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UM3304 Datasheet, PDF (10/15 Pages) ShenZhen XinDeYi Electronics Co., Ltd. – N-Ch and P-Ch 30V Fast Switching MOSFETs
UM3304/UM3304Q/UM3304QT
Input Driver Requirements
Typical IIN vs VIN characteristics of the UM3304/UM3304Q/UM3304QT are shown in Figure 2.
For proper operation, the device driving the data I/Os of the UM3304/UM3304Q/UM3304QT
must have drive strength of at least ±2 mA.
A: VT is the input threshold voltage of the UM3304/UM3304Q/UM3304QT (typical VCCI/2)
B: VD is the supply voltage of the external driver.
Power Up
Figure 2 Typical IIN vs VIN Curve
During operation, ensure that VCCA≤VCCB at all times. During power-up sequencing, VCCA≥ VCCB
does not damage the device, so any power supply can be ramped up first. The
UM3304/UM3304Q/UM3304QT has circuitry that disables all output ports when either VCC is
switched off (VCCA/B = 0 V).
Enable and Disable
The UM3304/UM3304Q/UM3304QT has an OE input that is used to disable the device by setting
OE = low, which places all I/Os in the high-impedance (Hi-Z) state. The disable time (tdis)
indicates the delay between when OE goes low and when the outputs acutally get disabled (Hi-Z).
The enable time (ten) indicates the amount of time the user must allow for the one-shot circuitry
to become operational after OE is taken high.
Pullup or Pulldown Resistors on I/O Lines
The UM3304/UM3304Q/UM3304QT is designed to drive capacitive loads of up to 50pF. The
output drivers of the UM3304/UM3304Q/UM3304QT have low dc drive strength. External pullup
or pulldown resistors need higher than 50 kΩ.
For the same reason, the UM3304/UM3304Q/UM3304QT should not be used in open-drain
system, such as I2C or 1-wire system.
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http://www.union-ic.com Rev.11 Sep.2013
10/15