Philips 74HCT4059U, 74HCT4059N, 74HCT4059D, 74HC4059U, 74HC4059N3 Datasheet

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DATA SH EET
Product specification Supersedes data of September 1993 File under Integrated Circuits, IC06
1998 Jul 08
INTEGRATED CIRCUITS
74HC/HCT4059
For a complete data sheet, please also download:
The IC06 74HC/HCT/HCU/HCMOS Logic Family Specifications
The IC06 74HC/HCT/HCU/HCMOS Logic Package Information
The IC06 74HC/HCT/HCU/HCMOS Logic Package Outlines
1998 Jul 08 2
Philips Semiconductors Product specification
Programmable divide-by-n counter 74HC/HCT4059
FEATURES
Synchronous programmable divide-by-n counter
Presettable down counter
Fully static operation
Mode select control of initial decade counting function
(divide-by-10, 8, 5, 4 and 2)
Master preset initialization
Latchable output
Easily cascadable with other counters
Four operating modes:
timer divider-by-n divide-by-10 000 master preset
Output capability: standard
I
CC
category: MSI
GENERAL DESCRIPTION
The 74HC/HCT4059 are high-speed Si-gate CMOS devices and are pin compatible with the “4059” of the “4000B” series. They are specified in compliance with JEDEC standard no. 7A.
The 74HC/HCT4059 are divide-by-n counters which can be programmed to divide an input frequency by any number (n) from 3 to 15 999. There are four operating modes, timer, divide-by-n, divide-by-10 000 and master preset, which are defined by the mode select inputs (K
a
to Kc) and the latch enable input (LE) as shown in the Function table.
The complete counter consists of a first counting stage, an intermediate counting stage and a fifth counting stage. The first counter stage consists of four independent flip-flops. Depending on the divide-by-mode, at least one flip-flop is placed at the input of the intermediate stage (the remaining flip-flops are placed at the fifth stage with a place value of thousands). The intermediate stage consists of three cascaded decade counters, each containing four flip-flops.
All flip-flops can be preset to a desired state by means of the JAM inputs (J1 to J16), during which the clock input (CP) will cause all stages to count from n to zero. The zero-detect circuit will then cause all stages to return to the JAM count, during which an output pulse is generated. In the timer mode, after an output pulse is generated, the output pulse remains HIGH until the latch input (LE) goes LOW. The counter will advance, even if LE is HIGH and the output is latched in the HIGH state.
In the divide-by-n mode, a clock cycle wide pulse is generated with a frequency rate equal to the input frequency divided by n.
The function of the mode select and JAM inputs are illustrated in the following examples. In the divide-by-2 mode, only one flip-flop is needed in the first counting section. Therefore the last (5th) counting section has three flip-flops that can be preset to a maximum count of seven with a place value of thousands. This counting mode is selected when K
a
to Kc are set HIGH. In this case input J
1
is used to preset the first counting section and J2 to J4 are used to preset the last (5th) counting section.
If the divide-by-10 mode is desired for the first section, K
a
and Kb are set HIGH and Kc is set LOW. The JAM inputs J1 to J4 are used to preset the first counting section (there is no last counting section). The intermediate counting section consists of three cascaded BCD decade (divide-by-10) counters, presettable by means of the JAM inputs J5 to J16.
The preset of the counter to a desired divide-by-n is achieved as follows:
n = (MODE
(1)
) (1 000 x decade 5 preset
+ 100 x decade 4 preset + 10 x decade 3 preset + 1 x decade 2 preset) + decade 1 preset
To calculate preset values for any “n” count, divide the “n” count by the selected mode. The resultant is the corresponding preset value of the 5th to the 2nd decade with the remainder being equal to the 1st decade value; preset value = n/mode.
If n = 8 479, and the selected mode = 5, the preset value = 8 479/5 = 1 695 with a remainder of 4, thus the JAM inputs must be set as shown in Table 1.
To verify the results, use the given equation: n = 5 (1 000 × 1 + 100 × 6 + 10 × 9 + 1 × 5) + 4 n = 8 479. If n = 12 382 and the selected mode = 8, the preset
value = 12 382/8 = 1 547 with a remainder of 6, thus the JAM inputs must be set as shown in Table 2.
To verify: n = 8 (1 000 × 1 + 100 × 5 + 10 × 4 + 1 × 7) + 6 n = 12 382.
(1) MODE = first counting section divider
(10, 8, 5, 4 or 2).
1998 Jul 08 3
Philips Semiconductors Product specification
Programmable divide-by-n counter 74HC/HCT4059
If n = 8 479 and the selected mode = 10, the preset value = 8 479/10 with a remainder of 9, thus the JAM inputs must be set as shown in Table 3.
To verify: n = 10 (1 000 × 0 + 100 × 8 + 10 × 4 + 1 × 7) + 9 n = 8 479. The three decades of the intermediate counting section
can be preset to a binary 15 instead of a BCD 9. In this case the first cycle of a counter consists of 15 count pulses, the next cycles consisting of 10 counting pulses. Thus the place value of the three decades are still 1, 10 and 100. For example, in the divide-by-8 mode, the number from which the intermediate counting section begins to count-down can be preset to:
3rd decade: 1 500 2nd decade: 150 1st decade: 15
The last counting section can be preset to a maximum of 1, with a place value of 1 000. The first counting section can be preset to a maximum of 7. To calculate n:
n = 8 (1 000 × 1 + 100 × 15 + 10 × 15 + 1 × 15) + 7 n = 21 327. 21 327 is the maximum possible count in the divide-by-8
mode. The highest count of the various modes is shown in the Function table, in the column entitled “binary counter range”.
