HEF4521B(2009) 查看數據表（PDF） - NXP Semiconductors.
零件编号
产品描述 (功能)
生产厂家
HEF4521B Datasheet PDF : 17 Pages
| |||
NXP Semiconductors
RTC
C
VDD
RS
VDD
VDD1
A1
Y1
Y2
Q18
A2
HEF4521B
MR
VSS
Q24
VSS1
001aae714
Fig 8.
f ≈ -2--.--3----×-----R--1--T---C-----×-----C-- ; RS ≥ 2RTC , where:
f is in Hz, R is in Ω, and C is in F.
RS + RTC < V-----I--L-I--(L--m-I--a---x--) , where:
VIL(max) = maximum input voltage LOW; and
ILI = input leakage current.
RC oscillator circuit
HEF4521B
24-stage frequency divider and oscillator
102
fosc
(1)
(kHz)
10
(2)
1
001aae715
10−1
1
10
10−1
1
102 RTC (kΩ) 103
10 C (nF) 102
VDD = 10 V; The test circuit is shown in Figure 8.
(1) RTC; C = 1 nF; RS ≈ 2 RTC.
(2) C; RTC = 56 kΩ; RS = 120 kΩ.
Fig 9. Oscillator frequency as a function of
RTC and C
HEF4521B_5
Product data sheet
Rev. 05 — 5 November 2009
© NXP B.V. 2009. All rights reserved.
11 of 17
Share Link: 