sc1175 Semtech Corporation, sc1175 Datasheet - Page 5

• Manufacturer Part Number: sc1175
• Description: Sc1175 Low-power Dual Synchronous Dc/dc Controller With Current-sharing Circuitry
• Manufacturer: Semtech Corporation

Expanded Pin Description
Expanded Pin Description
Pin 1:
Pin 1:
Pin 2:
Pin 2:
Pin 3, 18:
Pin 3, 18:
Pin 4:
Pin 4:
Pin 5, 6,
Pin 5, 6,
Pin 7, 14:
Pin 7, 14:
Pin 8, 13:
Pin 8, 13:
POWER MANAGEMENT
Expanded Pin Description
Expanded Pin Description
Expanded Pin Description
Pin 1:
Pin 1:
Pin 1: (VREF)
Internal 1.25V reference
Connected to the + input of the master channel error
amplifier.
Pin 2:
Pin 2:
Pin 2: (+IN)
+ Input of slave channel error amplifier.
Connected to 1.25V reference (Pin 1) for the two
independent channel configuration.
Pin 3, 18:
Pin 3, 18:
Pin 3, 18: (-IN2, -IN1)
- Inputs of close loop error amplifiers.
Works as a feedback inputs (For both modes).
Pin 4:
Pin 4:
Pin 4: (VCC)
VCC chip supply voltage.
15V maximum, 10mA typical.
Needs a 1µF ceramic multilayer decoupling capacitor
to GND (Pin 20).
Pin 5, 6,
Pin 5, 6,1 1 1 1 1 5, 1
Pin 5, 6,
Pins (-) and (+) of the current limit amplifiers for both
channels.
Connected to output current sense resistors. Com-
pares that sense voltage to internal 75mV reference.
Needs RC filter for noise rejection.
Pin 7, 14:
Pin 7, 14:
Pin 7, 14: (BST2, BST1)
BST signal. Supply for high side driver.
Can be connected to a high enough voltage source.
Usually connected to bootstrap circuit.
Pin 8, 13:
Pin 8, 13:
Pin 8, 13: (DH2, DH1)
DH signal (Drive High).
Gate drive for top MOSFETs.
Requires a small series resistor.
Pin Configuration
Pin Descriptions
2004 Semtech Corp.
5, 1
5, 1
5, 1
5, 16: 6: 6: 6: 6: (CL2-, CL2+, CL1+, CL1-)
(SOIC-20 and TSSOP-20 Pin)
Top View
5
Pin 9, 12:
Pin 9, 12:
Pin 10:
Pin 10:
Pin 11:
Pin 11:
Pin 1
Pin 1
Pin 19:
Pin 19:
Pin 20:
Pin 20:
Notes:
(1) Only available in tape and reel packaging. A reel
contains 1000 (SOIC) and 2500 (TSSOP) devices.
(2) Lead free product. This product is fully WEEE and
RoHS compliant.
Pin 9, 12:
Pin 9, 12: (DL2, DL1)
Pin 9, 12:
DL signal (Drive Low).
Gate drive for bottom MOSFETs.
Requires a small series resistor.
Pin 10:
Pin 10:
Pin 10: (PGND)
Power GND. Return of gate drive currents.
Pin 11:
Pin 11:
Pin 11: (BSTC)
Supply for bottom MOSFETs gate drive.
Pin 1
Pin 17 7 7 7 7 : : : : : (SS/ENA)
Pin 1
Soft start pin. Internal current source connected to
external capacitor.
Inhibits the chip if pulled down.
Pin 19:
Pin 19:
Pin 19: (PWRGD)
Power good signal.
Open collector signal .
Turns to 0 if output voltage is outside the power good
window.
Pin 20:
Pin 20:
Pin 20: (GND)
Analog GND.
Ordering Information
S
S
S
S
S
S
C
C
C
C
C
C
1
1
1
1
1
1
1
1
1
1
1
1
D
7
7
7
7
7
7
5
5
5
5
5
5
e
C
C
T
T
E
E
v
S
S
V
V
c i
S
S
T .
T
B
B
W
W
e
R
R
1 -
2 -
(
) 1
T .
T
T
R
(
R
) 2
T
(
) 2
C
D
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l a
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t n
C
h
S
a
h
n
a
T
n
P
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S
l e
S
a
B
B
O
S
V
V
c
o
o
C I
O
k
e
e
a
a
P
a
s r
s r
2 -
d r
d r
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2 -
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www.semtech.com
SC1175
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