The mode select inputs permit, when used with decimal programming, a non-BCD least significant digit. For example, the channel spacing in a radio is 12.5 kHz, it may be convenient to program the counter in decimal steps of 100 kHz subdivided into 8 steps of 12.5 kHz controlled by the least significant digit. Also frequency synthesizer channel separations of 10, 12.5, 20, 25 and 50 parts can be chosen by the mode select inputs. This is called “Fractional extension”. A similar extension called “Half channel offset” can be obtained in modes 2, 4, 6 and 8, if the JAM inputs are switched between zero and 1, 2, 3 and 4 respectfully. This is illustrated in Fig.5.
This feature is used primarily in cases where radio channels are allocated according to the following formula:
Channel frequency = channel spacing x (N + 0.5) N is an integer.
Control inputs Kb and Kc can be used to initiate and lock the counter in the “master preset” mode. In this condition the flip-flops in the counter are preset in accordance with the JAM inputs and the counter remains in that mode as long as Kb and Kc both remain LOW. The counter begins to count down from the preset state when a counting mode other than the “master preset” mode is selected. Whenever the “master preset” mode is used, control signals Kb=Kc= LOW must be applied for at least 2 full clock pulses. After the “master preset” mode inputs have been changed to one of the counting modes, the next positive-going clock transition changes an internal flip-flop so that the count-down begins on the second positive-going clock transition. Thus, after a “master preset” mode, there is always one extra count before the output goes HIGH. Figure 6 illustrates the operation of the counter in the divide-by-8 mode starting from the preset state 3.
If the “master preset” mode is started two clock cycles or less before an output pulse, the output pulse will appear at the correct moment. When the output pulse appears and the “master preset” mode is not selected, the counter is preset according to the states of the JAM inputs.
When Ka, Kb, Kc and LE are LOW, the counter operates in the “preset inhibit” mode, during which the counter divides at a fixed rate of 10 000, independent of the state of the JAM inputs. However, the first cycle length after leaving the “master preset” mode is determined by the JAM inputs.
When Ka, Kb and Kc are LOW and input LE = HIGH, the counter operates in the normal divide-by-10 mode, however, without the latch operation at the output.
This device is particularly advantageous in digital frequency synthesizer circuits (VHF, UHF, FM, AM etc.) for communication systems, where programmable divide-by-”n” counters are an integral part of the synthesizer phase-locked-loop sub-system. The 74HC/HCT4059 can also be used to perform the synthesizer “fixed divide-by-n” counting function, as well as general purpose counting for instrumentation functions such as totalizers, production counters and “time out” timers.
Schmitt-trigger action at the clock input makes the circuit highly tolerant to slower clock rise and fall times.
1998 Jul 08 4
Philips Semiconductors Product specification
Programmable divide-by-n counter 74HC/HCT4059
QUICK REFERENCE DATA
GND = 0 V; T
amb
=25°C; tr=tf= 6 ns
Notes
1. C
PD
is used to determine the dynamic power dissipation (PD in µW):
PD=CPD× V
CC
2
× fi+∑(CV
CC
2
× fo) where: fi= input frequency in MHz fo= output frequency in MHz (CV
CC
2
× fo) = sum of outputs CL= output load capacitance in pF VCC= supply voltage in V
2. For HC the condition is VI= GND to V
CC
For HCT the condition is VI= GND to VCC− 1.5 V
ORDERING INFORMATION
SYMBOL PARAMETER CONDITIONS TYPICAL UNIT
HC HCT
t
PHL
/ t
PLH
propagation delay CP to Q CL= 15 pF; VCC=5 V1820ns
f
max
maximum clock frequency 40 40 MHz
C
I
input capacitance 3.5 3.5 pF
C
PD
power dissipation capacitance per package notes 1 and 2 30 32 pF
TYPE
NUMBER
PACKAGE
NAME DESCRIPTION VERSION
74HC4059N3; 74HCT4059N3
DIP24 plastic dual in-line package; 24 leads (300 mil) SOT222-1
74HC4059N; 74HCT4059N
DIP24 plastic dual in-line package; 24 leads (600 mil) SOT101-1
74HC4059D; 74HCT4059D
SO24 plastic small outline package; 24 leads; body width 7.5 mm SOT137-1
1998 Jul 08 5
Philips Semiconductors Product specification
Programmable divide-by-n counter 74HC/HCT4059
PIN DESCRIPTION
PIN NO. SYMBOL NAME AND FUNCTION
1 CP clock input (LOW-to-HIGH, edge-triggered) 2 LE latch enable (active HIGH) 3, 4, 5, 6, 22, 21, 20, 19, 18, 17, 16, 15, 10, 9, 8, 7 J
1
to J
16
programmable JAM inputs (BCD) 12 GND ground (0 V) 14, 13, 11 K
a
to Kcmode select inputs 23 Q divide-by-n output 24 V
CC
positive supply voltage
Fig.1 Pin configuration. Fig.2 Logic symbol. Fig.3 IEC logic symbol.
1998 Jul 08 6
Philips Semiconductors Product specification
Programmable divide-by-n counter 74HC/HCT4059
Fig.4 Functional block diagram.
APPLICATIONS
Frequency synthesizer, ideally suited for use with PC74HC/HCT4046A, PC74HC/HCT7046A and PC74HC/HCT9046A (PLLs)
Fixed or programmable frequency division
“Time out” timer
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