- 您现在的位置：买卖IC网 > PDF目录192315 > SC1146CSW (Semtech Corporation) VRM9.0 PROGRAMMABLE, MULTI-PHASE, HIGH PERFORMANCE PWM CONTROLLER PDF资料下载
参数资料
| 型号： | SC1146CSW |
| 厂商： | Semtech Corporation |
| 英文描述： | VRM9.0 PROGRAMMABLE, MULTI-PHASE, HIGH PERFORMANCE PWM CONTROLLER |
| 中文描述： | VRM9.0可编程多相位，高性能的PWM控制器 |
| 文件页数： | 10/10页 |
| 文件大小： | 148K |
| 代理商： | SC1146CSW |
VRM9.0 PROGRAMMABLE, MULTI-PHASE,
HIGH PERFORMANCE PWM CONTROLLER
SC1146
2000 SEMTECH CORP.
652 MITCHELL ROAD NEWBURY PARK CA 91320
July 25, 2000
9
The SC1146 is patent pending
The error amplifier has two inverting inputs, one for the
High Range, (VID4 set to logic high) and one input for
the Low Range. The effective gain of the error ampli-
fier stays constant in both ranges keeping the loop gain
constant regardless of output voltage range.
BANDGAP REFERENCE/SOFT START
The precision internal bandgap reference provides a
stable, temperature compensated 2.05 V reference for
the error amplifier’s non-inverting input, the DAC
REF for
the VID digital to analog converter, the under-voltage
lock-out circuitry as well as the reference for the Bias
generator current sources. The error amplifiers non-
inverting input is connected to the bandgap reference
through a 3Kohm resistor, which is also externally con-
nected to a soft-start capacitor via the BG
OUT pin. Upon
application of power, the non-inverting input of the er-
ror amplifier is held low for a short time, set by the RC
product of the soft-start capacitor and 3Kohm, allowing
for the decoder and PWM controller to settle. This pre-
vents any harmful output voltage overshoots upon start
up or after a converter shut-down (as a result of over-
current or the enable pin pulled low). The non-inverting
input then ramps up according to the RC time constant
allowing gradual rise of output voltage.
OVER-CURRENT COMPARATOR
The SC1146 has an internal over-current comparator
designed to sense current in the input supply path.
The comparator inputs have a high common voltage
range thus allowing operation under all possible volt-
age/current combinations. The output of the compara-
tor pulls the BG
OUT (soft start) pin low thus disabling the
error amplifier and causing the PWM outputs to enter
minimum duty cycle mode, regulating the output at a
minimum voltage. A current sense trace may be used
as the current sense resistor. This will utilize the trace
as input filter inductor, thus preventing conducted
emissions to input supply. For details of programming
the overcurrent comparator, refer to SC1144-EVB user
manual.
SC1146 Special features:
The SC1146 is a special version of the original
SC1144, 4-phase PWM controller, with the latest
VRM9.0 VID codes which allow programming lower
output voltages required by the latest Microprocessors.
Also a +12V supply is no longer required. The V
CC2 and
PWRGOOD pins can be connected to Vcc5v. This
eases the connection to “5V-only” MOSFET drivers,
such as the SC1405. The DRVs will swing to Vcc5v,
eliminating the need for +12V to +5V level shifting.
There is no Under-Voltage Lockout on V
CC2.
ERROR AMPLIFIER CONT.
Fig. 3: Transient response, Top trace, Current sense
8A/div @ 30A/usec. Bottom trace, V
OUT.
Fig. 4: Transient response, Top trace, Gate Drive
Bottom trace, Transient current 16A/div @ 30A/usec.
相关PDF资料 |
PDF描述 |
|---|---|
| SC1154CSW | PROGRAMMABLE SYNCHRONOUS DC/DC HYSTERETIC CONTROLLER FOR ADVANCED PROCESSORS |
| SC1158CS | PROGRAMMABLE SYNCHRONOUS DC/DC CONTROLLER FOR ADVANCED PROCESSORS |
| SC1403ITSTRT | 1 A DUAL SWITCHING CONTROLLER, 380 kHz SWITCHING FREQ-MAX, PDSO28 |
| SC15-11EWA | 7 SEG NUMERIC DISPLAY, HIGH EFFICIENCY RED, 38.1 mm |
| SC1531ACSTR | 200mA & 250mA SmartLDOs |
相关代理商/技术参数 |
参数描述 |
|---|---|
| SC1146CSW.TR | 制造商:SEMTECH 制造商全称:Semtech Corporation 功能描述:VRM9.0 PROGRAMMABLE, MULTI-PHASE, HIGH PERFORMANCE PWM CONTROLLER |
| SC11485 | 制造商:未知厂家 制造商全称:未知厂家 功能描述:HiCOLOR-16 Color Palette |
| SC11485CV | 制造商:未知厂家 制造商全称:未知厂家 功能描述:HiCOLOR-16 Color Palette |
| SC11485CV-110 | 制造商:未知厂家 制造商全称:未知厂家 功能描述:HiCOLOR-16 Color Palette |
| SC11485CV-66 | 制造商:未知厂家 制造商全称:未知厂家 功能描述:HiCOLOR-16 Color Palette |
发布紧急采购，3分钟左右您将得到回复。