|
|
Número de pieza | CS5322 | |
Descripción | Two-Phase Buck Controller | |
Fabricantes | ON Semiconductor | |
Logotipo | ||
Hay una vista previa y un enlace de descarga de CS5322 (archivo pdf) en la parte inferior de esta página. Total 21 Páginas | ||
No Preview Available ! www.DataSheet4U.com
CS5322
Two−Phase Buck Controller
with Integrated Gate
Drivers and 5−Bit DAC
The CS5322 is a two−phase step down controller which
incorporates all control functions required to power high performance
processors and high current power supplies. Proprietary multi−phase
architecture guarantees balanced load current distribution and reduces
overall solution cost in high current applications. Enhanced V2™
control architecture provides the fastest possible transient response,
excellent overall regulation, and ease of use.
The CS5322 multi−phase architecture reduces output voltage and
input current ripple, allowing for a significant reduction in inductor
values and a corresponding increase in inductor current slew rate. This
approach allows a considerable reduction in input and output capacitor
requirements, as well as reducing overall solution size and cost.
Features
• Enhanced V2 Control Method
• 5−Bit DAC with 1.0% Accuracy
• Adjustable Output Voltage Positioning
• 4 On−Board Gate Drivers
• 200 kHz to 800 kHz Operation Set by Resistor
• Current Sensed through Buck Inductors, Sense Resistors, or V−S
Control
• Hiccup Mode Current Limit
• Individual Current Limits for Each Phase
• On−Board Current Sense Amplifiers
• 3.3 V, 1.0 mA Reference Output
• 5.0 V and/or 12 V Operation
• On/Off Control (through Soft Start Pin)
• Power Good Output with Internal Delay
http://onsemi.com
28
1
SO−28L
DW SUFFIX
CASE 751F
PIN CONNECTIONS AND
MARKING DIAGRAM
1
COMP
VFB
VDRP
CS1
CS2
CSREF
PWRGD
VID0
VID1
VID2
VID3
VID4
ILIM
REF
28ROSC
VCCL
VCCL1
GATE(L)1
GND
GATE(H)1
VCCH1
LGND
SS
VCCL2
GATE(L)2
GND2
GATE(H)2
VCCH2
A = Assembly Location
WL, L = Wafer Lot
YY, Y = Year
WW, W = Work Week
ORDERING INFORMATION
Device
Package
Shipping
CS5322GDW28
SO−28L 27 Units/Rail
CS5322GDWR28 SO−28L 1000 Tape & Reel
© Semiconductor Components Industries, LLC, 2006
July, 2006 − Rev. 7
1
Publication Order Number:
CS5322/D
1 page CS5322
ELECTRICAL CHARACTERISTICS (0°C < TA < 70°C; 0°C < TJ < 125°C; 4.7 V < VCCL < 14 V; 8.0 V < VCCH < 20 V;
CGATE(H) = 3.3 nF, CGATE(L) = 3.3 nF, RR(OSC) = 32.4 k, CCOMP = 1.0 nF, CSS = 0.1 μF, CREF = 0.1 μF, DAC Code 10000, CVCC = 1.0 μF,
ILIM ≥ 1.0 V; unless otherwise specified.)
Characteristic
Test Conditions
Min Typ Max Unit
Power Good Output
Power Good Fault Delay
Output Low Voltage
Output Leakage Current
Lower Threshold
CSREF = VDAC to VDAC ± 15%
CSREF = 1.0 V, IPWRGD = 4.0 mA
CSREF = 1.45 V, PWRGD = 5.5 V
% of Nominal VID Code
25 50 125 μs
−
0.25 0.40
V
− 0.1 10 μA
−14 −11 −8.0 %
Upper Threshold
% of Nominal VID Code
8 11 14 %
Voltage Feedback Error Amplifier
VFB Bias Current (Note 2)
COMP Source Current
1.0 V < VFB < 1.9 V
COMP = 0.5 V to 2.0 V;
VFB = 1.8 V; DAC = 00000
9.0 10.3 11.5 μA
15 30 60 μA
COMP Sink Current
COMP Max Voltage
COMP Min Voltage
Transconductance
Output Impedance
COMP = 0.5 V to 2.0 V;
VFB = 1.9 V; DAC = 00000
VFB = 1.8 V COMP Open; DAC = 00000
VFB = 1.9 V COMP Open; DAC = 00000
−10 μA < ICOMP < +10 μA
−
15 30 60 μA
2.4 2.7 − V
− 0.1 0.2 V
− 32 − mmho
− 2.5 − MΩ
Open Loop DC Gain
Note 3
60 90
− dB
Unity Gain Bandwidth
0.01 μF COMP Capacitor
− 400 − kHz
PSRR @ 1.0 kHz
− − 70 − dB
Soft Start
Soft Start Charge Current
0.2 V ≤ SS ≤ 3.0 V
15 30 50 μA
Soft Start Discharge Current
0.2 V ≤ SS ≤ 3.0 V
4.0 7.5 13 μA
Hiccup Mode Charge/Discharge Ratio
−
3.0 4.0 − −
Peak Soft Start Charge Voltage
− 3.3 4.0 4.2 V
Soft Start Discharge Threshold Voltage
−
0.20 0.27 0.34
V
PWM Comparators
Minimum Pulse Width
Channel Start Up Offset
Measured from CSx to GATE(H)X
V(VFB) = V(CSREF) = 1.0 V, V(COMP) = 1.5 V
60 mV step applied between VCSX and VCREF
−
350 515 ns
V(CS1) = V(CS2) = V(VFB) = V(CSREF) = 0 V;
0.3
0.4
0.5
V
Measure V(COMP) when GATE(H)1,
GATE(H)2, switch high
GATE(H) and GATE(L)
High Voltage (AC)
Note 3 Measure VCCLX − GATE(L)X or
VCCHX − GATE(H)X
Low Voltage (AC)
