SC1182/3 DESCRIPTION SC1182/3 combines synchronous voltage m
|
|
|
Top Searches for this datasheet
PROGRAMMABLE SYNCHRONOUS DC/DC CONVERTER, DUAL DROPOUT REGULATOR CONTROLLER
SC1182/3
DESCRIPTION
SC1182/3 combines synchronous voltage mode controller with low-dropout linear regulators providing most circuitry necessary implement three DC/DC converters powering advanced microprocessors such Pentium (Klamath) Deschutes. SC1182/3 switching section features integrated converter, pulse pulse current limiting, integrated power good signaling, logic compatible shutdown. SC1182/3 switching section operates fixed frequency 200kHz, providing optimum compromise between size, efficiency cost intended application areas. integrated converter provides programmability output voltage from 2.0V 3.5V 100mV increments 1.30V 2.05V 50mV increments with external components. SC1182/3 linear sections dropout regulators. SC1182 supplies 1.5V 2.5V non-GTL I/O. SC1183 both LDO's adjustable.
FEATURES
Synchronous design, enables heatsink solution efficiency (switching section) output programmability chip power good function Designed Intel Pentium VRM8.1 requirements 1.5V, 2.5V Adj. linear section
APPLICATIONS
Pentium Deschutes microprocessor supplies Flexible motherboards 1.3V 3.5V microprocessor supplies Programmable triple power supplies
ORDERING INFORMATION
Part Number
Package
Linear Voltage
Temp. Range
SC1182CSW SC1183CSW
SO-24 SO-24
1.5V/2.5V 125°C Adj. 125°C
Note: suffix `TR' tape reel.
CONFIGURATION
BLOCK DIAGRAM
REF.
View
AGND GATE1 LDOS1 LDOS2 PWRGOOD CSCS+ PGNDH PGNDL
GATE2 LDOV VID0 VID1 VID2 VID3 VID4 VOSENSE BSTH BSTL
SOIC)
CONTROLLER 2.5V/ADJ.
1.265V REF.
CONTROLLER 1.5V/ADJ.
LDOV
Pentium registered trademark Intel Corporation
1998 SEMTECH CORP.
MITCHELL ROAD NEWBURY PARK 91320
PROGRAMMABLE SYNCHRONOUS DC/DC CONVERTER, DUAL DROPOUT REGULATOR CONTROLLER
SC1182/3
ABSOLUTE MAXIMUM RATINGS
Parameter PGND Operating Temperature Range Junction Temperature Range Storage Temperature Range Lead Temperature (Soldering) seconds Thermal Impedance Junction Ambient Thermal Impedance Junction Case Symbol Maximum -0.3 -0.3 +125 +150 Units °C/W °C/W
TSTG
ELECTRICAL CHARACTERISTICS
Unless specified: 4.75V 5.25V; PGND VOSENSE (CSp-CSm) 60mV; LDOV 11.4V 12.6V; 25°C
PARAMETER Switching Section Output Voltage Supply Voltage Supply Current Load Regulation Line Regulation Minimum operating voltage Current Limit Voltage Oscillator Frequency Oscillator Duty Cycle Peak Sink/Source Current Peak Sink/Source Current Output Voltage Tempco Gain (AOL) threshold voltage source current Power good threshold voltage Dead time Linear Sections Quiescent current Output Voltage (LDO1 SC1182) Output Voltage (LDO2 SC1182) Reference Voltage (SC1183) Feedback Bias Current (SC1183) Gain (AOL) Load Regulation Line Regulation Output Impedance Notes: Output Voltage table. application circuit. 1998 SEMTECH CORP.
CONDITIONS 0.8A
UNITS
BSTH-DH 4.5V, DH-PGNDH BSTL-DL 4.5V, DL-PGNDL VOSENSE VOVP 3.0V
Note 2.475 2.500 2.525 1.485 1.500 1.515 1.252 1.265 1.278
ppm/
LDOV
LDOS (1,2) GATE (1,2)
MITCHELL ROAD NEWBURY PARK 91320
PROGRAMMABLE SYNCHRONOUS DC/DC CONVERTER, DUAL DROPOUT REGULATOR CONTROLLER
SC1182/3
DESCRIPTION
Name AGND GATE1 LDOS1 LDOS2 PWRGOOD CSCS+ PGNDH PGNDL BSTL BSTH VOSENSE VID4 VID3 VID2 VID1 VID0 LDOV GATE2 Function Small Signal Analog Digital Ground Gate Drive Output LDO1 Sense Input LDO1 Sense Input LDO2 Input Voltage High Signal VO>setpoint +20% Open collector logic output, high within setpoint Current Sense Input (negative) Current Sense Input (positive) Power Ground High Side Switch High Side Driver Output Power Ground Side Switch Side Driver Output Supply Side Driver Supply High Side Driver Logic shuts down converter; High open normal operation. internal feedback chain Programming Input (MSB) Programming Input Programming Input Programming Input Programming Input (LSB) +12V section Gate Drive Output LDO2
View
AGND GATE1 LDOS1 LDOS2 PWRGOOD CSCS+ PGNDH PGNDL GATE2 LDOV VID0 VID1 VID2 VID3 VID4 VOSENSE BSTH BSTL
SOIC)
Note: logic level inputs outputs open collector compatible.
