参数资料
型号: MAX1964TEEE+
厂商: Maxim Integrated Products
文件页数: 25/30页
文件大小: 0K
描述: IC POWER CTRLR/SEQUENCER 16QSOP
产品培训模块: Lead (SnPb) Finish for COTS
Obsolescence Mitigation Program
标准包装: 100
应用: 电源控制器,序列发生器
输入电压: 4.5 V ~ 28 V
电流 - 电源: 1.25mA
工作温度: -40°C ~ 85°C
安装类型: 表面贴装
封装/外壳: 16-SSOP(0.154",3.90mm 宽)
供应商设备封装: 16-QSOP
包装: 管件
Tracking/Sequencing Triple/Quintuple
Power-Supply Controllers
C DIODE = 0
shown  in  Figure  8,  a  series  RC  snubber  circuit  at  the
diode increases the damping factor, allowing the ring-
ing to settle quickly. Applications with multiple trans-
former windings require only one snubber circuit on the
highest output voltage.
The diode ’ s parasitic capacitance can be estimated
using the diode ’ s reverse voltage rating (V RRM ), current
capability (I O ), and recovery time (t RR ). A rough
approximation is:
I × t RR
V RRM
For the EC10QS10 Nihon diode used in Figure 8, the
capacitance is roughly 15pF. The output snubber only
needs to dampen the ringing, so the initial turn-on spike
that occurs during the blanking period is still present. A
100pF capacitor works well in most applications.
Larger capacitance values require more charge, there-
by increasing the power dissipation.
The snubber ’ s time constant (t SNUB ) must be smaller
than the 60ns blanking time. A typical RC time constant
of approximately 30ns was chosen for Figure 8:
2) Mount the MAX1964/MAX1965 adjacent to the
switching MOSFETs in order to keep IN-LX current-
sense lines, LX-GND current-limit sense lines, and
the driver lines (DL and DH) short and wide. The
current-sense amplifier inputs are connected
between IN and LX, so these pins must be connect-
ed as close as possible to the high-side MOSFET.
The current-limit comparator inputs are connected
between LX and GND, but accuracy is not as
important, so give priority to the high-side MOSFET
connections. The IN, LX, and GND connections to
the MOSFETs must be made using Kelvin sense
connections to guarantee current-sense and cur-
rent-limit accuracy.
3) Group the gate-drive components (BST diode and
capacitor, IN bypass capacitor) together near the
MAX1964/MAX1965.
4) All analog grounding must be done to a separate
solid copper ground plane, which connects to the
MAX1964/MAX1965 at the GND pin. This includes
the VL bypass capacitor, feedback resistors, com-
pensation components (R COMP , C COMP ), and
adjustable current-limit threshold resistors connect-
ed to ILIM.
R SNUB = =
t SNUB
C SNUB
30 ns
C SNUB
5) Ensure all feedback connections are short and
direct. Place the feedback resistors as close to the
MAX1964/MAX1965 as possible.
Minimum Load Requirements (Linear Regulators)
Under no-load conditions, leakage currents from the
pass transistors supply the output capacitor, even
when the transistor is off. Generally, this is not a prob-
lem since the feedback resistors ’ current drain the
excess charge. However, charge may build up on the
output capacitor over temperature, making V LDO rise
above its set point. Care must be taken to ensure that
the feedback resistors ’ current exceeds the pass tran-
sistor ’ s leakage current over the entire temperature
range.
Applications Information
PC Board Layout Guidelines
Careful PC board layout is critical to achieve low
switching losses and clean, stable operation. The
switching power stage requires particular attention.
Follow these guidelines for good PC board layout:
1) Place the power components first, with ground ter-
minals adjacent (NL source, C IN , C OUT ). If possi-
ble, make all these connections on the top layer
with wide, copper-filled areas. Keep these high-cur-
rent paths short, especially at ground terminals.
6) When trade-offs in trace lengths must be made, it ’ s
preferable to allow the inductor charging path to be
made longer than the discharge path. For example,
it is better to allow some extra distance between the
input capacitors and the high-side MOSFET than to
allow distance between the inductor and low-side
MOSFET.
7) Route high-speed switching nodes away from sen-
sitive analog areas (B_, FB_, COMP, ILIM).
Regulating High Voltage
The linear regulator controllers can be configured to
regulate high output voltages by adding a cascode
transistor to buffer the base-drive output. For example,
to generate an output voltage between 30V and 60V,
add a 2N5550 high-voltage NPN transistor as shown in
Figure 9A where VBIAS is a DC voltage between 3V
and 20V that can source at least 1mA. R DROP protects
the cascode transistor by decreasing the voltage
across the transistor when the pass transistor saturates.
Similarly, to regulate a negative output voltage between
-20V and -120V, add a 2N5401 high-voltage PNP tran-
sistor as shown in Figure 9B.
______________________________________________________________________________________
25
相关PDF资料
PDF描述
MAX1967EUB+T IC REG CTRLR BUCK PWM VM 10-UMAX
MAX1969EUI+T IC DRVR POWER 28-TSSOP
MAX1971EEE+T IC REG BUCK SYNC 0.75A DL 16QSOP
MAX1973EUB+T IC REG BUCK SYNC ADJ 1A 10UMAX
MAX1977EEI+ IC CNTRLR PS QUAD HI EFF 28QSOP
相关代理商/技术参数
参数描述
MAX1964TEEE+ 功能描述:电流和电力监控器、调节器 Track/Seq Trpl/Wuint Power-Supply Ctlr RoHS:否 制造商:STMicroelectronics 产品:Current Regulators 电源电压-最大:48 V 电源电压-最小:5.5 V 工作温度范围:- 40 C to + 150 C 安装风格:SMD/SMT 封装 / 箱体:HPSO-8 封装:Reel
MAX1964TEEE+T 功能描述:电流和电力监控器、调节器 Track/Seq Trpl/Wuint Power-Supply Ctlr RoHS:否 制造商:STMicroelectronics 产品:Current Regulators 电源电压-最大:48 V 电源电压-最小:5.5 V 工作温度范围:- 40 C to + 150 C 安装风格:SMD/SMT 封装 / 箱体:HPSO-8 封装:Reel
MAX1964TEEE-T 功能描述:电流和电力监控器、调节器 RoHS:否 制造商:STMicroelectronics 产品:Current Regulators 电源电压-最大:48 V 电源电压-最小:5.5 V 工作温度范围:- 40 C to + 150 C 安装风格:SMD/SMT 封装 / 箱体:HPSO-8 封装:Reel
MAX1965TEEP 功能描述:电流和电力监控器、调节器 RoHS:否 制造商:STMicroelectronics 产品:Current Regulators 电源电压-最大:48 V 电源电压-最小:5.5 V 工作温度范围:- 40 C to + 150 C 安装风格:SMD/SMT 封装 / 箱体:HPSO-8 封装:Reel
MAX1965TEEP-T 功能描述:电流和电力监控器、调节器 RoHS:否 制造商:STMicroelectronics 产品:Current Regulators 电源电压-最大:48 V 电源电压-最小:5.5 V 工作温度范围:- 40 C to + 150 C 安装风格:SMD/SMT 封装 / 箱体:HPSO-8 封装:Reel