General Description

The MAX7378 dual-speed silicon oscillator with reset, is

a replacement for ceramic resonators, crystals, crystal-

oscillator modules, and discrete reset circuits. The

MAX7378 provides the primary and secondary clock

source and reset function for microcontrollers in 3V,

3.3V, and 5V applications. The MAX7378 features a

factory-programmed

high-speed

oscillator,

a

32.768kHz oscillator, a clock selector input, and a

microprocessor (µP) power-on-reset (POR) supervisor.

The clock output can be switched at any time between

the high-speed clock and the 32.768kHz clock for low-

power operation. Switchover is synchronized internally

to provide glitch-free clock switching.

Unlike typical crystal and ceramic resonator oscillator

circuits, the MAX7378 is resistant to vibration and EMI.

The high-output-drive current and absence of high-

impedance nodes make the oscillator less susceptible

to dirty or humid operating conditions. With a wide

operating temperature range as standard, the

MAX7378 is a good choice for demanding home appli-

ance, industrial, and automotive environments.

Refer to the MAX7384 data sheet for frequencies

≥10MHz. The MAX7378 standard operating tempera-

ture range is -40

°C to +125°C. See the Applications

Information section for the extended operating temper-

ature range.

Applications

White Goods

Automotive

Consumer Products

Appliances and Controls

Handheld Products

Portable Equipment

Microcontroller (µC) Systems

Features

♦ 2.7V to 5.5V Operation

♦ Accurate High-Speed Oscillator: 600kHz to 10MHz

♦ Accurate Low-Speed 32kHz Oscillator

♦ Glitch-Free Switch Between High Speed and Low

Speed at Any Time

♦ Reset Output Holds the µC in Reset for 100µs

After Clock Startup

♦ ±10mA Clock-Output Drive Capability

♦ 2% Initial Accuracy

♦ ±50ppm/°C Temperature Coefficient

♦ 50% ±7% Output Duty Cycle

♦ 5ns Output Rise and Fall Time

♦ Low Jitter: 160ps (Peak-to-Peak) at 8MHz

♦ 2.4mA Fast-Mode Operating Current (8MHz)

♦ 11µA Slow-Mode Operating Current (32kHz)

♦ -40°C to +125°C Temperature Range

Silicon Oscillator with Low-Power

Frequency Switching and Reset Output

________________________________________________________________ Maxim Integrated Products

1

Ordering Information

19-3350; Rev 0; 7/04

For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at

1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

Pin Configuration appears at end of data sheet.

MAX7378

CLOCK

OSC1

OSC2

µC

RST

I/O PORT

SUPPLY VOLTAGE

ENABLE

RST/RST

SPEED

Typical Application Circuit

µMAX is a registered trademark of Maxim Integrated Products, Inc.

PART

TEMP RANGE

RESET

OUTPUT

PIN-

PACKAGE

MAX7378A _ _ _

-40

Active high

push-pull

8 µMAX

MAX7378B _ _ _

-40

Active low

push-pull

8 µMAX

MAX7378C _ _ _ -40

8 µMAX

Standard version is shown in bold. The first letter after the part

number designates the reset output option. Insert the letter cor-

responding to the desired reset threshold level from Table 1 in

the next position. Insert the two-letter code from Table 2 in the

remaining two positions for the desired frequency range. See

Table 3 for standard part numbers.