1998 SEMTECH CORP. MITCHELL ROAD NEWBURY PARK 91320
PROGRAMMABLE SYNCHRONOUS DC/DC CONVERTER, DUAL DROPOUT REGULATOR CONTROLLER
SC1182/3
OUTPUT VOLTAGE
Unless specified: 4.75V 5.25V; PGND VOSENSE (CSp-CSm) 60mV; 25°C
PARAMETER Output Voltage
CONDITIONS Application circuit
43210 01111 01110 01101 01100 01011 01010 01001 01000 00111 00110 00101 00100 00011 00010 00001 00000 11111 11110 11101 11100 11011 11010 11001 11000 10111 10110 10101 10100 10011 10010 10001 10000
1.287 1.336 1.386 1.435 1.485 1.534 1.584 1.633 1.683 1.732 1.782 1.831 1.881 1.930 1.980 2.029 1.980 2.079 2.178 2.277 2.376 2.475 2.574 2.673 2.772 2.871 2.970 3.069 3.168 3.267 3.366 3.465
1.300 1.350 1.400 1.450 1.500 1.550 1.600 1.650 1.700 1.750 1.800 1.850 1.900 1.950 2.000 2.050 2.000 2.100 2.200 2.300 2.400 2.500 2.600 2.700 2.800 2.900 3.000 3.100 3.200 3.300 3.400 3.500
1.313 1.364 1.414 1.465 1.515 1.566 1.616 1.667 1.717 1.768 1.818 1.869 1.919 1.970 2.020 2.071 2.020 2.121 2.222 2.323 2.424 2.525 2.626 2.727 2.828 2.929 3.030 3.131 3.232 3.333 3.434 3.535
UNITS
1998 SEMTECH CORP. MITCHELL ROAD NEWBURY PARK 91320
0.1uF
CSVO SENSE PWRGOOD VID4 VID0 VID1 VID2
1.00k 2.32k
1998 SEMTECH CORP.
APPLICATION CIRCUIT
0.1uF
1500uF 1500uF 1500uF 1500uF BUK556 5mOhm 1500uF 1500uF BUK556
VID3 AGND PGNDL GATE2 GATE1 LDOS2 LDOS1 LDOV BSTL PGNDH BSTH
VCC_CORE
0.1uF
0.1uF
VID0
VID1
VID2
VID3
VID4 SC1182/3CSW
VLIN1 BUK556
PWRGD
100K 330uF 330uF VLIN2
BUK556 330uF
PROGRAMMABLE SYNCHRONOUS DC/DC CONVERTER, DUAL DROPOUT REGULATOR CONTROLLER
330uF
330uF
NOTE: SC1182, R12,R13,R14 REQUIRED. CONNECT LDOS1 (PIN3) LDOS2 (PIN4) VLIN1 VLIN2 RESPECTIVELY DIRECTLY GENERATE 2.5V 1.5V OUTPUTS. "SETTING OUTPUT VOLTAGE" TABLE 100K
330uF
SC1182/3
MITCHELL ROAD NEWBURY PARK 91320
PROGRAMMABLE SYNCHRONOUS DC/DC CONVERTER, DUAL DROPOUT REGULATOR CONTROLLER
SC1182/3
MATERIALS LIST
Qty. Reference C1,C5,C13, C2,C3,C14C17 C9-C12, C21, Q1,Q2,Q3, R17, Part/Description 0.1µF Ceramic 1500µF/6.3V 330µF/6.3V notes 2.32k, 1/8W 1/8W 1/8W 1/8W 1/8W 1/8W 1/8W 100K, 1/8W SC1182/3CSW notes Various Various Various Various Various Various Various Various SEMTECH Table Below (Not required SC1182) Table Below (Not required SC1182) Table Below (Not required SC1182) Table Below (Not required SC1182) Vendor Various SANYO Various Turns 16AWG MICROMETALS T50-52D core selection requires trade-off between efficiency cost. Absolute maximum RDS(ON) Q1,Q2 OAR-1 Series MV-GX equiv. Notes
SETTING OUTPUT VOLTAGE
VOUT LDO1 (LDO2) 3.45V 3.30V 3.10V 2.90V 2.80V 2.50V 1.50V (R14) (R15) 97.6 18.7
VOUT
1.265 (IFB
Where Feedback bias current feedback resistor Bottom feedback resistor layout diagram clarification must enough that (IFB term does cause significan error
