HV7100 Datasheet, PDF (1/7 Pages) Supertex, Inc – 24V/48V Fan Driver/Controller With High-Side Drive

Supertex inc.
HV7100
Initial Release
24V/48V Fan Driver/Controller With High-Side Drive
Features
High-side drive allows use of tachs
Direct interface to host controller
Noise-immune linear speed control
4-bit digital speed control
Operates from single +24V/+48V supply
Programmable PWM frequency
Undervoltage lockout
Applications
24V/48V chassis cooling tray
Servers
SAN equipment
Cellular and fix wireless systems
24V/48V PBX system
Base stations
Typical Application Circuit
V_PP
General Description
The HV7100 is an integrated PWM speed controller for driving
24V and 48V DC Fans. The features and benefits provided
by the HV7100 make driving fans simple and low cost. The
HV7100 drives a high side external P-channel FET, allowing
the use of fans having a ground-based tachometer signal. It
has a wide input voltage range of +16V to +90V, ideal for +24V
or +48V systems. No low voltage supply is needed.
A 4-bit digital control input provides direct interfacing with a
microcontroller or system processor to control the fan speed.
It can also be used as a stand-alone fan controller, via a
thermistor connection to the Linear Control pin.
The HV7100 has a wide PWM frequency range. When driving
fans directly with a PWM supply voltage, frequency may be set
low, around 50Hz - 120Hz. When used to drive fans requiring
a DC supply, an LC filter may be employed. In this case, PWM
frequency may be as high as 100kHz, reducing component
sizes in the filter.
The HV7100 is an ideal device to incorporate in fan trays
and fan control modules, as it reduces circuit complexity
and minimizes parts count and overall cost for thermal
management.
speed control
Host
Controller
enable
V_PP1 V_PP2
V_GATE
DIN0 - DIN3
HV7100
EN
LIN
C_T
R_T
V_DD
OUT
GND
Optional LC filter for
providing a DC fan drive.
tach signals
· · · · ^{Supertex inc. 1235 Bordeaux Drive, Sunnyvale, CA 94089 Tel: [phone] FAX: [phone] www.supertex.com}
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