1. General description
The HEF4541B is a programmable timer which consists of a 16-stage binary counter, an
integrated oscillator to be used with external timing components, an automatic power-on
reset and output control logic. The frequency of the oscillator is determined by the external
components R
TC
and C
TC
within the frequency range 1 Hz to 100 kHz. This oscillator may
be replaced by an external clock signal at input RS, the timer advances on the
positive-going transition of RS. A LOW on the auto reset input (AR) and a LOW on the
master reset input (MR) enables the internal power-on reset. A HIGH level at input MR
resets the counter independent on all other inputs. Resetting disables the oscillator to
provide no active power dissipation.
A HIGH at input AR turns off the power-on reset to provide a low quiescent power
dissipation of the timer. The 16-stage counter divides the oscillator frequency by 2
8
, 2
10
,
2
13
or 2
16
depending on the state of the address inputs (A0, A1). The divided oscillator
frequency is available at output O. The phase input (PH) features a complementary output
signal. When the mode select input (MODE) is LOW the timer is a single transition timer
and when HIGH the timer is a 2
n
frequency divider.
It operates over a recommended V
DD
power supply range of 3 V to 15 V referenced to V
SS
(usually ground). Unused inputs must be connected to V
DD
, V
SS
, or another input.
2. Features and benefits
Fully static operation
5 V, 10 V, and 15 V parametric ratings
Standardized symmetrical output characteristics
Operates across the automotive temperature range 40 C to +85 C
Complies with JEDEC standard JESD 13-B
3. Ordering information
HEF4541B
Programmable timer
Rev. 5 — 15 December 2015 Product data sheet
Table 1. Ordering information
All types operate from
40
C to +85
C.
Type number Package
Name Description Version
HEF4541BT SO14 plastic small outline package; 14 leads; body width 3.9 mm SOT108-1
