)
Load Transient Response, No Passive Droop
Load Transient Response, With Passive Droop
VIN = 5V, 1.2V in to 1.05V out
IOUT = 0.01A to 2.51A to 0.01A
COUT = 2 x 100µF, 25mΩ
Trace 1: VOUT, 20mV/div., offset 1V
Trace 2: VDRV, 2V/div.
Trace 3: 1.2V in, 50mV/div., offset 1V
Trace 4: load FET drain
Timebase: 20µs/div.
Load rise/fall times ≥ 35A/µs
 2004 Semtech Corp.
VIN = 5V, 1.2V in to 1.05V out
IOUT = 0.01A to 2.51A to 0.01A
COUT = 1 x 100µF, 25mΩ
RDROOP = 20mΩ
Trace 1: VOUT, 20mV/div., offset 1V
Trace 2: not connected
Trace 3: 1.2V in, 50mV/div., offset 1V
Trace 4: load FET drain
Timebase: 20µs/div.
Load rise/fall times ≥ 35A/µs
12
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SC2738
POWER MANAGEMENT
Outline Drawing - MSOP-10
e
A
DIM
D
A
A1
A2
b
c
D
E1
E
e
L
L1
N
01
aaa
bbb
ccc
N
2X E/2
ccc C
2X N/2 TIPS
E
E1
PIN 1
INDICATOR
12
B
DIMENSIONS
INCHES
MILLIMETERS
MIN NOM MAX MIN NOM MAX
.043
.000
.006
.030
.037
.007
.011
.003
.009
.114 .118 .122
.114 .118 .122
.193 BSC
.020 BSC
.016 .024 .032
(.037)
10
8°
0°
.004
.003
.010
1.10
0.00
0.15
0.95
0.75
0.17
0.27
0.08
0.23
2.90 3.00 3.10
2.90 3.00 3.10
4.90 BSC
0.50 BSC
0.40 0.60 0.80
(.95)
10
0°
8°
0.10
0.08
0.25
D
aaa C
SEATING
PLANE
A2
H
A
bxN
bbb
c
GAGE
PLANE
A1
C
C A-B D
0.25
L
(L1)
DETAIL
SEE DETAIL
SIDE VIEW
01
A
A
NOTES:
1.
CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES).
2. DATUMS -A- AND -B- TO BE DETERMINED AT DATUM PLANE -H3. DIMENSIONS "E1" AND "D" DO NOT INCLUDE MOLD FLASH, PROTRUSIONS
OR GATE BURRS.
4. REFERENCE JEDEC STD MO-187, VARIATION BA.
Land Pattern - MSOP-10
X
DIM
(C)
G
Y
Z
C
G
P
X
Y
Z
DIMENSIONS
INCHES
MILLIMETERS
(.161)
.098
.020
.011
.063
.224
(4.10)
2.50
0.50
0.30
1.60
5.70
P
NOTES:
1.
THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY.
CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR
COMPANY'S MANUFACTURING GUIDELINES ARE MET.
Contact Information
Semtech Corporation
Power Management Products Division
200 Flynn Road, Camarillo, CA 93012
Phone: (805)498-2111 FAX (805)498-3804
 2004 Semtech Corp.
13
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