1998 SEMTECH CORP.
MITCHELL ROAD NEWBURY PARK 91320
PROGRAMMABLE SYNCHRONOUS DC/DC CONVERTER, DUAL DROPOUT REGULATOR CONTROLLER
SC1182/3
Efficiency
Efficiency
3.5V 3.5V Sync 3.5V Sync
2.8V 2.8V Sync 2.8V Sync
(Amps)
(Amps)
Typical Efficiency Vo=3.5V
Typical Efficiency Vo=2.8V
Efficiency
Efficiency
2.5V 2.5V Sync 2.5V Sync
2.0V 2.0V Sync 2.0V Sync
(Amps)
(Amps)
Typical Efficiency Vo=2.5V
Typical Efficiency Vo=2.0V
Typical Ripple, Vo=2.8V, Io=10A
Transient Response Vo=2.8V, Io=300mA
1998 SEMTECH CORP. MITCHELL ROAD NEWBURY PARK 91320
PROGRAMMABLE SYNCHRONOUS DC/DC CONVERTER, DUAL DROPOUT REGULATOR CONTROLLER
SC1182/3
LAYOUT GUIDELINES
Careful attention layout requirements necessary successful implementation SC1182/3 controller. High currents switching 200kHz present application their effect ground plane voltage differentials must understood minimized. high power parts circuit should laid first. ground plane should used, number position ground plane interruptions should such unnecessarily compromise ground plane integrity. Isolated semi-isolated areas ground plane deliberately introduced constrain ground currents particular areas, example input capacitor bottom ground. loop formed Input Capacitor(s) (Cin), (Q1) Bottom (Q2) must kept
small possible. This loop contains high current, fast transition switching. Connections should wide short possible minimize loop inductance. Minimizing this loop area will reduce EMI, lower ground injection currents, resulting electrically "cleaner" grounds rest system minimize source ringing, resulting more reliable gate switching signals. connection between junction output inductor should wide trace copper region. should short practical. Since this connection fast voltage transitions, keeping this connection short will minimize EMI. connection between output inductor sense resistor should wide trace copper area, there fast voltage current transitions this connection length important, however adding unnecessary impedance will reduce efficiency.
0.1uF 0.1uF
AGND GATE1 LDOS1 LDOS2 PWRGOOD CSCS+ PGNDH PGNDL GATE2 LDVO VID0 VID1 VID2 VID3 VID4 SENSE BSTH BSTL
Cout 1.00k 5mOhm Vout 2.32k
SC1182/3
Heavy lines indicate
Cout Lin1 Lin1
high current paths.
SC1182, RA1, RA2, required. LDOS1 connects Lin1, LDOS2 connects Lin2
Lin2
Cout Lin2
Layout diagram SC1182/3
1998 SEMTECH CORP. MITCHELL ROAD NEWBURY PARK 91320
PROGRAMMABLE SYNCHRONOUS DC/DC CONVERTER, DUAL DROPOUT REGULATOR CONTROLLER
August 1998 Output Capacitor(s) (Cout) should located close load possible, fast transient load currents supplied Cout only, connections between Cout load must short, wide copper areas minimize inductance resistance. SC1182/3 best placed over quiet ground plane area, avoid pulse currents Cin, loop flowing this area. PGNDH PGNDL should returned ground plane close package. AGND should connected ground side (one output capacitor(s). this possible, AGND connected ground path between Output Capacitor(s) Cin, loop. Under circumstances should AGND returned ground inside Cin, loop. SC1182/3 should supplied from
SC1182/3
supply through resistor, should decoupled directly AGND 0.1µF ceramic capacitor, trace lengths should short possible. Current Sense resistor divider across should form small loop possible, traces running back SC1182/3 should parallel close each other. 0.1µF capacitor should mounted close pins possible. Ideally, grounds sections should returned ground side (one output capacitor(s).
