TC1427CPA Microchip Technology Inc., TC1427CPA Datasheet - Page 6

• Manufacturer Part Number: TC1427CPA
• Description: 1.2A DUAL MOSFET DRVR
• Manufacturer: Microchip Technology Inc.

Specifications of TC1427CPA

• Lead Free Status / Rohs Status: RoHS Compliant part Electrostatic Device

TC1426/TC1427/TC1428
3.0
3.1
Large currents are required to charge and discharge
capacitive loads quickly. For example, charging a 1000
pF load to 16V in 25 nsec requires a 0.8A current from
the device's power supply.
To ensure low supply impedance over a wide frequency
range, a parallel capacitor combination is recom-
mended for supply bypassing. Low-inductance ceramic
MLC capacitors with short lead lengths (<0.5-in.)
should be used. A 1.0 μF film capacitor in parallel with
one or two 0.1 μF ceramic MLC capacitors normally
provides adequate bypassing.
3.2
The TC1426 and TC1428 contain inverting drivers.
Individual ground returns for the input and output
circuits or a ground plane should be used. This will
reduce negative feedback that causes degradation in
switching speed characteristics.
FIGURE 3-1:
Time
DS21393C-page 6
Test Circuit
Output
Input
V
+5V
0V
DD
0V
Input
APPLICATIONS INFORMATION
SUPPLY BYPASSING
GROUNDING
10%
90%
t
D1
(1/2 TC1428)
10%
V
TC1426
DD
Inverting Driver Switching
t
1
2
F
= 16V
1 μF
WIMA
MKS-2
t
D2
C
L
90%
0.1 μF MLC
Output
= 1000 pF
t
R
10%
90%
3.3
The input voltage level changes the no-load or
quiescent supply current. The N-channel MOSFET
input stage transistor drives a 2.5 mA current source
load. With a logic ‘1’ input, the maximum quiescent
supply current is 9 mA. Logic ‘0’ input level signals
reduce quiescent current to 500 μA maximum. Unused
driver inputs must be connected to V
Minimum power dissipation occurs for logic ‘0’ inputs
for the TC1426/TC1427/TC1428.
The drivers are designed with 100 mV of hysteresis.
This provides clean transitions and minimizes output
stage current spiking when changing states. Input
voltage thresholds are approximately 1.5V, making a
logic ‘1’ input any voltage greater than 1.5V up to V
Input current is less than 1 μA over this range.
The TC1426/TC1427/TC1428 may be directly driven
by the TL494, SG1526/27, TC38C42, TC170 and
similar switch-mode power supply integrated circuits.
FIGURE 3-2:
Switching Time
Test Circuit
Output
Input
V
+5V
DD
0V
0V
INPUT STAGE
Input
10%
t
D1
(1/2 TC1428)
90%
V
Noninverting Driver
TC1427
DD
© 2006 Microchip Technology Inc.
10%
1
2
= 16V
t
R
1 μF
WIMA
MKS-2
t
90%
D2
C
L
0.1 μF MLC
DD
Output
= 1000 pF
10%
or GND.
90%
DD
t
F
.