HT32F1251_12 Datasheet, PDF (25/35 Pages) Holtek Semiconductor Inc – Holtek 32-bit Microcontroller with ARM® Cortex™-M3 Core

32-bit ARM Cortex™-M3 MCU
HT32F1251/51B/52/53
Internal Clock Characteristics
Table 10. High Speed Internal Clock (HSI) Characteristics
Symbol
Parameter
Conditions
fHSI
High Speed Internal Oscillator VDD33 = 3.3V,
Frequency (HSI )
TA = -40°C ~ +85°C
ACCHSI
HSI Oscillator Frequency
accuracy
Factory-trimmed,
VDD33 = 3.3V, TA = 25°C
DHSI
HSI Oscillator Duty cycle
VDD33 = 3.3V, fHSI = 8MHz
IDDHSI
HSI Oscillator Operating
Current
VDD33 = 3.3V, fHSI = 8MHz
tSUHSI
HSI Oscillator Startup time
VDD33 = 3.3V, fHSI = 8MHz,
HSIRCBL = 0 (HSI Ready
Counter Bits Length 7 Bits )
NOTE: HSIRCBL field is in PWRCU HSIRCR register
TA = 25°C, unless otherwise specified.
Min Typ Max Unit
TBD
8
TBD MHz
-1
—
+1
%
35
—
65
%
—
0.92
—
mA
—
17
—
μs
Table 11. Low Speed Internal Clock (LSI) Characteristics
Symbol
Parameter
Conditions
fLSI
Low Speed Internal Oscillator VDD33 = VBAT = 3.3V,
Frequency(LSI)
TA = -40°C ~ +85°C
IDDLSI
LSI Oscillator Operating
Current
VDD33 = VBAT = 3.3V,
TA = 25°C
tSULSI
LSI Oscillator Startup time
VDD33 = VBAT = 3.3V,
TA = 25°C
TA = 25°C, unless otherwise specified.
Min Typ Max Unit
25
32
43
kHz
—
1.0
2
μA
—
35
—
ms
Rev. 1.10
25 of 35
April 13, 2012