M25P16 Datasheet, PDF (34/55 Pages) STMicroelectronics – 16 Mbit, Low Voltage, Serial Flash Memory With 50 MHz SPI Bus Interface

Instructions
M25P16
Figure 19. Release from Deep Power-down and Read Electronic Signature (RES) instruction
sequence and data-out sequence
S
0 1 2 3 4 5 6 7 8 9 10 28 29 30 31 32 33 34 35 36 37 38
C
Instruction
3 Dummy bytes
t_RES2
D
23 22 21 3 2 1 0
MSB
High Impedance
Q
Electronic Signature Out
76543210
MSB
Deep Power-down mode
1. The value of the 8-bit electronic signature, for the M25P16, is 14h.
Figure 20. Release from Deep Power-down (RES) instruction sequence
Standby mode
AI04047C
S
01234567
t_RES1
C
Instruction
D
High Impedance
Q
Deep Power-down mode Standby mode
AI04078B
Driving Chip Select (S) High after the 8-bit instruction byte has been received by the device, but before
the whole of the 8-bit electronic signature has been transmitted for the first time (as shown in Figure 20),
still ensures that the device is put into Standby Power mode. If the device was not previously in the Deep
Power-down mode, the transition to the Standby Power mode is immediate. If the device was previously
in the Deep Power-down mode, though, the transition to the Standby Power mode is delayed by t_RES1,
and Chip Select (S) must remain High for at least t_RES1(max). Once in the Standby Power mode, the
device waits to be selected, so that it can receive, decode and execute instructions.
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