Note 3 Measure GATE(L)X or GATE(H)X
Rise Time GATE(H)X
1.0 V < GATE < 8.0 V; VCCHX = 10 V
Rise Time GATE(L)X
1.0 V < GATE < 8.0 V; VCCLX = 10 V
2. The VFB Bias Current changes with the value of ROSC per Figure 4.
− 0 1.0 V
− 0 0.5 V
− 35 80 ns
− 35 80 ns
http://onsemi.com
5
5 Page CS5322
APPLICATIONS INFORMATION
FIXED FREQUENCY MULTI−PHASE CONTROL
In a multi−phase converter, multiple converters are
connected in parallel and are switched on at different times.
This reduces output current from the individual converters
and increases the apparent ripple frequency. Because several
converters are connected in parallel, output current can ramp
up or down faster than a single converter (with the same
value output inductor) and heat is spread among multiple
components.
The CS5322 uses a two−phase, fixed frequency,
Enhanced V2 architecture. Each phase is delayed 180° from
the previous phase. Normally Gate(H) transitions high at the
beginning of each oscillator cycle. Inductor current ramps
up until the combination of the current sense signal and the
output ripple trip the PWM comparator and bring Gate(H)
low. Once Gate(H) goes low, it will remain low until the
beginning of the next oscillator cycle. While Gate(H) is
high, the enhanced V2 loop will respond to line and load
transients. Once Gate(H) is low, the loop will not respond
again until the beginning of the next cycle. Therefore,
constant frequency Enhanced V2 will typically respond
within the off−time of the converter.
The Enhanced V2 architecture measures and adjusts
current in each phase. An additional input (Cx) for inductor
current information has been added to the V2 loop for each
phase as shown in Figure 9.
SWNODE L
RL
RS
VOUT
+
CX +CSA
+
OFFSET
CSREF
+
+
VFB
DACOUT
E+.A.
+ COMP
PWM-
COMP
+
Figure 9. Enhanced V2 Feedback and Current
Sense Scheme
The inductor current is measured across RS, amplified by
CSA and summed with the OFFSET and Output Voltage at
the non−inverting input of the PWM comparator. The
inductor current provides the PWM ramp and as inductor
current increases the voltage on the positive pin of the PWM
comparator rises and terminates the PWM cycle. If the
inductor starts the cycle with a higher current, the PWM
cycle will terminate earlier providing negative feedback.
The CS5322 provides a Cx input for each phase, but the
CSREF, VFB and COMP inputs are common to all phases.
Current sharing is accomplished by referencing all phases to
the same VFB and COMP pins, so that a phase with a larger
current signal will turn off earlier than phases with a smaller
current signal.
Including both current and voltage information in the
feedback signal allows the open loop output impedance of
the power stage to be controlled. When the average output
current is zero, the COMP pin will be only 1/2 of the steady
state ramp height plus the OFFSET above the output
voltage. If the COMP pin is held steady and the inductor
current changes, there must also be a change in the output
voltage. Or, in a closed loop configuration when the output
current changes, the COMP pin must move to keep the same
output voltage. The required change in the output voltage or
COMP pin depends on the scaling of the current feedback
signal and is calculated as
DV + RS CSA Gain DI
The single−phase power stage output impedance is:
Single Stage Impedance + DVńDI + RS CSA Gain.
The multi−phase power stage output impedance is the
single−phase output impedance divided by the number of
phases. The output impedance of the power stage determines
how the converter will respond during the first few μs of a
transient before the feedback loop has repositioned the
COMP pin.
The peak output current of each phase can also be
calculated from;
Ipkout
(per
phase)
+
VCOMP *
RS
VFB * VOFFSET
CSA Gain
Figure 10 shows the step response of a single phase with
the COMP pin at a fixed level. Before T1 the converter is in
normal steady state operation. The inductor current provides
the PWM ramp through the Current Sense Amplifier. The
PWM cycle ends when the sum of the current signal, voltage
signal and OFFSET exceed the level of the COMP pin. At
T1 the output current increases and the output voltage sags.
The next PWM cycle begins and the cycle continues longer
than previously while the current signal increases enough to
make up for the lower voltage at the VFB pin and the cycle
ends at T2. After T2 the output voltage remains lower than
at light load and the current signal level is raised so that the
sum of the current and voltage signal is the same as with the
original load. In a closed loop system the COMP pin would
http://onsemi.com
11
11 Page |
Páginas | Total 21 Páginas | |
PDF Descargar | [ Datasheet CS5322.PDF ] |
Número de pieza | Descripción | Fabricantes |
CS5320 | 24-Bit Variable Bandwidth A/D Converter Chipset | Cirrus Logic |
CS5320-KL | 24-Bit Variable Bandwidth A/D Converter Chipset | Cirrus Logic |
CS5320-KL1 | 24-Bit Variable Bandwidth A/D Converter Chipset | Cirrus Logic |
CS5321 | 24-Bit Variable Bandwidth A/D Converter Chipset | Cirrus Logic |
Número de pieza | Descripción | Fabricantes |
SLA6805M | High Voltage 3 phase Motor Driver IC. |
Sanken |
SDC1742 | 12- and 14-Bit Hybrid Synchro / Resolver-to-Digital Converters. |
Analog Devices |
DataSheet.es es una pagina web que funciona como un repositorio de manuales o hoja de datos de muchos de los productos más populares, |
DataSheet.es | 2020 | Privacy Policy | Contacto | Buscar |