NTE4541B and NTE4541BT
Integrated Circuit
CMOS, Programmable Timer
Description:
The NTE4541B (14−Lead DIP) and NTE4541BT (SOIC−14) programmable timers consist of a
10−stage binary counter, an integrated oscillator for use with an external capacitor and two resistors,
an automatic power−on reset circuit, and output control logic.
Timing is initialized by turning on power, whereupon the power−on reset is enabled and initializes the
counter, within the specified VDD range. With the power already on, an external reset pulse can be
applied. Upon release of the initial reset command, the oscillator will oscillate with a frequency de-
termined by the external RC network. For 16−stage counter divides the oscillator frequency (fOSC
)
with the nth stage frequency being fOSC/2n.
Features:
D Available Outputs 28, 210, 213, or 216
D Increments on Positive Edge Clock Transitions
D Low Symmetrical Output Resistance (Typically 10Ω at 15Vdc)
D Built−In Low Power RC Oscillatior
( 2% Accuracy over Temperature Range and 10% Supply and
3% over Processing at < 10kHz)
D Oscillator Frequency Range ꢀ DC to 100kHz
D Oscillator may be Bypassed if External Clock is Available (Apply External Clock to Pin3)
D Automatic Reset Initializes All Counters when Power Turn On
(Limits − VDD from 8.5Vdc to 18Vdc when Enabled)
D External Master Reset Totally Independent of Automatic Reset Operation
D Operates as 2n Frequency Divider or Single Transition Timer
D Q/Q Select Provides Output Logic Level Flexibility
D Reset (Auto or Master) Disables Oscillator during Resetting to Provide No Active Power Dissipation
D Clock Conditioning Circuit Permits Operation with Very Slow Clock Rise and Fall Times
D Supply Voltage Range = 3Vdc to 18Vdc
Absolute Maximum Ratings: (Voltages Referenced to VSS)
DC Supply Voltage, VDD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.5 to +18.0V
Input Voltage (All Inputs), Vin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.5 to VDD + 0.5V
DC Current Drain (Per Pin), I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45mA
Operating Temperature Range, TA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −55 to +125°C
Storage Temperature Range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −65 to +150°C