參數(shù)資料
型號(hào): HIP6004A
廠商: Intersil Corporation
英文描述: Buck Pulse-Width Modulator (PWM) Controller and Output Voltage Monitor(脈沖帶寬調(diào)節(jié)控制和輸出電壓檢測(cè)電路)
中文描述: 降壓脈寬調(diào)制(PWM)控制器和輸出電壓監(jiān)視器(脈沖帶寬調(diào)節(jié)控制和輸出電壓檢測(cè)電路)
文件頁(yè)數(shù): 10/12頁(yè)
文件大?。?/td> 159K
代理商: HIP6004A
2-71
case response time. With a +12V input, and output voltage
level equal to DACOUT, t
FALL
is the longest response time.
Input Capacitor Selection
Use a mix of input bypass capacitors to control the voltage
overshoot across the MOSFETs. Use small ceramic
capacitors for high frequency decoupling and bulk capacitors
to supply the current needed each time Q
1
turns on. Place
the small ceramic capacitors physically close to the
MOSFETs and between the drain of Q
1
and the source of
Q
2
.
The important parameters for the bulk input capacitor are the
voltage rating and the RMS current rating. For reliable
operation, select the bulk capacitor with voltage and current
ratings above the maximum input voltage and largest RMS
current required by the circuit. The capacitor voltage rating
should be at least 1.25 times greater than the maximum
input voltage and a voltage rating of 1.5 times is a
conservative guideline. The RMS current rating requirement
for the input capacitor of a buck regulator is approximately
1/2 the DC load current.
For a through hole design, several electrolytic capacitors
(Panasonic HFQ series or Nichicon PL series or Sanyo
MV-GX or equivalent) may be needed. For surface mount
designs, solid tantalum capacitors can be used, but caution
must be exercised with regard to the capacitor surge current
rating. These capacitors must be capable of handling the
surge-current at power-up. The TPS series available from
AVX, and the 593D series from Sprague are both surge
current tested.
MOSFET Selection/Considerations
The HIP6004A requires 2 N-Channel power MOSFETs.
These should be selected based upon r
DS(ON)
, gate supply
requirements, and thermal management requirements.
In high-current applications, the MOSFET power dissipation,
package selection and heatsink are the dominant design
factors. The power dissipation includes two loss
components; conduction loss and switching loss. The
conduction losses are the largest component of power
dissipation for both the upper and the lower MOSFETs.
These losses are distributed between the two MOSFETs
according to duty factor (see the equations below). Only the
upper MOSFET has switching losses, since the Schottky
rectifier clamps the switching node before the synchronous
rectifier turns on. These equations assume linear voltage-
current transitions and do not adequately model power loss
due the reverse-recovery of the lower MOSFET’s body
diode. The gate-charge losses are dissipated by the
HIP6004A and don't heat the MOSFETs. However, large
gate-charge increases the switching interval, t
SW
which
increases the upper MOSFET switching losses. Ensure that
both MOSFETs are within their maximum junction
temperature at high ambient temperature by calculating the
temperature rise according to package thermal-resistance
specifications. A separate heatsink may be necessary
depending upon MOSFET power, package type, ambient
temperature and air flow.
Standard-gate MOSFETs are normally recommended for
use with the HIP6004A. However, logic-level gate MOSFETs
can be used under special circumstances. The input voltage,
upper gate drive level, and the MOSFET’s absolute gate-to-
source voltage rating determine whether logic-level
MOSFETs are appropriate.
Figure 9 shows the upper gate drive (BOOT pin) supplied by
a bootstrap circuit from V
CC
. The boot capacitor, C
BOOT
develops a floating supply voltage referenced to the PHASE
pin. This supply is refreshed each cycle to a voltage of V
CC
less the boot diode drop (V
D
) when the lower MOSFET, Q
2
turns on. Logic-level MOSFETs can only be used if the
MOSFET’s absolute gate-to-source voltage rating exceeds
the maximum voltage applied to V
CC
.
Figure 10 shows the upper gate drive supplied by a direct
connection to V
CC
. This option should only be used in
converter systems where the main input voltage is +5V
DC
or less. The peak upper gate-to-source voltage is
approximately V
CC
less the input supply. For +5V main
power and +12V
DC
for the bias, the gate-to-source voltage
of Q
1
is 7V. A logic-level MOSFET is a good choice for Q
1
and a logic-level MOSFET can be used for Q
2
if its
absolute gate-to-source voltage rating exceeds the
maximum voltage applied to V
CC
.
P
UPPER
= Io
2
x r
DS(ON)
x D +1
P
LOWER
= Io
2
x r
DS(ON)
x (1 - D)
2Io x V
IN
x t
SW
x F
S
Where: D is the duty cycle = V
OUT
/ V
IN
,
t
SW
is the switch ON time, and
F
S
is the switching frequency.
+12V
PGND
HIP6004A
GND
LGATE
UGATE
PHASE
BOOT
V
CC
+5V OR +12V
NOTE:
V
G-S
V
CC
-V
D
NOTE:
V
G-S
V
CC
C
BOOT
D
BOOT
Q1
Q2
+
-
FIGURE 9. UPPER GATE DRIVE - BOOTSTRAP OPTION
D2
+ V
D
-
HIP6004A
相關(guān)PDF資料
PDF描述
HIP6004ACB Buck and Synchronous-Rectifier (PWM) Controller and Output Voltage Monitor
HIP6004B Buck and Synchronous-Rectifier (PWM) Controller and Output Voltage Monitor(脈沖帶寬調(diào)節(jié)控制和輸出電壓檢測(cè)電路)
HIP6004 Buck and Synchronous-Rectifier (PWM) Controller and Output Voltage Monitor(脈沖帶寬調(diào)節(jié)控制和輸出電壓檢測(cè)電路)
HIP6004CB Buck and Synchronous-Rectifier (PWM) Controller and Output Voltage Monitor
HIP6005A Buck Pulse-Width Modulator (PWM) Controller and Output Voltage Monitor(脈沖帶寬調(diào)節(jié)控制和輸出電壓檢測(cè)電路)
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
HIP6004A_02 制造商:INTERSIL 制造商全稱:Intersil Corporation 功能描述:Buck and Synchronous-Rectifier (PWM) Controller and Output Voltage Monitor
HIP6004ACB 制造商:Rochester Electronics LLC 功能描述:- Bulk 制造商:Harris Corporation 功能描述:SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, PDSO20 制造商:Intersil Corporation 功能描述:
HIP6004ACB-T 制造商:Rochester Electronics LLC 功能描述:- Tape and Reel 制造商:Harris Corporation 功能描述:
HIP6004B 制造商:INTERSIL 制造商全稱:Intersil Corporation 功能描述:Buck and Synchronous-Rectifier (PWM) Controller and Output Voltage Monitor
HIP6004B_03 制造商:INTERSIL 制造商全稱:Intersil Corporation 功能描述:Buck and Synchronous-Rectifier (PWM) Controller and Output Voltage Monitor