TC648 Ver la hoja de datos (PDF) - Microchip Technology

Número de pieza

componentes Descripción

Fabricante

TC648

Fan Speed Controller with Auto-Shutdown and Over-Temperature Alert

Microchip Technology 

TC648

5.0 TYPICAL APPLICATIONS

Designing with the TC648 involves the following:

(1) The temperature sensor network must be

configured to deliver 1.25V to 2.65V on VIN for 0%

to 100% of the temperature range to be regulated.

(2) The auto-shutdown temperature must be set with

a voltage divider on VAS (if used).

(3) The output drive transistor and base resistor must

be selected.

(4) If reset/shutdown capability is desired, the drive

requirements of the external signal or circuit must

be considered.

The TC642 demonstration and prototyping board

(TC642DEMO) and the TC642 Evaluation Kit

(TC642EV) provide working examples of TC648 cir-

cuits and prototyping aids. The TC642DEMO is a

printed circuit board optimized for small size and ease

of inclusion into system prototypes. The TC642EV is a

larger board intended for benchtop development and

+5V*

analysis. At the very least, anyone contemplating a

design using the TC648 should consult the documen-

tation for both the TC642EV (DS21403) and

TC642DEMO (DS21401). Figure 5-1 shows the base

schematic for the TC642DEMO.

An Excel-based spreadsheet is also available for

designing the thermistor network for the TC64X fan

controllers. This file (TC64X Therm) is available for

downloading from the Microchip website at

www.microchip.com.

Shutdown**

R1

NTC

CB

1 µF

R2

+5V

R3

R4

VIN

CB

0.01 µF

VDD

TC648

VAS

CB

0.01 µF

CF

CF

1 µF

GND

OTF

VOUT

NC

+12V

Over-

Temperature

Interrupt

RBASE

Fan

Q1

NOTES: *See cautions regarding latch-up considerations in Section 5.0, "Typical Applications".

**Optional. See Section 5.0, "Typical Applications", for details.

FIGURE 5-1:

Typical Application Circuit.

 2002 Microchip Technology Inc.

DS21448C-page 9

Share Link: