3-76

Detailed Description

The ICL7667 is a dual high-power CMOS inverter whose

inputs respond to TTL levels while the outputs can swing as

high as 15V. Its high output current enables it to rapidly

charge and discharge the gate capacitance of power

MOSFETs, minimizing the switching losses in switchmode

power supplies. Since the output stage is CMOS, the output

any external parts or extra power supplies as required by the

15V, the propagation delays and specifications are almost

In addition to power MOS drivers, the ICL7667 is well suited

for other applications such as bus, control signal, and clock

drivers on large memory of microprocessor boards, where

the load capacitance is large and low propagation delays are

required. Other potential applications include peripheral

power drivers and charge-pump voltage inverters.

Input Stage

The input stage is a large N-Channel FET with a P-channel

constant-current source. This circuit has a threshold of about

1.5V, relatively independent of the VCC voltage. This means

that the inputs will be directly compatible with TTL over the

less than 1

µA of current over the entire input voltage range

current of the ICL7667 is affected by the input voltage, going

to nearly zero when the inputs are at the 0 logic level and

rising to 7mA maximum when both inputs are at the 1 logic

level. A small amount of hysteresis, about 50mV to 100mV at

the input, is generated by positive feedback around the

second stage.

Output Stage

The ICL7667 output is a high-power CMOS inverter,

output impedance of the inverter is typically 7

Ω. The high

FREQUENCY (Hz)

100

10

1

100

µA

10K

100K

1M

10M

100

10

1

100mA

10k

100k

1M

10M

FREQUENCY (Hz)

50

40

30

20

10

0

510

15

50

40

30

20

10

0

510

15

ICL7667