Vout
Currents various parts power section
1998 SEMTECH CORP. MITCHELL ROAD NEWBURY PARK 91320
PROGRAMMABLE SYNCHRONOUS DC/DC CONVERTER, DUAL DROPOUT REGULATOR CONTROLLER
SC1182/3
fast enough reduce voltage dropped across faster rate than capacitor sags, hence enSWITCHING SECTION suring good recovery from transient with additional OUTPUT CAPACITORS Selection begins with excursions. most critical component. Because fast transient load must also concerned with ripple current current requirements modern microprocessor core output inductor general rule thumb been supplies, output capacitors must supply transient allow maximum output current ripple current. load current requirements until current output Note that most output voltage ripple produced inductor ramps level. Output capacitor inductor ripple current flowing output caESR therefore most important criteria. pacitor ESR. Ripple current calculated from: maximum simply calculated from:
COMPONENT SELECTION
ILRIPPLE=
fOSC
Where Maximum transient voltage excursion Transient current step
example, meet 100mV transient limit with load step, output capacitor must less than 10m. meet this kind level, there three available capacitor technologies.
Each Capacitor Technology Tantalum OS-CON Aluminum (µF) 1500 Qty. Rqd. Total (µF) 2000 7500
Ripple current allowance will define minimum permitted inductor value. POWER FETS FETs chosen based several criteria with probably most important being power dissipation power handling capability. power dissipation combination conduction losses, switching losses bottom body diode recovery losses. Conduction losses simply calculated
PCOND where duty cycle
Switching losses estimated assuming switching time, assume 100ns then:
choice which simply cost/performance issue, with Aluminum being cheapest, taking most space. INDUCTOR Having decided suitable type value output capacitor, maximum allowable value inductor calculated. large inductor will produce slow current ramp rate will cause output capacitor supply more transient load current longer leading output voltage below excursion calculated above. maximum inductor value calculated from:
more generally,
(VIN
Body diode recovery losses more difficult estimate, first approximation, reasonable assume that stored charge bottom body diode will moved through starts turn resulting power dissipation will
first order approximation, convenient only consider conduction losses determine suitability. 2.8V 14.2A requirement, typical losses would
calculated maximum inductor value assumes 100% duty cycle, some allowance must made. Choosing inductor value calculated maximum will guarantee that inductor current will ramp
1998 SEMTECH CORP. MITCHELL ROAD NEWBURY PARK 91320
PROGRAMMABLE SYNCHRONOUS DC/DC CONVERTER, DUAL DROPOUT REGULATOR CONTROLLER
August 1998 type RDS(on) 2.48 0.79 1.53 Package TO220 SO-8
SC1182/3
BUK556H IRL2203 Si4410 13.5
BOTTOM Bottom losses almost entirely conduction. body diode forced into conduction beginning bottom switch conduction period, when turns off, there very little voltage across resulting switching losses. Conduction losses determined
PCOND
INPUT CAPACITORS since ripple current input capacitors high output current, suitable capacitors must chosen accordingly. Also, during fast load transients, there restrictions input di/dt. These restrictions require useable energy storage within converter circuitry, either extra output capacitance more usually, additional input capacitors. Choosing input capacitors will help maximize ripple rating given size.
example above: type RDS(on) 1.95 0.62 1.20 13.5 Package TO220 SO-8
BUK556H IRL2203 Si4410
Each package types characteristic thermal impedance, TO-220 package, thermal impedance mostly determined heatsink used. surface mount packages double sided FR4, printed circuit board material, thermal impedances SO-8 readily achievable. corresponding temperature rise detailed below: Temperature rise type IRL2203 Si4410
Bottom 39.0
BUK556H 49.6
31.6 122.4
24.8
With Heatsink apparent that single SO-8 Si4410 adequate this application, using parallel pairs each position, power dissipation will approximately halved temperature rise reduced factor
1998 SEMTECH CORP. MITCHELL ROAD NEWBURY PARK 91320
PROGRAMMABLE SYNCHRONOUS DC/DC CONVERTER, DUAL DROPOUT REGULATOR CONTROLLER
SC1182/3
OUTLINE DRAWING
JEDEC MS-013AD B17104B
1998 SEMTECH CORP. MITCHELL ROAD NEWBURY PARK 91320
Other recent searches
SY100 - SY100 SY100 Datasheet
MRS16S - MRS16S MRS16S Datasheet
MBRS410LT3 - MBRS410LT3 MBRS410LT3 Datasheet
GP1A046RBZLF - GP1A046RBZLF GP1A046RBZLF Datasheet
ELLM-2182WB - ELLM-2182WB ELLM-2182WB Datasheet
HRC-6 - HRC-6 HRC-6 Datasheet
DBS800 - DBS800 DBS800 Datasheet
BSC077N12NS3 - BSC077N12NS3 BSC077N12NS3 Datasheet
Privacy Policy | Disclaimer
© 2012 Datasheet Archive
